Flexibility: A Concise Guide: To Conditioning, Performance Enhancement, Injury Prevention, and Rehabilitation (Musculoskeletal Medicine)

FLEXIBILITY:

A

CONCISE GUIDE

Musculoskeletal Medicine Flexibility: A Concise Guide to Conditioning, Performance Enhancement, Injury Prevention, and Rehabilitation By Laurence E. Holt, Thomas W. Pelham, and Jason Holt

Essential Sports Medicine Edited by Grant Cooper and Joseph E. Herrera

Essential Physical Medicine and Rehabilitation Edited by Grant Cooper

Pocket Guide to Musculoskeletal Diagnosis Edited by Grant Cooper

Series Editors Grant Cooper Department of Physical Medicine and Rehabilitation, New York Presbyterian Hospital, The University Hospital of Columbia and Cornell, New York, NY, USA Joseph E. Herrera Director of Sports Medicine, Interventional Spine and Sports Medicine Division, Department of Rehabilitation Medicine, Mount Sinai School of Medicine, New York, NY, USA

FLEXIBILITY: A CONCISE GUIDE To Conditioning, Performance Enhancement, Injury Prevention, and Rehabilitation Laurence E. Holt, PhD Professor (R), School of Health and Human Performance, Faculty of Health Professions, Dalhousie University, Halifax, NS, Canada

Thomas W. Pelham, MS, PT, CSCS Physical Therapist, Waverley, NS, Canada

Jason Holt, PhD Assistant Professor, School of Recreation Management and Kinesiology Acadia University, Wolfville, NS, Canada

© 2008 Humana Press Inc., a part of Springer Science+Business Media, LLC 999 Riverview Drive, Suite 208 Totowa, New Jersey 07512

humanapress.com All rights reserved. No part of this book may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, microfilming, recording, or otherwise without written permission from the Publisher. The content and opinions expressed in this book are the sole work of the authors and editors, who have warranted due diligence in the creation and issuance of their work. The publisher, editors, and authors are not responsible for errors or omissions or for any consequences arising form the information or opinions presented in this book and make no warranty, express or implied, with respect to its contents. This publication is printed on acid-free paper. 8 ANSI Z39.48-1984 (American Standards Institute)Permanence of Paper for Printed Library Materials. For additional copies, pricing for bulk purchases, and/or information about other Humana titles, contact Humana at the above address or at any of the following numbers: Tel.: 973256-1699; Fax: 973-256-8341; or visit our Website: www.humanapress.com

Photocopy Authorization Policy: Authorization to photocopy items for internal or personal use, or the internal or personal use of specific clients, is granted by Humana Press Inc., provided that the base fee of US $30.00 per copy is paid directly to the Copyright Clearance Center at 222 Rosewood Drive, Danvers, MA 01923. For those organizations that have been granted a photocopy license form the CCC, a separate system of payment has been arranged and is acceptable to Humana Press Inc. The fee code for users of the Transactional Reporting Service is: [978-1-60327-104-2/08 $30.00]. 10 9 8 7 6 5 4 3 2 1 e-ISBN: 978-1-60327-105-9 Library of Congress Control Number: 2007930603

To all the athletes, dancers, and everyday folk whose exercise experiences were less than optimal, and who suffered through debilitating injuries in their quest for excellence.

Recommendation

The first principle of exercise prescription is: Do no harm. Our intention is to provide information and exercise protocols that will enhance conditioning, improve performance, reduce injury, facilitate rehabilitation, and add to our body of knowledge in the movement sciences. Individuals should consult a health care professional before beginning any exercise program.

VII

Preface

In 1964, at the beginning of my PhD studies at Southern Illinois University, I was first introduced to the theory and practice of proprioceptive neuromuscular facilitation (PNF). One specific application, reversal of antagonists, particularly intrigued me, and served as the focus of not only my dissertation, but also numerous research projects, presentations, and publications over the ensuing years, including the monograph Scientific Stretching for Sport (1973). This was the first publication to present a simplified. planar version of reversal of antagonists for enhancing flexibility. Although I was repeatedly encouraged by friends and colleagues to write a more extensive text, I knew that more laboratory research, methodological fine-tuning, clinical information, and significant changes to the conceptual foundations, were needed before a truly meaningful book could be written. Throughout my 36 years at Dalhousie University. I have been fortunate to have had a number of excellent graduate students whose theses contributed much of this needed material. Their work has been published in numerous academic journals and is referenced throughout this text. However, it was not until I was joined in this project by my coauthors that this book became fully realizable. Tom Pelham is one of Canada's leading physical therapy researchers. His productivity has been outstanding, with 60 publications (and senior authorship on 40 of them) over the past 15 years. Impressively, he has achieved all of this without the advantage of an academic post, having spent these years as a clinical physical therapist. In addition to much of the laboratory research. Tom contributed to the literature searches, and is responsible for the clinical applications in this book. Jason Holt has been involved in this research since his undergraduate years at Acadia University. Concepts from his ongoing, extensive literature reviews have served as the basis for our new definition of flexibility. helped identify significant errors in many of the research articles we have addressed. and shaped our critical assessment of theories advanced and positions held by those considered leaders in the field. In addition to his ix

x

Preface

semantic/conceptual contributions, his original writing and editing have made this book much more cohesive and concise than it would have been otherwise. It is owing to his efforts that the book reads as if from a single voice. For this book to be the definitive guide we envision, we think it necessary not only to cover the topic, but to provide a fresh perspective, one that challenges current thinking and professional practice, from the conceptual foundations of research to the practical applications of various techniques in a number of domains. Our objective is to encapsulate in one volume all of the pertinent information on this topic and present it in a clear, concise, and accessible manner. Unlike other books on flexibility, this one is based on 40 years of research by the senior author, including 15 years of collaboration with the coauthors, years of clinical and practical experimentation, extensive feedback from diverse professionals, and a thorough and critical examination of the works in the field. From the theoretical foundations of tissue adaptation, including our "fascia hypothesis," to the full gamut of stretching protocols, this book will establish a new understanding of this most important physiological property. The book is divided into two sections, practical and theoretical. Readers may choose those chapters that suit their particular interests and needs. Coaches, athletes, personal trainers, and others interested in practical applications might choose to focus on Chapters 1 to 6, whereas physicians, physical therapists, athletic trainers, osteopaths, chiropractors, as well as other medical and paramedical professionals, might focus on Chapters 7 to 10. Clinical health researchers, physical educators, kinesiologists, sport and exercise scientists, and others who devote a good deal of their professional lives to this topic, may instead prefer a close reading of the entire book. Laurence E. Holt

Acknowledgments

We acknowledge the clinical and academic works of H. Kabat, physician, and physical therapists M. Knott, D.W. Voss, and T. Okita. Our appreciation to: Jody Myers,* Craig Slaunwhite, Kalessy Lasserre, Allison Vigeant, Michael Gorman, Bruce Johnson,t and Colin Duerdent for serving as demonstrators of the exercises; Shirley Wheaton for her deciphering, organizational, and typing skills; Dave Grimshire for helping with the photographic sessions; Monique Guilderson for the medical illustrations; and Jim Hoyle and Robert Stalker for editing and conceptual feedback.

*lody is an experienced and sought-after yoga instructor in the Halifax area, and has published her own teaching manual. She can be reached at . tThose who have a copy of Scientific Stretching for Sport (1973) may recognize both Bruce and Colin, who served as demonstrators in the original monograph. Xl

Contents

Recommendation Preface Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

VII

Introduction Previous Attempts to Define Flexibility ............... One-Word Definitions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Range-of-Motion Definitions Ability Definitions General Problems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A New Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Components, Demonstrations, and Measures Summary...............................................

1 1 2 2 2 3 3 4 6

IX Xl

Part I Practical Considerations Chapter I-Stretching Techniques and Exercise Prescriptions . . . . yoga................................................... Slow/Static Stretching. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Dynamic Stretching Comparison of Slow/Static, Dynamic, and PNF Techniques. . . . PNF Variations and Effects Reversal of Antagonists (3S) Exercise Prescription for 3S Summary...............................................

11 11 12 12 15 15 16 18 21

Chapter 2-Stretching the Major Muscle Groups of the Lower Limb Exercise I-Hip Extensors (3S Method) Exercise I-Hip Extensors (Alternative Methods) . . . . . . . . . . . .

23 24 25 Xlii

xiv

Contents Exercise 2-Hip Adductors (3S Method) . . . . . . . . . . . . . . . . . . . . Exercise 2-Hip Adductors (Alternative Methods) .. Exercise 3-Hip Flexors (3S Method) . . . . . . . . . . . . . . . . . . . . . . . Exercise 3-Hip Flexors (Alternative Methods) . . . . . . . . . . . . . . Exercise 4-Hip Inward (Medial) Rotators (3S Method) Exercise 4-Hip Inward (Medial) Rotators (Alternative Methods) Exercise 5-Hip Outward (Lateral) Rotators (3S Method) Exercise 5-Hip Outward (Lateral) Rotators (Alternative Methods) Exercise 6-Plantar Flexors (3S Method) Exercise 6-Plantar Flexors (Alternative Methods) . . . . . . . . . . .

Chapter 3-Stretching the Major Muscle Groups of the Upper Limb Exercise 7-Shoulder Extensors (3S Method) . . . . . . . . . . . . . . . . Exercise 7-Shoulder Extensors (Alternative Methods) .. . . . . . Exercise 8-Shoulder Horizontal Adductors (3S Method) ..... Exercise 8-Shoulder Horizontal Adductors (Alternative Methods) Exercise 9-Shoulder Inward (Medial) Rotators (3S Method) . . . Exercise 9-Shoulder Inward Rotators (Alternative Methods). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Exercise lO-Wrist Flexors (3S Method) Exercise lo-Wrist Flexors (Alternative Methods)

26 27 28 29 30 31 32 33 34 35

37 38 39 40 41 42 43 44 45

Chapter 4-Stretching the Major Muscle Groups of the Trunk and Neck. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Exercise II-Trunk Extensors (3S Method) Exercise ll-Trunk Extensors (Alternative Methods) Exercise 12-Trunk Lateral Flexors (3S Method) Exercise 12-Trunk Lateral Flexors (Alternative Methods) . . . . Exercise 13-Trunk Rotators (3S Method) Exercise 13-Trunk Rotators (Alternative Methods) Exercise 14-Neck Quadrant (Range-of-Motion Method)

47 48 49 50 51 52 53 54

Chapter 5-Advanced 3S Stretching Exercises for Figure Skaters, Gymnasts, Divers, and Dancers Exercise 15-Hip Adductors (Advanced) Exercise 16-Hip Extensors (in Flexion) Exercise 17-Split (Adductor-Extensor) Exercise 18-Split (Adductor)

55 56 57 58 59

Chapter 6-Sports, Fitness, and Dance Applications

61

Contents

xv

Part II Theoretical Considerations Chapter 7-Flexibility and Exercise. . . . . . . . . . . . . . . . . . . . . . . . . . . Factors That Affect Flexibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ways to Improve Flexibility. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Different Stretching Methods. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . When and How to Stretch When Not to Stretch Training Principles Summary...............................................

78 79 79

Chapter 8-Myths About Stretching Review of Reviews . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Myth 1: Stretching Causes Injury. . . . . . . . . . . . . . . . . . . . . . . . . . . Myth 2: Stretching Leads to Damage and Dysfunction Myth 3: Stretching Does Not Prevent Injuries. . . . . . . . . . . . . . . . Myth 4: Stretching Does Not Improve Performance Myth 5: Stretching Has No Therapeutic Value Myth 6: All Forms of Stretching Have Similar Effects. . . . . . . . . Summary...............................................

83 83 84 86 88 90 92 93 94

Chapter 9-Clinical Concepts and Applications Flexibility and Range of Motion Functional Flexibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Correcting Muscle Imbalances ... . . . . . . . . . . . . . . . . . . . . . . . . . . Choosing a Stretching Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Flexibility and Traditional Chinese Medicine Clinical Techniques and Modalities. . . . . . . . . . . . . . . . . . . . . . . . . Diabetes Mellitus Contraindications and Precautions Final Remarks. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

97 97 98 99 100 100 104 109 L10 L10

Chapter to-The Mechanisms of Flexibility Enhancement. . . . . . . The Muscle/Fascia/Tendon Complex How 3S Works A Biomechanical Explanation Theoretical Interpretations of Neural and Tissue Adaptations Our View of Adaptation Mechanisms: The Fascia Hypothesis

113 114 115 119

Conclusion Appendix A: Glossary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Appendix B: Applied Anatomy of 3S Stretches Appendix C: Research on The FlexAbility Machines. . . . . . . . . .

69 69 76 77 77

120 121 127

128 131 133

xvi

Contents

Appendix D: Machine and Solo 3S Exercises. . . . . . . . . . . . . . . . . Appendix E: Recommended Exercises for Specific Activities. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

135 138

Bibliography. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Index. . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

141 155

I Practical Considerations

Introduction

Flexibility is one of the physiological parameters involved in almost all forms of human movement. It is also a necessary component of general health, fitness, and sport-specific conditioning. Flexibility exercises have been advocated as a means of preventing and treating injuries, as well as a way to improve performance. We all have some idea of what flexibility is, yet there is no satisfactory definition of it in the literature. This has lead to misinterpretations of the term, misapplications of the concept, and consequent difficulties not only in researching this parameter, but also in applying the results of such research. It is important for us to begin with a clear understanding of what flexibility really is. To achieve this, we must critically evaluate previous attempts to define flexibility, formulate a new and improved definition of the term, draw a distinction between the two main components of flexibility, and discuss the different ways of demonstrating and measuring this parameter.

Previous Attempts to Define Flexibility The term "flexibility" has a number of different uses in the language, but it is clearly in the restricted, physiological sense that we are interested. All of the definitions we review here are intended to apply in this restricted sense. They fall into three groups: one-word definitions, range-of-motion definitions, and ability definitions. Each is prohlematic, and each will be examined in turn. This review is an expanded, updated version of one that we did a number of years ago. l In that initial review, we did not distinguish those definitions that were proposed by certain authors from those that were merely reported by them. Nor will we here, for when such definitions are used uncritically they are presumed adequate by default.

2

Introduction

One-Word Definitions One-word definitions are particularly problematic if not particularly common. Flexibility has been defined, more or less informally, as mobility, compliance, and-alternatively-as the "reciprocal counterpart" (i.e., the opposite) of stiffness. 2 The difficulties with such accounts are clear enough. First, the alleged synonyms are hardly synonymous. We can speak quite sensibly of structures being mobile (i.e., they can be moved) without being flexible. "Compliance" likewise suggests yielding to a wide variety of external demands, although the body complies with many such demands where flexibility is not in play, withstanding gravity and atmospheric pressure, for instance. Even if such terms were synonymous, we would still be in trouble, because the definitions would be uninformative, restating rather than providing an analysis of what the term means. Similarly, although the reciprocal counterpart of flexibility may indeed be stiffness (although perhaps "inflexibility" would be a better term), an analysis of the meaning of "flexibility" is still left wanting. Consider defining dryness as the reciprocal counterpart of wetness.

Range-of-Motion Definitions Most authors define flexibility either as range of motion,3 or, more precisely, as range of motion at or about ajoint (sometimes with other addenda, which do not bear mention).4 The latter is preferred because, by itself, range of motion is too broad. Structures other than anatomic joints, including very inflexible nonbiological structures (e.g., planets), may be said to have significant ranges of motion. A significant problem with these definitions is that they confuse the property in question (flexibility) with the criterion we use to measure it (range of motion). A joint's flexibility determines and is shown by its range of motion, but the two are not the same. Although range of motion (with appropriate addenda) may serve as a suitable operational definition, this qualification is seldom if ever acknowledged. We still need to know what flexibility is.

Ability Definitions Some definitions are apparently sensitive to the need to distinguish flexibility from the criterion of its measurement. According to these definitions, flexibility is the ability of a joint to move throughout its range of motion. s Obviously what is meant here is potential range of motion (also called com-

Flexibility: A Concise Guide

3

plete or full range of motion), because-very trivially-every joint is fully able to move throughout the range of motion it actually has, however wide or restricted the range, in which case all joints would be equally flexible. But if flexibility is the ability to move throughout a joint's potential range of motion, then any joint whose actual range falls short of that potential will fail to count as flexible at all, because it will lack, strictly speaking, the requisite ability. Because potential range of motion is a variable factor among others in determining flexibility, flexibility cannot be understood simply as relative to it. Either way, then, we are left with an implausible account: all joints are equally flexible, or almost no joint is flexible at all. The key problem here is one of phrasing, perhaps. Although the term "ability" is somewhat vague, it would be better to say that flexibility is the ability of a joint that determines its range of motion. The ability to do what, however? So put, we have not yet arrived at a clear enough sense of what flexibility is, nor have we addressed more general problems shared by these and other definitions.

General Problems Previous definitions also suffer from a number of problems irrespective of type. First, although many definitions indicate that range of motion is joint specific, this is often taken to mean range of motion at a single joint, excluding the cumulative flexibility of joint groups (e.g., the spine). Second, although some definitions acknowledge the role of body tissues in determining range of motion,6 we must be clear that flexibility simply is that determining property of those tissues. Third, hardly any definition includes the obvious caveat that movements within the range be achievable without injury.7 Perhaps the most serious shortcoming of previous definitions is the failure to specify the type of property that flexibility is. In a broad sense, flexibility is a physical property, a physiological property that body tissues have in virtue of their composition and structure. More precisely, it is a dispositional property. Just as the fragility of glass disposes it to break easily, the flexibility of tissues disposes them to allow excursions (movements) around joints. The greater the fragility of glass, the more easily it breaks; the more flexible a joint, the greater the range of motion.

A New Definition Having identified the various shortcomings of previous attempts, we now know what to avoid, and what to include, in a characterization of flexibility. Therefore, we offer the following definition (which uniquely makes no mention of range of motion):

4

Introduction

Flexibility is the disposition a of body tissues b to allow, without injury, excursionsd at a joint or set of joints. 8

C

a. This disposition is amenable to change. Various factors, including age, sex, injury, and lifestyle can affect it (see Chapter 7). When range restriction is caused by tension in soft tissue, the structures may, by means of intrinsic elasticity, return to a normal resting state even if an increase in range has been achieved through a stretching regimen or by some other means. b. The tissues include muscle, tendon, fascia (a kind of connective tissue in and around muscles), joint capsules, cartilage, ligament, bone, and various components of the nervous system (including neuromuscular spindles). c. There is an implied restorative capacity, a preserved functionality. For each motion, an excessive excursion may lead to dysfunction. Thus, flexibility, similar to any other physiological parameter, should be viewed as having limitations. d. By design, each joint and joint group allows specific movements to occur. Limits to each range of motion may include soft tissue contact, boneto-bone contact, ligament tension, and soft tissue tension.

Components, Demonstrations, and Measures Having characterized flexibility as a particular kind of disposition of body tissues, it is now appropriate to distinguish its fundamental components and to discuss, in rounding off the introduction, how this disposition is demonstrated and measured. Flexibility has two fundamental components, each of which belongs to a certain class of tissues: the contribution made by the joint tissues themselves (cartilage, capsule, ligament, and bone) and that made by the surrounding soft tissues (muscle, tendon, and fascia). The stability and basic function of joints are determined primarily by the first group, chiefly the joint capsule and surrounding ligaments, although the second group is also significantly involved, most notably the supportive fascia and musculature. By contrast, flexibility training should target only the surrounding soft tissues, because attempts to modify the joint tissues themselves hold little promise of improving performance, and may lead to significant injury besides. The contribution of joint tissues can be determined by two manual techniques, "joint play" and "end feel.,,9 When either excessive joint motion or

Flexibility: A Concise Guide

5

restriction is present, the assessments previously mentioned should be conducted by those who specialize in the field. Where a joint is inherently capable of continued motion, range may still be restricted by the surrounding soft tissues. Such restriction can be demonstrated by stretching the soft tissues to their limit. This can be done either passively, by applying external force, or actively, by the subject's own movement. lo When the subject's own movement is dynamic (ballistic, rapid, forceful), the achievable range may exceed that achieved by slow-tomoderate movement. Flexibility can be demonstrated by having the subject slowly assume positions that take the targeted tissues to the safe limits of their movement potentiality, by the application of external forces, or by dynamic motion. Slow/static stretching and yoga serve as examples of the first approach, gravitational force and pressure from a partner illustrate the second, and rapidly moving a body part through its complete (dynamic) range represents the last approach. Dynamic flexibility training refers to exercises that are brought about by rapid concentric contractions of the antagonist muscle group, creating sufficient momentum in the moved body part to cause a significant stretching effect of the agonist. The speeds possible in this form of stretching range from slow (low momentum) to ballistic (high momentum). The latter often achieves the greatest possible range, taking the soft tissues through an elastic energy storage-and-recoil event. It also presents the greatest possibility for injury. Direct measures of flexibility do not exist. Range of motion is used to represent it. This approach is referred to as flexibility testing and is routinely conducted by professionals in the health and human sciences. Although most assessments need only be performed by simple observation, more precise determinations (i.e., measurements) are often desirable. Such measurements are used in evaluating physical, occupational, and sportspecific fitness, diagnosing suboptimal function and injury, and monitoring the progress of conditioning and rehabilitative programs. In both laboratory and clinical settings, the vast majority of measurements are taken around a single axis of rotation (goniometry), or by a linear measurement, assessing multiple joints (sit-and-reach test). Many researchers use "still" photographs to determine static flexibility, and kinesiologists often USe video to examine dynamic flexibility. These simple planar, indirect measures are used despite the fact that many movements performed in sport and exercise (as well as in day-to-day activities) require motion about two or three axeS simultaneously. Although at present we lack direct, accurate, and reliable means of measuring flexibility under all conditions, it is hoped that new technologies will enable us to overcome this significant obstacle to both research and clinical work in this field.

6

Introduction

Currently there are no methods or apparati that can directly quantify flexibility. Goniometry, various types of protractors, and flexometers provide only indirect assessments. The limited number and poor quality of assessment techniques severely diminishes the opportunities to collect accurate information regarding flexibility.

Summary Previous attempts to define flexibility are of three types: one-word definitions, range-of-motion definitions, and ability definitions. Each of these approaches has been found to be inadequate. We propose a new definition: Flexibility is the disposition of body tissues to allow, without injury, excursions at a joint or set ofjoints. This property is measured by, but not equivalent to, range of motion. Both joint tissues and the surrounding soft tissues contribute to flexibility, although only the latter should be modified in attempts to enhance flexibility.

References 1. Holt et al. (1996a). 2. See, respectively, Corbin (1984), Hardy (1985), Sahrmann (1996), Shrier (2002). 3. Low (1976), Ekstrand et al. (1982), Prichard (1987), Schramm et al. (2001), Shrier (2002). 4. Holt (1974), Low (1976), Piscopo and Bailey (1981), Ekstrand et al. (1982), Smith (1982), van Gyn (1984) Kreighbaum and Barthels (1985), Prichard (1987), Saal (1987), Alter (1988), Anderson and Burke (1991), Bloomfield et al. (1992), National Strength and Conditioning Certification Commission (1997), Hedrick (2000), Dirckx (2001), Anderson et al. (2002), Shrier (2002), Soares de Araujo (2004). 5. Alter (1990), Wiksten and Peters (2000), American College of Sport Medicine (2000). 6. Dirckx (2001), Anderson et al. (2002). 7. Saal (1987) proposes that the excursions be achievable within limits of pain. However, the restriction offered here, as in Holt et al. (1996a), is much more appropriate. Flexibility implies the preserved functionality of the tissues, not necessarily the subject's comfort. 8. Adapted from Holt et al. (1996a). In our original formulation, we considered flexibility to be the "intrinsic physical property of body tissues that determines range of motion...." Our intent was to emphasize the underlying mechanism as well as the distinction between flexibility and range of motion. Although the distinction still holds, we did not get the formulation exactly right. Flexibility is the functional/dispositional property determined by the mechanism, and not

Flexibility: A Concise Guide

7

part and parcel of it (which intrinsic properties are), just as flexibility, in turn, determines, but is not equivalent to, range of motion. 9. Cyriax (1969), Kaltenborn (1988), Maitland (1988). See Chapter 10 for more detail on these techniques. 10. Holt et al. (1996a), Hedrick (2000).

1 Stretching Techniques and Exercise Prescriptions

Flexibility is similar to aerobic capacity, strength, and neuromuscular endurance in being a trainable fitness parameter. Research into proper exercise prescriptions for slow/static, yoga, and dynamic stretching does not yet exist. I Even basic guidelines for safe and effective use of these stretching techniques are generally missing. In this chapter, we fill this gap by offering practical guidelines for the use of yoga, slow/static, and dynamic stretching techniques, plus our scientifically based exercise prescription for the reversal of antagonists method (3S), a derivative of proprioceptive neuromuscular facilitation (PNF).

Yoga Yoga is a practice that originated in India thousands of years ago, and is one of the oldest forms of structured physical movement. Hatha (physical) yoga, the most popular type of yoga in Western society, consists of specific movemen t sequences that term inate in very characteristic postures (Asanas), whose purpose is to strengthen the major systems of the body (cardiorespiratory, nervous, immune, etc.). We prescind from comment on the spiritual objectives of such exercise. It is often claimed that the key to success with yoga is to adopt it as part of one's lifestyle, to respect one's physical limitations, to listen to one's body, and to adjust the adopted postures accordingly. Pain is not an option. A nonaggressive entry into each stretch is important, and once the terminal position is reached, focused breathing (4 reps) with complete exhalations is essential. By focusing on this breathing protocol, yoga practitioners believe the "linkages" between the brain and muscles are "quieted" or disengaged, permitting greater range of motion. Another possible explanation From: Musculoskeletal Medicine: Flexibility: A Concise Guide to Conditioning, Performance Enhancement, Injury Prevention, and Rehabilitation By L.E. Holt, T.W. Pelham, and J. Holt © Humana Press Inc.. Totowa. NJ 11

12

1. Stretching Techniques and Exercise Prescriptions FIGURE

1-1. The standard quadriceps stretch.

is that during exhalation, the musculature responsible for stabilizing the trunk is relaxed and all musculature that has an attachment to the trunk is placed in less tension, permitting greater range of motion. Relaxation and meditation are fundamental to the practice. In later chapters, we will present Hatha exercises that may be considered as an alternative to Western stretching methods.

Slow/Static Stretching Most slow/static stretching routines involve a series of 3 to 5 reps, each usually lasting 10 to 20 seconds, despite the fact that research has shown less than 30 seconds to be ineffective. The slow/static technique requires a controlled continuous movement to end range, which can be brought about by gravity or some other external force, a concentric contraction of the antagonists, or a combination of the two (slow phase). At end range, the participant holds the terminal position for the designated time. After the static hold phase, the participant returns to the starting position and then repeats the procedure. The quadriceps stretch is an example of a slow/static stretch protocol (Figure 1-1). Slow/static stretching is often used as part of a warm-up before exercise or sport. It can be used on all the major muscle groups, and is a simple and generally safe method. It may be practiced throughout the day, provided body tissues (such as the spine) are not vulnerable, as they can be early in the morning just after waking Up.2 At such times, care must be taken not to assume positions too quickly or create excessive tension, which may produce or predispose one to injury.

Dynamic Stretching Well-executed sport movements often involve the storage and release of elastic energy in concert with the proper timing of muscle contractions.

Flexibility: A Concise Guide

13

When synchronized properly, this can result in the rapid limb movements required for success in the vast majority of sports. Recently, dynamic stretching has been advocated as a superior sport-specific technique.' This form of stretching has a definite role to play in conditioning, but it should not, in our view, be used to increase elasticity, because it is ineffective at doing so. It is most effectively used to prepare already stretched tissues for the movements specific to the relevant sport. 3S (which we discuss later) is recommended early in the warm up to elicit the viscoelastic effect, whereas moderate dynamic stretching should be performed just before practice or performance. The workout or competition should be followed by a second bout of 3S. In slow/static (and traditional passive) stretching, the end-range position is held for a set period of time. However, very few sport/dance patterns involve such fixed positions. Slow/static and traditional passive stretching do not translate very well into functional, movement-specific flexibility. Such techniques may yield a viscoelastic effect, but only approximately 25% of the effect resulting from use of the 3S technique. Because there is little to support a link between slow/static flexibility (whether actively or passively achieved) and movement-specific performance, dynamic flexibility training, following a 3S series, is a more appropriate means of preparing for many sport activities. The most striking characteristics of dynamic stretching are the wide range of speeds possible and the variance in kinetic energy changes during each rep. It can be performed gently at relatively slow speeds, moderately at various intermediate speeds, or violently at very fast speeds. The body may be used as its own resistance, or resistance may be added in the form of extra weights, bars, or vests. Added resistance, especially when coupled with high velocity movements, often leads to injury. There is no set standard for such oscillations, which may vary in speed and force even within a given rep. Even so, dynamic stretching is a popular form of stretching in many sports, and it can be used successfully in a variety of conditioning programs. Dynamic stretching usually involves 5 to 15 reps. Consider how baseball players typically warm-up in the on-deck circle, swinging a weighted bat or heavy bar. Some consider dynamic stretching an ideal method for improving dynamic flexibility, others that it exposes the athlete to a high, unnecessary risk of injury. However, if it is performed progressively, under control, and without excessive resistance, dynamic stretching can be an important preparatory aid to performance. Pectoral stretch (Figure 1-2) and trunk rotation (Figure 1-3) illustrate dynamic stretches performed by many athletes involved in explosive sports. We stress caution when using dynamic stretching. It is safest and most useful when performed with very little resistance and at relatively slow speeds. This is particularly true for recreational athletes and those involved in fitness pursuits. Rapid dynamic movements should be performed only

14

1. Stretching Techniques and Exercise Prescriptions

FIGURE 1-2. Pectoral dynamic stretch. (A) start and return position. (B) fully stretched.

1-3. Trunk rotation dynamic stretch. (A) start and return position. (B) fully stretched, right.

FIGURE

after a set of progressively incremental stretches, with no abrupt decelerations, and with only such resistance as is appropriate to the activity or sport (e.g., unweighted bats). Figure 1-4 illustrates an inappropriate use of dynamic stretching.

1-4. Without any preparation, this athlete begins performing rapid, full-range rotations with a barbell.

FIGURE

Flexibility: A Concise Guide TABLE

15

1-1. Comparison of basic stretching techniques

Factor Effectiveness for increasing range of motion Risk of injury Degree of possible pain Resistance to stretch Effective preparation for specific activities Practicality (time needed, location, assistance)

Dynamic

Slow/static

PNF

Fair High High High Excellent Excellent

Good Low Medium-Low Medium Good Excellent

Excellent Low Medium-Low Low Excellent Good

Comparison of Slow/Static, Dynamic, and PNF Techniques Most comparative studies show that many of the PNF variations are superior to both slow/static and dynamic stretching methods,4 When properly executed, PNF techniques present little risk of injury, and are more effective in bringing the targeted muscle groups close to their current maximal responsive capacity. Table 1-1 summarizes the merits and disadvantages of the three basic stretching techniques. Many exercise specialists recommend using PNF or slow/static stretching, and recommend avoiding dynamic stretching because of the greater risk of injury and muscle pain, which result from the jerky, rapid movements characteristic of the method. We think that this is a mistake, however. There is a time and place for each of the various stretching protocols. Because dynamic movements are part of many sports, it seems obvious that some dynamic stretching before performance is desirable. The important factor is knowing when and how to use each method.

PNF Variations and Effects Many modified PNF techniques have been developed since Kabat's work in the 1950s,s and a number of these techniques are currently in use by athletes, therapists, and fitness enthusiasts. Common PNF varieties include: 1) hold-relax (isometric contraction in a lengthened position, without a subsequent concentric contraction of the antagonist); 2) contract-relax (in a lengthened position, concentric contraction of antagonist followed by relaxation and passive hold; 3) slow-reversal-hold-relax (isometric contraction in a lengthened position, then relaxation and concentric contraction of the antagonist followed by relaxation and passive hold); and 4) 3S, or (repeated) reversal ofantagonists (placing the agonist in a lengthened position, contracting isometrically against an immovable object, then contracting the opposite muscle group concentrically to further lengthen the stretched tissues).

16

1. Stretching Techniques and Exercise Prescriptions

Although PNF is the best general approach to stretching, not every variety of PNF is equally effective. One study, for instance, found the reversal of antagonists (3S) approach to be significantly more effective than the hold-relax approach. 6 Overall, 3S is the most effective variation of the PNF protocols. It has been shown to yield significant increases in flexibility and, via reciprocal inhibition, to promote muscle relaxation. 7 It has been recommended for use in both athletic and rehabilitative contexts,8 having successfully been used to improve flexibility not only in competitive athletes and injured individuals, but also in those unaccustomed to exercise, and in both the young and old, with varying levels of health. 9

Reversal of Antagonists (3S) The reversal of antagonists (hereafter 3S) technique, created as a sport/ fitness-specific PNF derivative, was first described in Scientific Stretching for Sport (3S).1O Athletes and dancers have used this method since the mid1970s as a means of preventing injury and augmenting achievable range of motion, and, thereby, enhancing performance mechanics and/or aesthetics. In addition to athletes and dancers, many individuals in physical and sport rehabilitation programs, as well as the general population, have been taught this protocol. Responses from clinics, the sports milieu, and the general public have been largely positive. 3S was originally designed as a manual, partner-assisted stretching technique; a partner was needed to provide the fixed resistance against which the lengthened agonist isometrically contracted at or near maximum (to use spindle facilitation). Because the isometric contraction was recommended (in most cases) to approach maximal effort, many thought that there would be a high risk of injury, unless the assisting partner was experienced. And so, naturally, an experienced partner was deemed essential for the safe, effective use of the 3S protocol. However, research during the past 10 years has shown that lighter contractions of the agonist yield the same increases without incurring the possible risks when maximal isometric contractions are resisted by an inexperienced partner. 11 A new device has been developed to simulate the original partner-assisted 3S method without need of a partner to provide resistance during the routine (Figure 1_5).12 This machine, the FlexAbility LE 1000, is a computer-controlled flexibility system, the only complete system for improving flexibility of the major muscle groups of the lower limbs. This machine was first described in detail in 1995. 13 In a number of independent studies using this device, it proved to be an excellent tool for controlled experimentation. 14 In a comparative study of partner- and machine-aided 3S, both implementations produced the expected significant improvement in all measures, and showed virtually no differences (see Appendix C for more on the 3S machine and research pertaining to it)Y

Flexibility: A Concise Guide

17

FIGURE 1-5. FlexAbility LE 1000 (Scientific Stretching Ltd., Halifax, Nova Scotia).

In the absence of a partner or 3S machine, an accessory device is a helpful way to use the 3S technique. The appropriate accessory device for solo 3S is a durable, strong and flexible band (Figure 1-6). The standard partnerassisted 3S is shown in Figure 1-7.

In a controlled experiment, significant improvements in flexibility were found for both partner-assisted and machine-assisted 35. Results were virtually the same on all measurements.

FIGU RE 1-6. An accessory device to perform the 3S hip extension/hamstrings exercise.

FIGURE 1-7. The 3S hip extension/hamstrings exercise with partner.

18

1. Stretching Techniques and Exercise Prescriptions

Exercise Prescription for 3S The protocol that will be presented below, a scientifically based exercise prescription for 3S, represents the culmination of three decades of research, together with our most up-to-date experiments. This safe and effective flexibility program will be presented under the following four subheadings: 1. Beginning position 2. Isometric contraction and release 3. Concentric contraction of the antagonist 4. Sets and reps per session

Beginning Position After ensuring that there are no contraindications to performing 3S, the protocol is first explained and demonstrated to the participant. Then the participant assumes a properly aligned posture for the first exercise, and the protocol may begin. Initially, the individual produces a concentric contraction of the antagonist to a point at which the agonist is put into a lengthened but pain-free position (Figure 1-7). An object (partner's shoulder) that provides fixed resistance is placed in opposition to the agonist.

Isometric Contraction and Release When the agonist is lengthened, the subject contracts it (isometrically) against the fixed resistance, beginning with a 4-second build-up followed by a 6-second hold at the desired intensity (usually less than maximum). The 4-second build-up is recommended to reduce the risk of injury. Longer durations are unneeded and sometimes uncomfortable, whereas shorter durations lead to an almost dynamic stretch. 16 Researchers have used a wide range of suggested durations for the perceived voluntary isometric contraction (PVIC), from 3 to 13 seconds. Based on our research, we recommend that the isometric contraction be held for 6 seconds, which will yield the same effect as longer contractionsY Shorter durations for the build-up and hold (3-5 total seconds) tend to rush the individual, with the result that the target muscle can over-fire. That is why we recommend a 6-second hold. Another important factor in this stage of the 3S method is the intensity of the isometric contraction. Previous PNF stretching techniques stressed the importance of perceived maximum (or near maximum) voluntary isometric contractions (PMVIC) to elicit the greatest improvements. However, we found that, after 2 weeks, both 100% and 50% PMVIC (machine measured) routines produced similar changes in range of motion. 18 Furthermore, we compared a progressive program from 50% to 80% PMVIC

Flexibility: A Concise Guide

19

TABLE 1-2. 7-dayand 14-day progressive flexibility programs" 7-day program Day 1&2 Day 3 & 4 Day 5 & n Day 7

50% 00% 70% 80%

Perceived Perceived Perceived Perceived

maximum maximum maximum maximum

isometric isometric isometric isometric

contraction contraction contraction contraction

14-day program Days 1-4 Days 5-8 Days 9-12 Days 13 & 14

50% 60% 70% 80%

Perceived Perceived Perceived Perceived

maximum maximum maximum maximum

isometric isometric isometric isometric

contraction contraction contraction contraction

"All contractions to be performed without pain. All musculature except spinal column. Stretches of spinal column musculature are always performed at low intensities.

(machine measured) with a standard 100% PMVIC program and found identical improvements. IY Because a graded program is safer and no less effective than the standard near-maximum PMVIC approach, the former is recommended for this protocol (Tables 1-2 and 1-3). We also recommend that such a program be tailored to the subject's particular needs and restrictions (the therapeutic application of this type of progressive stretching program is discussed in Chapter 9).

Concentric Contraction of the Antagonist After the isometric contraction of the agonist, the individual is instructed to completely relax the muscle for 2 seconds. After this brief relaxation intervaL the individual produces a strong 3-second concentric contraction of the antagonist that stretches the agonist. The participant is encouraged

TABLE 1-3. 7-day and 14-day progressive flexibility program for the vertebra Is" 7-day program Day I Day 2 Day 3 Day 4 Day 5 Day n Day 7 14-day program Days 1-4 Days 5-8 Days 9-12 Days 13 & 14

20% 20%

30% 30%

40% 40% 50% 20% 30%

40% 50%

"All contractions to be performed without pain.

Perceived Perceived Perceived Perceived Perceived Perceived Perceived

maximum maximum maximum maximum maximum maximum maximum

isometric isometric isometric isometric isometric isometric isometric

contraction contraction contraction contraction contraction contraction contraction

Perceived Perceived Perceived Perceived

maximum maximum maximum maximum

isometric isometric isometric isometric

contraction contraction contraction contraction

20

1. Stretching Techniques and Exercise Prescriptions

to increase the intensity of the antagonist contraction commensurate with the increase in agonist isometric effort. Movements should always be smooth and controlled, not jerky or ballistic. Very light partner pressure may be applied if the exercising person has achieved a "release" (viscoelastic effect) but is unable to move to a new position using only antagonist contraction. This usually occurs when the agonist muscle group has reached ultimate end range and the antagonist is in an excessively shortened position. For example, the hip flexors may be incapable of producing enough tension to further flex the hip and further stretch the hamstrings (Figure 1-8).

Sets and Reps per Session Our research has consistently found that a series of 4 reps of the 3S stretching protocol is the most effective and efficient at improving and then maintaining range of motion?O Small improvements may occur with further reps, but the benefits are minimal. We think that nearly all of the elasticity changes occur with the first 4 reps, and the process involves a progression from larger to smaller viscoelastic restructuring. A number of factors must be considered in determining the appropriate number of stretching sessions per day and per week: 1) the flexibility status of the individual at that particular time; 2) the nature of the physical activity trained for; 3) the objectives of the fitness program; 4) the volume and intensity of training at that point in the cycle; 5) the interactive training modes (e.g., strength, aerobic, speed, skill, etc.); and 6) the specific needs of the subject. 2! For those in serious preparation for sport or dance, we recommend at least two sessions per day, one before and one after each workout, practice, or game. A more extensive stretching regimen may be helpful if the activity involves significant time delays in practice or competition (e.g., track and field), or if the activity is repetitive and, therefore, tends to cause tightening or cramping of the exercised muscles (e.g., cycling, jogging, or soccer). Sets and reps for rehabilitation are discussed in Chapter 9.

1-8. In the terminal position of the 3S hip extension/hamstrings exercise, the agonist (hip extensors/hamstrings) are fully lengthened, and the shortened antagonist (hip flexors), now in a mechanical disadvantage, cannot generate torque. In extreme sport positions and movements, large displacement in hip flexion is often accompanied by excessive lumbar flexion.

FIGURE

Flexibility: A Concise Guide

21

In summary, the 3S protocol involves a series of 4 reps, each lasting 15 seconds (4-second build-up, 6-second contraction, 2-second relaxation, and 3-second readjustment), 1 minute in total per muscle group. The 3S technique is a continuous, repeated reversal of antagonists exercise, in that each subsequent rep begins at the final angular position of the previous rep. The nature of this design may be partly responsible for the viscoelastic changes in the epimysium, perimysium, endomysium, and the musculotendinous junctions (detailed in Chapter 10) that result in 3S being three to four times more effective than the slow/static or dynamic stretching techniques.

Summary We recommend that the 3S approach be used when significant increases in flexibility are needed or must be maintained. Slow/static stretching is adequate for everyday workouts, and in cases in which time constraints, or the lack of a partner, machine, or accessory device makes 3S unfeasible. We recommend yoga for a combined relaxation/meditation effect, and controlled dynamic stretching just before any vigorous sport or dance participation, preferably after a bout of 3S, but acceptably after a slow/static or yoga routine. A second bout of stretching should follow the activity.

Contraindications: What Not To Do • The use of excess force by a partner or device that creates extreme tension in soft tissues is never recommended (Figs. 1-9 and 1-10). • Placing unnecessary stress on joint capsules, ligaments, or articulating surfaces is never recommended (Fig. 1- Jl).

FIGURE 1-9. Passive partner stretching. Forceful stretch on hamstrings.

FIGURE 1-10. Passive partner stretching. Forceful stretch on lumhar and thoracic tissues.

22

1. Stretching Techniques and Exercise Prescriptions FIGURE 1-11. Excessive stress on ligaments, joints, and articulating surfaces.

References 1. 2. 3. 4.

5. 6. 7. 8. 9. 10. 11. 12. 13.

14. 15. 16. 17. 18. 19. 20. 21.

Holt et al. (1996d). McGill (2000). Hedrick (2000), Fredrick and Szymanske (2001). Holt et al. (1970), Sady et al. (1982), Holt and Smith (1983), Prentice (1983), Cornelius and Jackson (1984), Greipp (1985), Wallin et al. (1985), Etnyre and Abraham (1986), Anderson and Burke (1991), McAtee (1993), Holt et al. (1996c), Pelham et al. (2002a). Kabat (1952), Kabat (1958). Holt and Smith (1983). Holt and Smith (1983), Pelham et al. (2002c). Holt (1974), McAtee (1993). Holt et al. (1996c). Holt (1974). Schmitt et al. (1999). The FlexAbility LE 1000 was developed by the senior author in association with Scientific Stretching, Ltd. of Halifax, Nova Scotia. Holt et al. (1995). Gleim and McHugh (1997), Gribble et al. (1999). Burke (1995). Schmitt et al. (1999), Pelham et al. (2000). Pelham et al. (2002b). Pelham et al. (2001). Schmitt et al. (1999). Schmitt et al. (1998), Schmitt et al. (1999). Pelham (1994a).

2 Stretching the Major Muscle Groups of the Lower Limb

In this chapter, we present appropriate stretching exercises for the major muscle groups of the lower limb. All four methods (3S, yoga, slow/static, and dynamic) are covered.* The method referred to as passive partner stretching (Figures 1-9 and 1-10) is often used in therapeutic settings. We do not recommend its use in recreational activities, fitness programs, or in sport, and is omitted from this and the following chapters on general stretching exercises. For more on therapeutic stretching techniques, see Chapter 9.

*Exercises to be done on both limbs.

From: Musculoskeletal Medicine: Flexibility: A Concise Guide to Conditioning,

Performance Enhancement, Injury Prevention, and Rehabilitation By L.E. Holt, T.W. Pelham, and J. Holt © Humana Press Inc.. Totowa, NJ

23

24

2. Stretching the Major Muscle Groups of the Lower Limb

Exercise I-Hip Extensors (3S Method) 2-1. Muscles to be stretched (biceps femoris, semimembranosus, semitendinosus, and gluteus maximus). It should be remembered that isometric contractions of 60% maximum voluntary isometric contractions (MVIC) or greater will maintain the isometric strength capabilities of the muscle group being stretched (agonist). FIGURE

~ \".

,

" I

..•..,

..

~

'·--f·-:

..,.

n

I '

I

2-2. 3S hip extensor stretch (position and initial phase of exercise). The individual being stretched (S) is lying on his/her back, with one leg on the floor, the other leg raised as high as possible, (pain free) both legs remain straight throughout the exercise. The partner (P) is on one knee, with the opposite foot on the floor and the shoulder against the back of the exercise leg. P holds the non-exercising leg to the floor. FIGURE

2-3. 3S hip extensor stretch (position and middle isometric phase of exercise). During the isometric phase, S contracts the hip extensors/hamstrings against P. That is, S attempts to push his/her raised leg to the floor. P resists this effort, causing an isometric contraction. After a 4-second build-up and a 6-second submaximal contraction, S relaxes the hip extensors/hamstrings (2 seconds). FIGURE

2-4. 3S hip extensor stretch (position and end phase of repetition 1). Next, S pulls the leg (hip flexion) toward his/her head by concentrically contracting the hip flexors. P assists with light pressure (reposition phase). This takes 3 seconds, for a total of 15 seconds. The hip extensors/hamstrings are in the new lengthened position. Repeat the procedure 3 times from the new lengthened positions. 4 reversal of antagonists, each taking 15 seconds, are performed, for a total of 60 seconds. FIGURE

Flexibility: A Concise Guide

Exercise I-Hip Extensors (Alternative Methods) FIGURE 2-5. Yoga stretch. From a kneeling position, slowly assume the posture depicted. Perform a series of slow inhalations/exhalations, stretching further with each exhalation (30+ seconds).

FIGURE 2-6. Slow/static stretch. S is lying on back (knees, back, and head are supported). In a slow and smooth motion, S flexes at the hip the (straight) leg to be stretched (direction of arrow). The hands (or towel) are placed behind the hamstring for support. S moves the leg as far as possible (pain free). S holds end position for 30+ seconds, then returns to the initial position. S repeats the above procedure on the opposite side. A total of 3 stretches per side are performed. Note: do not move the head forward during the motion.

FIGURE 2-7. Dynamic stretch (start and finish position of exercise). From supine position lying flat on mat.

FIGURE 2-8. Dynamic stretch (position at full stretch). Flex one hip at the desired speed to end of range. Return to start and repeat (5 to 10 reps).

25

26

2. Stretching the Major Muscle Groups of the Lower Limb

Exercise 2-Hip Adductors (3S Method) 2-9. Muscles to be stretched: adductor brevis, adductor longus, adductor magnus, gracilis, and pectineus).

FIGURE

2-10. 3S hip adductor stretch (position and initial phase of exercise). S is sitting with ideal back posture, legs straight and as far apart as possible. P is positioned in front of S, resting on one knee with the opposite foot on the floor, holding both S's legs above the ankles. FIGURE

FIGURE 2-11. 3S hip adductor stretch (position and middle isometric phase of exercise). S attempts to bring her/his legs together (adduct hips), knees remain straight, limbs remain in neutral position, back posture is maintained. P resists.

2-12. 3S hip adductor stretch (position and end phase of exercise). After the 4-second build-up and a 6second submaximal isometric contraction, S relaxes for 2 seconds, then spreads his/her legs (abducts hip joints) 3 seconds. P assists with light pressure. The hip adductors are in the new lengthened position. Repeat the procedure 3 times from the new lengthened positions. FIGURE

Flexibility: A Concise Guide

Exercise 2-Hip Adductors (Alternative Methods) FIGURE 2-13. Yoga stretch. From sitting position, slowly assume posture depicted. Perform a series of slow inhalations/ exhalations, stretching further with each exhalation (30+ seconds).

FIGURE 2-14. Slow/static stretch (position of exercise). S is sitting maintaining an ideal posture. ln a slow and smooth motion. S spreads (direction of arrows), legs as far as possible (pain free). S holds end position for 30+ seconds before returning to initial position. S repeats the procedure 3 times.

FIGURE 2-15. Dynamic stretch (start and finish position of exercise). Lying supine, hands by side. legs vertical.

FIGURE 2-16. Dynamic stretch (position at full stretch). Abduct both legs simultaneously at the desired speed (5 to 10 reps).

27

28

2. Stretching the Major Muscle Groups of the Lower Limb

Exercise 3-Hip Flexors (3S Method) FIGURE 2-17. Muscles to be stretched (iliacus, pectineus, psoas, rectus femoris, and sartorius).

2-18. 3S hip flexor stretch (position and initial phase of exercise). S is lying prone with the exercise leg flexed at the knee and raised as high as possible (pain free). P is behind S, resting on one knee, with the opposite foot on the floor slightly above the left buttock, holding the lower thigh and pressing down on S's posterior pelvis.

FIGURE

2-19. 3S hip flexor stretch (position and middle isometric phase of exercise). S attempts to pull his/her knee downward to the floor. P resists. FIGURE

2-20. 3S hip flexor stretch (position and end phase of exercise). After the 4-second build-up and a 6-second submaximal contraction, S relaxes for 2 seconds, then lifts the leg higher (3 seconds). P assists with light pressure. The hip flexors are in the new lengthened position. This increased range also involves anterior pelvic tilt and lumbar hyperextension. Repeat the procedure 3 times from the new lengthened positions. FIGURE

Flexibility: A Concise Guide

Exercise 3-Hip Flexors (Alternative Methods) FIGURE 2-21. Yoga stretch. Assume lunge position. arms overhead as depicted. Perform a series of slow inhalations/exhalations. stretching further with each exhalation (30+ seconds).

FIGURE 2-22. Slow/static stretch (position of exercise). S in semi-lunge position, maintaining ideal back posture. In a slow and smooth motion, S further flexes the forward leg. maintaining the back knee on the floor. The hands may be used for stability. S avoids rotating the pelvis. S moves forward (direction of arrow) as far as possible (pain free). S holds end position for 30+ seconds before returning to initial position. S repeats the procedure on the opposite side. A total of 3 stretches per side are performed.

FIGURE 2-23. Dynamic stretch (start and finish position of exercise). Normal standing posture.

FIGURE 2-24. Dynamic stretch (position at full stretch). Extend hip joint, at desired speed maintain balance by angling trunk forward (5-10 reps). Some anterior tilt and lumbar hyperextension will accompany this activity.

29

30

2. Stretching the Major Muscle Groups of the Lower Limb

Exercise 4-Hip Inward (Medial) Rotators (3S Method) 2-25. Muscles to be stretched (adductor magnus, gluteus medius, gluteus minimus, and tensor fascia lata). Hip architecture varies considerably. Many individuals will not achieve large ranges of motion. Most people do not need to stretch this muscle group.

FIGURE

FIGURE 2-26.

3S hip inward rotator stretch (position and initial phase of exercise). S is lying on his/her back, one leg straight and on the floor. The exercise leg is positioned with the thigh nearly vertical, knee flexed, and the hip outwardly rotated as far as possible. When hip is outwardly rotated and the knee is flexed, the foot moves in toward the body. P is in front and to the side of S, resting on one knee, with the opposite foot on the floor, holding the knee and ankle of the exercise leg.

FIGURE 2-27.

3S hip inward rotator stretch (position and middle isometric phase of exercise). S attempts to inwardly rotate his/her hip (tries to push his/her foot out and away from his/her body). P resists. FIGURE 2-28.

3S hip inward rotator stretch (position and end phase of exercise). After the 4-second build-up and a 6second submaximal isometric contraction, S relaxes for 2 seconds, then inwardly rotates his/her hip 3 seconds. P assists with light pressure. The hip inward rotators are in the new lengthened position. Repeat the above procedure 3 times from the new lengthened positions.

Flexibility: A Concise Guide

Exercise 4-Hip Inward (Medial) Rotators (Alternative Methods) FIGURE 2-29. Yoga stretch. From a sitting position. assume position as depicted. Perform a series of inhalations/exhalations. stretching fur-ther with each exhalation (30+ seconds). Because of architecture variability in the hip joints, many may find this to be a difficult position.

FIGURE 2-30. Slow/static stretch (position of exercise). S is standing on one leg as shown. Knee and hip flexed to 90°, opposite hand holding exercise ankle. S holds end position for 30+ seconds, then returns to initial position. S repeats the procedure for a total of 3 stretches for each leg.

FIGURE 2-31. Dynamic stretch (start and finish position of exercise). Supine lying position. with one leg flexed at hip and knee. as depicted.

FIGURE 2-32. Dynamic stretch (position at full stretch). Externally rotate hip joint, as depicted, at desired speed (5-10 reps).

31

32

2. Stretching the Major Muscle Groups of the Lower Limb

Exercise 5-Hip Outward (Lateral) Rotators (3S Method) 2-33. Muscles to be stretched (gluteus maximus, obturator externus, obturator internus, piriformis, quadratus femoris, gemelli superior, gemelli inferior, and sartorius). Stretching this muscle group is not needed by the vast majority of participants.

FIGURE

FIGURE 2-34. 3S hip outward rotator stretch (position and initial phase of exercise). S is lying on his/her back, one leg straight and on the floor, the exercise leg is positioned with the thigh nearly vertical, knee flexed, and the hip inwardly rotated as far as possible (pain free). When the hip is inwardly rotated and the knee is flexed, the foot swings away from the body. P is in front and to the side of S, resting on one knee, with the opposite foot on the floor, holding the knee and ankle of the exercise leg.

FIGURE 2-35. 3S hip outward rotator stretch (position and middle isometric phase of exercise). S attempts to outwardly rotate his/her hips (tries to push his/her foot in toward his/her body). P resists. FIGURE 2-36. 3S hip outward rotator stretch (position and end phase of exercise). After the 4-second build-up and a 6-second isometric submaximal contraction, S relaxes for 2 seconds, then inwardly rotates his/her hip for 3 seconds. P assists with light pressure. The hip outward rotators are in the new lengthened position. Repeat the above procedure 3 times from the new lengthened positions.

Flexibility: A Concise Guide

Exercise 5-Hip Outward (Lateral) Rotators (Alternative Methods) FIGURE 2-37. Yoga stretch. From a prone lying position. as depicted, perform a series of inhalations/exhalations, stretching further with each exhalation (30+ seconds). Stretching this muscle group is not needed by the vast majority of participants.

FIGURE 2-38. Slow/static stretch (position of exercise). S is lying on his/her back, hip and knee flexed to 90° Hip is rotated inwardly, as shown. S holds end position for 30+ seconds, then returns to initial position. S repeats the procedure to the opposite side. A total of3 stretches per side are performed.

FIGURE 2-39. Dynamic stretch (start and finish position of exercise). Supine lying, one leg flexed at hip and knee, as depicted.

FIGURE 2-40. Dynamic stretch (position at full stretch). Internally rotate the hip joint, as depicted, at the desired speed (5-1 0 reps).

33

34

2. Stretching the Major Muscle Groups of the Lower Limb

Exercise 6-Plantar Flexors (3S Method) 2-41. Muscles to be stretched (gastrocnemius, soleus, and plantaris).

FIGURE

2-42. 3S plantar flexor stretch (position and initial phase of exercise). S is in a long sitting position, knees straight, back in ideal posture, hands grasping the ends of a towel or belt, foot and toes pulled up toward head (dorsi flexed) as far as possible (pain free).

FIGURE

2-43. 3S plantar flexor stretch (position and middle isometric phase of exercise). S attempts to point her feet (plantar flex), and resists this with her own effort.

FIGURE

FIGURE 2-44. 3S plantar flexor stretch (position and end phase of exercise). After a 4-second build-up and a 6-second submaximal isometric contraction, he/she relaxes for 2 seconds, then pulls his/her foot and toes up as far as possible (pain free) for 3 seconds, and assists with light pressure from towel. The plantar flexors are in the new lengthened position. Repeat the procedure 3 times from the new lengthened positions.

Flexibility: A Concise Guide

Exercise 6-Plantar Flexors (Alternative Methods) FIGURE 2-45. Yoga stretch. In long sitting position, dorsiflex the ankles, as depicted. Perform a series of inhalations/exhalations, stretching further with each exhalation (30+ seconds).

FIGURE 2-46. Slow/static stretch (position of exercise). Slowly position as depicted, keeping heel down. Hold (30+ seconds), repeat twice more. Change legs and repeat.

FIGURE 2-47. Dynamic stretch (start and finish position of exercise). Standing erect on step.

FIGURE 2-48. Dynamic stretch (position at full stretch). Allow gravity to drop body at the desired speed and return (5-10 reps).

35

3 Stretching the Major Muscle Groups of the Upper Limb

In this chapter, we present appropriate stretching exercises for the major muscle groups of the upper limb. All four methods (3S, yoga, slow/static, and dynamic) are covered. *

*Exercises to be done on both limbs.

From: Musculoskeletal Medicine: Flexibility: A Concise Guide to Conditioning, Performance Enhancement, Injury Prevention, and Rehabilitation By L.E. Holt, T.W. Pelham, and J. Holt © Humana Press Inc., Totowa, NJ 37

38

3. Stretching the Major Muscle Groups of the Upper Limb

Exercise 7-Shoulder Extensors (3S Method) 3-1. Muscles to be stretched (latissimus dorsi, teres major, and pectoralis major [sternocostal head]). It should be remembered that isometric contraction of 60% maximum voluntary isometric contractions (MVIC) or greater will maintain the isometric strength capabilities of the muscle group being stretched (agonist). FIGURE

FIGURE 3-2. 3S shoulder extensor stretch (position and initial phase of exercise). S is in a long sitting position, legs straight, with ideal back posture, arms straight, shoulders stretched (flexed) as far as possible (pain free). P is standing behind S, one foot near S's body, with that knee resting against S's spine (use of pad or towel may prove helpful). P holds both forearms.

3-3. 3S shoulder extensor stretch (position and middle isometric phase of exercise). S attempts to pull his/her arms toward his/her legs (extend shoulders), elbows remaining straight. P resists. FIGURE

FIGURE 3-4. 3S shoulder extensor stretch (position and end phase of exercise). After a 4-second build-up and a 6-second submaximal isometric contraction, S relaxes for 2 seconds, then pushes arm backward (flexes shoulders) for 3 seconds. P assists with light pressure. The shoulder extensors are in the new lengthened position. Repeat the procedure 3 times from the new lengthened positions.

Flexibility: A Concise Guide

39

Exercise 7-Shoulder Extensors (Alternative Methods) FIGURE 3-5. Yoga stretch. From a long sitting position. assume posture depicted. Perform a series of slow inhalations/exhalations, stretching further with each exhalation (30+ seconds).

FIGURE 3-6. Slow/static stretch (position of exercise). S is standing, maintaining ideal posture throughout the exercise. S, in a slow and smooth motion. flexes (direction of arrow) arms as far as possible (pain free). S holds end position for 30+ seconds. S returns to initial position, and repeats the procedure 3 times. Note: do not move head forward.

FIGURE 3-7. Dynamic stretch (start and finish position of exercise). Begin in normal standing position.

FIGURE 3-8. Dynamic stretch (position at full stretch). Flex both shoulder joints at the desired speed to end range. Return to start and repeat (5-10 reps). By isometrically contracting the abdomina Is, S can control the tendency to increase the lordotic curve in the lumbar region.

40

3. Stretching the Major Muscle Groups of the Upper Limb

Exercise 8-Shoulder Horizontal Adductors (3S Method) 3-9. Muscles to be stretched (pectoralis major, anterior deltoid, and coracobrachialis). FIGURE

FIGURE 3-10. 3S shoulder horizontal adductors (position and initial phase of exercise). S is in a long sitting position, legs straight, with ideal back posture, and arms raised to shoulder level and horizontally abducted, with elbows straight. P is standing behind S, one foot near S's body, with that knee resting against S's spine (use of pad or towel may prove helpful). P is holding both forearms.

3-11. 3S shoulder horizontal adductors stretch (position and middle isometric phase of exercise). S attempts to pull his/her arms forward (horizontal adduction), keeping his/her elbows straight. P resists. FIGURE

FIGURE 3-12. 3S shoulder horizontal adductors stretch (position and end phase of exercise). After 4-second buildup and 6-second submaximal isometric contraction, S relaxes for 2 seconds, then pushes arms backward for 3 seconds; P assists with light pressure. The shoulder extensors are in the new lengthened position. Repeat the procedure 3 times from the new lengthened positions.

Flexibility: A Concise Guide

Exercise 8-Shoulder Horizontal Adductors (Alternative Methods) FIGURE 3-13. Yoga stretch. From a standing position, assume the posture depicted. Perform a series of slow inhalations/exhalations, stretching further with each exhalation (30+ seconds).

FIGURE 3-14. Slow/static stretch (position of exercise). S is standing throughout the exercise. S, in a slow and smooth motion, horizontally abducts (direction of arrow) arm(s) at 45° angle or higher, as far as possible (pain free). S holds end position for 30+ seconds, then returns to initial position. S repeats the procedure 3 times. Notes: as S becomes comfortable with the exercise, the arm is gradually raised to shoulder level. Do not move the head forward during the motion.

FIGURE 3-15. Dynamic stretch (start and finish position of exercise). Begin standing with both shoulder joints flexed to 90°, as depicted.

FIGURE 3-16. Dynamic stretch (position at full stretch). Horizontally abduct both shoulder joints simultaneously to end range. Return to start and repeat (5 to 10 reps).

41

42

3. Stretching the Major Muscle Groups of the Upper Limb

Exercise 9-Shoulder Inward (Medial) Rotators (3S Method) 3-17. Muscles to be stretched (pectoralis major, latissimus dorsi, teres major, and subscapularis). This should be performed at low intensities of the isometric contractions.

FiGURE

3-18. 3S shoulder inward rotators (position and initial phase of exercise). S is standing erect, arm raised to shoulder level, elbow flexed to 90°, shoulder outwardly rotated as far as possible (pain free). P is standing in front and to the side of S. one hand on S's wrist, the other on S's arm, slightly above the elbow. FIGURE

3-19. 3S shoulder inward rotators stretch (position and middle isometric phase of exercise). S attempts to rotate shoulder inwardly (throwing motion). P resists.

FIGURE

3-20. 3S shoulder inward rotators (position and end phase of exercise). After 4-second build-up and a 6-second isometric contraction, S relaxes for 2 seconds, then rotates shoulder outwardly 3 seconds. P assists with light pressure. The shoulder inward rotators are in the new lengthened position. Repeat the procedure 3 times from the new lengthened positions. FIGURE

Flexibility: A Concise Guide

Exercise 9-Shoulder Inward Rotators (Alternative Methods) FIGURE 3-21. Yoga stretch. From a kneeling position, assume the posture depicted. Perform a series of slow inhalations/exhalations, stretching further with each exhalation (30+ seconds).

FIGURE 3-22. Slow/static stretch (position of exercise). S is lying on back (knees, back, and neck are supported). The shoulder is on the edge of plinth, the arm is free hanging. The arm is raised to shoulder level and horizontally abducted. The elbow is flexed to 90 [n a slow and smooth motion, S externally rotates (direction of arrow) shoulder as far as possible (pain free). S holds end position for 30+ seconds. S returns to initial position. S repeats the procedure three times. 0

•

FIGURE 3-23. Dynamic stretch (start and finish position of exercise). Standing as depicted, shoulder and elbow at 90°

FIGURE 3-24. Dynamic stretch (position at full stretch). Externally rotate shoulder joint as indicated at the desired speed. Return to start and repeat (5-10 reps).

43

44

3. Stretching the Major Muscle Groups of the Upper Limb

Exercise 10-Wrist Flexors (3S Method) 3-25. Muscles to be stretched (flexor carpi radialis, flexor carpi ulnaris, palmaris longus, flexor digitorum superficialis, and flexor digitorum profundus).

FIGURE

3-26. 3S wrist flexors (stretch position and initial phase of exercise). Assume position as depicted.

FIGURE

FIGURE 3-27. 3S wrist flexors stretch (position and middle isometric phase of exercise). S attempts to flex the wrist, while resisting his/her own efforts.

3-28. 3S wrist flexors stretch (position and end phase of exercise). After 4-second build-up and a 6-second isometric contraction, S relaxes for 2 seconds, then extends the wrist for 3 seconds. May apply light pressure. The wrist flexors are in the new lengthened position. Repeat the procedure 3 times from the new lengthened positions. FIGURE

Flexibility: A Concise Guide

Exercise IO-Wrist Flexors (Alternative Methods) FIGURE 3-29. Yoga stretch. Combining wrist flexor and hip inward rotators.

3-30. Slow static stretch (position of exercise). S is kneeling, upper body supported by hands, wrists in hyperextension. S slowly shifts forward, placing wrist flexors in gentle stretch, holds this position for 30+ seconds. S repeats the procedure 3 times.

FIGURE

3-31. Dynamic stretch (start and finish position of exercise). Standing as depicted, wrists flexed. FIGURE

FIGURE 3-32. Dynamic stretch (position at full stretch). Hyperextend both wrists to end range at the desired speed. Return to start and repeat (5-10 reps).

45

4 Stretching the Major Muscle Groups of the Trunk and Neck

In this chapter, we present appropriate stretching exercises for the major muscle groups of the trunk and neck. All four methods (3S, yoga, slow/ static, and dynamic) will be covered for the trunk. For the neck, we recommend a very gentle, active range of motion stretch.

From: Musculoskeletal Medicine: Flexibility: A Concise Guide to Conditioning, Performance Enhancement, Injury Prevention, and Rehabilitation By L.E. Holt, T.W. Pelham, and J. Holt © Humana Press Inc., Totowa, NJ

47

48

4. Stretching the Major Muscle Groups of the Trunk and Neck

Exercise ll-Trunk Extensors (3S Method) 4-1. Muscles to be stretched (erector spinae [iliocostalis, longissimus, and spinalis]; multifidus; and semispinalis thoracis). Only highly trained athletes should use 50% or greater perceived maximum (or near maximum) voluntary isometric contractions (PMVIC). FiGURE

4-2. 3S trunk extensors stretch (position and initial phase of exercise). S is in a long sitting position, legs straight, trunk relatively straight and angled forward (pelvic anterior tilt) as far as possible (pain free). P is positioned behind and slightly to the side of S, hands on S's upper back. Rear foot should be braced.

FIGURE

4-3. 3S trunk extensors (position and middle isometric phase of exercise). S slowly and carefully attempts to straighten up (extend trunk). P resists. Note that these exercises should be performed with the back relatively straight, with very low intensity isometric contraction until the individual is accustomed to them and is confident no injury will result. See Table 1-2 for 7- and 14-day programs for directions on intensity. FiGURE

4-4. 3S trunk extensors stretch (position and end phase of exercise). After a 4-second build-up and a 6-second isometric contraction, S relaxes for 2 seconds, then pulls himself/herself down toward his/her legs for 3 seconds. P applies no pressure. The trunk extensors are in the new lengthened position (subject should avoid excess lumbar flexion to achieve more range; trunk should remain relatively straight throughout the protocol). Repeat the procedure 3 times from the new lengthened positions. FiGURE

Flexibility: A Concise Guide

Exercise II-Trunk Extensors (Alternative Methods) FIGURE 4-5. Yoga stretch. Slowly assume the "fetal" position depicted. Perform a series of slow inhalations/exhalations, stretching further with each exhalation (30+ seconds).

FIGURE 4-6. Slow/static stretch (position of exercise). Assuming a kneeling position, as depicted, S goes as far as possible (pain free). S holds end position for 30+ seconds. S returns to initial position, and repeats the procedure 3 times.

FIGURE 4-7. Dynamic stretch (start and finish position of exercise), from the seated position depicted, legs apart.

FIGURE 4-8. Dynamic stretch (position at full stretch). Flex the trunk forward and downward at slow speed to end range and return. Repeat (5-10 reps). This exercise should only be used by athletes with specific need for ballistic stretching of this muscle group.

49

50

4. Stretching the Major Muscle Groups of the Trunk and Neck

Exercise 12-Trunk Lateral Flexors (3S Method) 4-9. Muscles to be stretched (same-side external and internal oblique, quadratus lumborum, iliocostalis lumborum, and longissimus thoracis). FIGURE

FIGURE 4-10. 3S trunk lateral flexors stretch (position and initial phase of exercise). S is standing, feet shoulder width apart, one arm overhead, bending trunk to one side. P is standing to the side, one hand on S's waist, the other holding S's raised upper arm.

4-11. 3S trunk lateral flexors (position and middle isometric phase of exercise). S attempts to pull his/her body to an upright position. P resists. FIGURE

FIGURE 4-12. 3S trunk lateral flexors stretch (position and end phase of exercise). After the 4-second build-up and a 6-second submaximal isometric contraction, S relaxes for 2 seconds, then pulls his/her trunk downward, with gravity assisting, for 3 seconds. The trunk lateral flexors are in the new lengthened position. Repeat the procedure 3 times from the new lengthened positions.

Flexibility: A Concise Guide

Exercise 12-Trunk Lateral Flexors (Alterna tive Methods) FIGURE 4-13. Yoga stretch. Assume position depicted. Perform a series of slow inhalations/exhalations, stretching further with each exhalation (30+ seconds).

FIGURE 4-14. Slow/static stretch (position of exercise). From a standing position. slowly laterally flex the trunk, as shown. The movement continues as far as possible (pain free). S holds end position for 30+ seconds. S returns to initial position. and repeats the procedure on the opposite side. A total of 3 stretches per side are performed.

FIGURE 4-15. Dynamic stretch (start and finish position of exercise).

FIGURE 4-16. Dynamic stretch (position at full stretch). Laterally flex trunk at slow speed and return. Repeat (5-10 reps).

51

52

4. Stretching the Major Muscle Groups of the Trunk and Neck

Exercise 13-Trunk Rotators (3S Method) 4-17. Muscles to be stretched (iliocostalis lumborum, quadratus lumborum, internal oblique with opposite external oblique, serratus posterior, and rotatores). FIGURE

4-18. 3S Trunk rotators stretch (position and initial phase of exercise). Subject is seated, trunk rotated. P is standing in front of S, with P's left hand on S's right shoulder, and P's right hand on S's left shoulder. FIGURE

C:.i:-

ft L\.,j "

,', .,

I

.

, ",'-'~:

.;' :., .. . r','_ ~

4-19. 3S trunk rotators (position and middle isometric phase of exercise). Subject attempts to rotate trunk back to neutral position. P resists this effort, causing an isometric contraction. FIGURE

4-20. 3S trunk rotators stretch (position and end phase of exercise). After the 4-second build-up and a 6second submaximal isometric contraction, S relaxes for 2 seconds, then rotates his/her trunk for 3 seconds. P assists with light pressure. The trunk rotators are in the new lengthened position. Repeat the procedure 3 times from the new lengthened positions. FIGURE

Flexibility: A Concise Guide

Exercise 13-Trunk Rotators (Alternative Methods) FIGURE 4-21. Yoga stretch. Assume the position depicted. Perform a series of slow inhalations/exhalations, stretching further with each exhalation (30+ seconds).

FIGURE 4-22. Slow/static stretch (position of exercise). S is sitting, maintaining ideal position throughout the exercise. S, in a slow and smooth motion, rotates (direction of arrow) to one side, with arms crossed at chest. The movement continues as far as possible (pain free). S holds end position for 30+ seconds. S returns to initial position, and repeats the procedure to the opposite side. A total of 3 stretches per side are performed. .

..

':'>".: '..': ~ ~.~

- :' ';'

:,',;,:',",6"'",'' '

"." .".' ~,- r

"-

FIGURE 4-23. Dynamic stretch (start and finish position of exercise). Seated with arms crossed, as shown.

FIGURE 4-24. Dynamic stretch (position at full stretch). Rotate the trunk at the desired speed to end range and return. Repeat (5-10 reps) in both directions.

."

l"--

~~

53

54

4. Stretching the Major Muscle Groups of the Trunk and Neck

Exercise 14-Neck Quadrant (Range-of-Motion Method) 4-25. Muscles to be stretched (sternocleidomastoid, scalenes, splenius capitus, splenius cervicus, and upper trapezius). These movements should be performed as a slow, gentle complete range protocol. 3S or rapid ballistic are not recommended. These movements are not recommended for individuals with suspected compromised joint structures, vascular or neural conditions, or for the elderly.

FIGURE

4-26. Neck quadrant. S begins by slowly laterally flexing the neck to one side (toward the shoulder), but maintaining ideal neck posture. S continues to the point of end-range (no pain). Repeat for the opposite side. FIGURE

4-27. Neck quadrant. S slowly and carefully flexes (A) head and neck to end-range (no pain), then slowly hyperextends head and neck (B).

FIGURE

4-28. Neck quadrant (range of motion) exercise (position of third phase of exercise). S rotates to the opposite side to the end-range (no pain). S reverses motion to rotate in the opposite direction. Repeat the movements 3 times in each direction. FIGURE

5 Advanced 3S Stretching Exercises for Figure Skaters, Gymnasts, Divers, and Dancers

This chapter focuses on advanced stretching exercises for individuals wishing to achieve a high level of flexibility in the region of the hips, particularly figures skaters, gymnasts, divers, and dancers. Appropriate advanced 3S exercises will be presented.

From: Musculoskeletal Medicine: Flexibility: A Concise Guide to Conditioning, Performance Enhancement, Injury Prevention, and Rehabilitation By L.E. Holt, T.W. Pelham, and J. Holt © Humana Press Inc.. Totowa. NJ

55

56

5. Advanced 3S Stretching Exercises for Figure Skaters, Gymnasts

Exercise IS-Hip Adductors (Advanced)

", (i) •

.

'

-

..:','

I..' \

~

I ,

'"."" .~

.

;."

.

f'

FIGURE 5-1. Muscles to be stretched (adductor longus, adductor brevis, adductor magnus, and gracilis). It should be remembered that isometric contraction of 60% maximum voluntary isometric contractions (MVIC) or greater will maintain the isometric strength capabilities of the muscle group being stretched (agonist).

FIGURE 5-2. 3S hip adductors stretch (position and initial phase of exercise). S is standing on one foot, one hand on chair, exercise leg raised (abducted) as far as possible (pain free), with knee straight. P is standing to the side, both hands holding the exercise leg at the ankle.

FIGURE 5-3. 3S hip adductors stretch (position and middle isometric phase of exercise). S attempts to pull his/her leg toward the floor, keeping knee straight. P resists. FIGURE 5-4. 3S hip adductors stretch (position and end phase of exercise). After the 4-second build-up and a 6second submaximal isometric contraction, S relaxes for 2 seconds, then lifts leg toward ceiling for 3 seconds. P assists with light pressure. The hip adductors are in the new lengthened position. Repeat the procedure 3 times from the new lengthened positions.

Flexibility: A Concise Guide

Exercise 16-Hip Extensors (in Flexion) FIGURE 5-5. Muscles to be stretched (biceps femoris, semimembranosus, semitendinosus, gluteus maximus).

FIGURE 5-6. 3S hip extensors stretch (position and initial phase of exercise). S is standing on one foot, both hands on chair, with back relatively straight, and exercise leg straight and raised as high as possible (pain free). P is standing in front of S, holding the exercise leg at the ankle with both hands.

FIGURE 5-7. 3S hip extensors (position and middle isometric phase of exercise). S attempts to push the exercise leg to the floor, keeping the knee straight. P resists.

FIGURE 5-8. 3S hip extensors stretch (position and end phase of exercise). After the 4-second build-up and a 6second submaximal isometric contraction, S relaxes for 2 seconds, then lifts leg toward ceiling for 3 seconds. P assists with light pressure. The hip extensors are in the new lengthened position. Repeat the procedure 3 times from the new lengthened positions.

57

58

5. Advanced 3S Stretching Exercises for Figure Skaters, Gymnasts

Exercise 17-Split (Adductor-Extensor) 5-9. Muscles to be stretched (hip adductors/extensors).

FiGURE

FIGURE 5-10. 3S split adductor/extensor stretch (position and initial phase of exercise). S assumes a stretched position, supporting his/her weight on a soft mat with both legs and arms.

5-11. 3S split adductor/extensor (position and middle isometric phase of exercise). S attempts to raise his/ her body by pushing down with both feet against the floor. FIGURE

FIGURE 5-12. 3S split adductor/extensor stretch (position and end phase of exercise). After the 4-second build-up and a 6-second submaximal isometric contraction, S relaxes for 2 seconds, then allows gravity to lower his/her body to the new (pain free) stretched position for 3 seconds. The hip adductors and extensors in the split position are in the new lengthened position. Repeat the procedure 3 times from the new lengthened positions.

Flexibility: A Concise Guide

Exercise I8-Split (Adductor) FIGURE 5-13. Muscles to be stretched (hip adductors).

FIGURE 5-14. 3S split adductor stretch (position and initial phase of exercise). S assumes a stretched position, supporting his/her weight on a soft mat with both legs and arms.

FIGURE 5-15. 3S split (adductor) (position and middle isometric phase of exercise). S attempts to raise his/her body by pushing down with both feet against the floor. FIGURE 5-16. 3S Split (adductor) stretch (position and end phase of exercise). After the 4-second build-up and a 6second submaximal isometric contraction, S relaxes for 2 seconds, then allows gravity to lower his/her to the new (pain free) stretched position for 3 seconds. The hip adductors in the split position are in the new lengthened position. Repeat the procedure 3 times from the new lengthened positions.

59

6 Sports, Fitness, and Dance Applications

A prerequisite for effective and efficient movement is an adequate level of flexibility. From the activities of daily living to elite athletic and artistic performance, individuals must possess the necessary elasticity of soft tissues to accomplish the tasks they perform. Not everyone needs a daily flexibility program. However, if an individual participates in an activity in which added flexibility is desirable, or maintaining present levels is necessary, then it is advisable to include a stretching program in daily activities. For those who choose to stretch, there are many possible benefits (Table 6-1). In sport, fitness, and especially dance, stretching has several advantages. It is widely thought, among health professionals, coaches, athletes, and dancers, that those enthusiasts who regularly perform flexibility exercises are less likely to be injured while participating in their chosen activity and have less post-exertion muscular soreness. In addition, performing flexibility exercises before a sport or fitness routine helps to warm up the cardiovascular and musculoskeletal systems. While performing flexibility exercises, particularly 3S and dynamic stretches, there is an increased blood flow and nutrient supply to the active muscles, as well as an increase in lubrication to the joints. Flexibility training may also enhance proprioception, coordination, and motor control. In highly skilled activities involving large movement excursions, being flexible facilitates unrestricted and complete movement patterns and thereby enhances performance. One cannot hope to compete successfully in sports such as gymnastics, swimming, diving, and figure skating, or in the myriad forms of dance, without high levels of flexibility. Gleim and McHugh have suggested (and we agree) that the degree and kind of flexibility required for various physical activities will depend not only on the type of activity, but on the specific movements required of the particular participant in that activity, as well as (we further suggest) the From: Musculoskeletal Medicine: Flexibility: A Concise Guide to Conditioning, Performance Enhancement, injury Prevention, and Rehabilitation By L.E. Holt, T.W. Pelham, and J. Holt © Humana Press Inc.. Totowa, NJ 61

62

6. Sports, Fitness, and Dance Applications

TABLE

6-1. Possible benefits" of a regular flexibility program lJ

Enhancing the flexibility components of physical health as measured by standard tests Improving motor performance, particularly in many types of skilled movements in which elasticity of tissue and large range of motion is of importance Reducing the risk of soft tissue injury, reducing the severity of injury when it occurs Reducing the risk of back pain and injury by creating greater range of motion before soft tissues undergo excessive forces Reducing post-exertion muscular soreness Promoting neuromuscular relaxation, reducing muscular tension Reducing anxiety and mental stress (particularly with yoga) Enhancing posture Reducing symptoms (pain) in severe cases of menstruation (dysmenorrhea) "Many possible benefits listed have not been substantiated with sound, repeated research. "Stretching at inappropriate times, such as just after waking, may exacerbate an existing condition or cause injury.

participant's style of engagement (think about flexibility requirements for hockey generally, for goaltenders specifically, and, finally, for goaltenders of different styles ).1 In this chapter, we will explore why what might be called the principle of specificity is the fundamental training rule governing flexibility development for sport and dance. It will be seen that training effects will be maximized when there is a correct match of the movement patterns of major muscle groups as used in a particular sport with the appropriate flexibility program (some of the material presented here complements our discussion in Chapters 7 and 8). Athletes and dancers have been encouraged to stretch before and after training and competition. 2 Most coaches and dance instructors have advocated stretching as part of each performer's warm-up and cool-down. However, few coaches are aware of the literature that supports the specific benefits of proper flexibility training on actual performance. This stems from the fact that there are relatively few scientific studies available and they exist primarily in academic journals. With this in mind, we present a summary of the potential benefits of a sound flexibility program as applied to significant performance parameters of selected sports and artistic endeavors (Table 6-2). Leighton was one of the first to identify specific flexibility characteristics among elite athletes. 3 Since that time, joint-specific flexibility patterns of participants in specific sports and positions within a sport have been found to be related to performance outcomes. In sports in which required movements patterns dictate performance (such as diving, gymnastics, and figure skating), joint-specific flexibility is critical. In events such as high jumping and tumbling, a high level of trunk (spine) and hip flexibility is required to maximize performance. Generating power through large joint displacements is important in throwing events. Baseball pitchers and cricket bowlers, as well as discus

Flexibility: A Concise Guide

63

TABLE 6-2. Potential benefits of flexibility training" on performance in selected sports and artistic activities"

Sports with similar physiological, kinesioperceptual and psychological components

Important parameters

Performance responses

Artistic sports and activities (figure skating. gymnastics. diving. dance) I. Technique (skills)

Augment

2. Neuromuscular functions

Augment

3. Prevent soft tissue injury

Augment

Combative sports (boxing, wrestling, judo, karate, fencing) I. Technique (skills)

Augment

2. Prevent soft tissue injury

Augment

Stick and ball sports (baseball, softball. golf, racquet sports) I. Technique (skills)

Augment

2. Neuromuscular functions

Augment

3. Prevent soft tissue injury

Augment

Middle- and long-distance events (2 minutes or longer; running. swimming, cycling. rowing. canoeing) I. Technique (skills)

Augment

2. Prevent soft tissue injury

Augment

Team sports (basketball. soccer, ice and field hockey. volleyball. rugby) I. Technique (skills)

Augment

2. Prevent soft tissue injury

Augment

Short burst events (10 seconds or less; sprinting. throwing field events [shot put. discus. hammer. etc.]. football) I. Technique (skills)

Augment

2. Explosive power 3. Prevent soft tissue injury

Augment Augment

Target sports (curling. archery) I. Technique (skills)

Augment

2. Neuromuscular functions

Augment

3. Prevent soft tissue injury

Augment

I. Prevent soft tissue injury

Augment

Bodybuilding and prodigious lifting

"These are suggested benefits that need validating research. "Flexibility training will not affect weight control, anaerobic power. immune system capacity. aerobic capacity. or hypertrophy.

64

6. Sports, Fitness, and Dance Applications

and javelin throwers, require a large range of motion of the shoulder girdle and joint to develop the torque needed to propel the object at high velocity. In fact, top performance in many sports requires the ability to rapidly develop concentric torque after dynamic eccentric movements. One study found a positive relationship between tissue elasticity and the storage and release of elastic energy.4 The stiffer the tissue, the less recoil energy. In a follow-up study, it was found that, after the incorporation of flexibility exercises into their regular training program, experienced power lifters saw, on average, not only a 13% improvement in flexibility, but a 5.4% increase in maximum bench press. 5 The researchers attributed the improvements to changes in the elasticity of the musculotendinous unit, which aids in the storage and release of elastic (potential) energy during the stretch-shorten cycle. In a related study, it was found that 8 weeks of stretching yielded improvements in knee isokinetic torque production. 6 Increases in muscle cross-sectional area caused by strength training has been attributed in part to an increase in the concentration of connective tissue, specifically collagen. The increase in biosynthesis of collagen is accompanied by an increase in cross-bridging. The muscle-tendon complex will become stiffer. Although this will allow for an increase in the efficiency of the transmission of force (power production) in the muscle-tendon complex at low velocities, at high velocities, power will be decreased. In sports in which performance is measured by a blend of mechanics and aesthetics (such as gymnastics, figure skating, diving, and synchronized swimming), a high level of flexibility is invariably required. 7 Similarly, in Tae Kwon Do, experienced practitioners were found to have higher levels of flexibility than novice participants. s Indeed, in sports that require precision during short bursts of explosive activity (such as golf and squash), stretching before training and competition may prove beneficiaL 9 In all sports and kinetic artistic endeavors, peak performance is primarily based on the precise application of a learned set of skills. Among 84% of trainers and coaches of elite university sports in the United States, it is thought that flexibility is important for improving sport performance. to As well, most think that flexibility is important in injury prevention and recovery.11 This relationship has been demonstrated in ice hockey with young players at a skill development camp.12 Other important factors in both sports and dance are neuromuscular control and optimal psychological arousal. Although the popular literature suggests that flexibility training is a positive influence on mood,13 the authors could not find highly regarded scientific studies supporting this, although a recent study found that regular stretching was found to be beneficial to the heart rate of healthy male athletes, and possibly related to positive changes in vagal and sympathetic controL I4 Of all methods of stretching, it is believed by many experts that yoga is the best approach for positive mood and relaxation.

Flexibility: A Concise Guide

65

As we know, flexibility is an important component of general and sportspecific fitness. Flexibility exercises are designed to increase tissue elasticity, increase range of motion, enhance performance, and reduce the chance, severity, and frequency of injuries. Experimentation has shown a strong correlation between range of motion and quality of performance,15 especially with respect to sports such as swimming. 16 Hume et al. found a positive and significant correlation between success in rhythmic gymnastics and a composite score on flexibility tests. 17 Cohen et aI., using video analysis, velocity testing, and goniometric measurements, found that dominant shoulder and wrist flexibility were associated with increases in tennis-serve velocity in elite players. 18 Generally speaking, sport-specific levels of flexibility have positive effects on performance in virtually all sports. 19 Some hold that increased flexibility leads to better conditioning, and that it is conditioning that enhances performance. 2o In fact, in two studies, stretching muscles before activity facilitated contraction and improved force outpUt. 21 Both studies found that fast stretching before a ballistic propulsive movement increases the effect. This is seen in virtually all ballistic skills. Stretch the prime movers, thereby storing elastic energy, and subsequently contract these muscles concentrically in synchronization with the release of the stored elastic energy. The resulting effort is more powerful. Indeed, the type and amount of training influences flexibility. It is clear that there is often a loss of flexibility after hypertrophic strength training. As well, it would seem that a properly designed flexibility program may counteract the detrimental effects of excessive strength training without compromising the objectives of the strength training. If one works 3S with increasing isometric effort, then one can either increase isometric force or maintain the strength at new end range. 22 3S with a healthy athlete using strong isometrics can be an adjunct to performance by maintaining power at a greater range of motion. Although flexibility training seems to have negligible, if any, negative effects on other fitness parameters, including power activities such as vertical jump,23 athletes and coaches with an insufficient understanding of basic physiological and anatomic principles will often make gross errors in training, leading to poor performances and, often, injuries. There is little uniformity of flexibility training programs, and the testing procedures used are often standard laboratory tests that have little application to sport. Compared with other fitness parameters, such as aerobic capacity, strength, and neuromuscular endurance, shockingly little attention has been given either in experimentation or practice to flexibility in the sport science environment. Appendix E contains a basic foundational set of stretching exercises arranged by activity. Clear, precise instructions and figures for these exercises have been presented in Chapters 1 to 5.

66

6. Sports, Fitness, and Dance Applications

Errors in training often lead to injuries in many athletes. Before prescribing any exercise protocol, a comprehensive biomechanical/physiological assessment of the individual should be conducted. It is important to identify the underlying limitations and deficits ofthe individual. All flexibility training should follow scientific, evidence-based principles, keeping in mind the expressed goals of the individual. Standardized musculoskeletal screenings and evaluations are not sufficient, particularly for the young, older, or injured athlete.

References 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23.

Gleim and McHugh (1997). Holt (1974). Leighton (1957). Wilson et al. (1991b). Wilson et al. (1992). Wilson et al. (1992). Soares de Araujo (2004), Knudson et al. (2000). Toskovic et al. (2004). Somes de Amuja (2004). Market Research Associates Ltd. (1994). Market Research Associates Ltd. (1994). Pelham and Hoyle (1992). Alter (1990). Mueck-Weymann et al. (2004). Dubuc and Bohannon (1985). Prichard (1987). Hume et al. (1993). Cohen et al. (1994). Pelham (1994b). Shellock and Prentice (1985). Cavagna et al. (1968), Burke et al. (1999). Holt and Smith (1983). Little and Williams (2006), Unick et al. (2005), Woolstenhulme et al. (2006).

II Theoretical Considerations

7 Flexibility and Exercise

Stretching exercises have long been advocated as a means of improving performance, reducing the risk of injury, and facilitating rehabilitation after injury. However, there is conflicting evidence in the literature regarding the possible benefits of flexibility training. In sport, flexibility training programs are largely based on a coach's or trainer's opinion, which often derives from personal experience, sometimes in conjunction with a limited or uncritical reading of the literature. The available literature, furthermore, varies widely in quality, from tightly controlled, well-designed experiments to experiments that are poorly constructed and draw unwarranted conclusions. Many published articles violate accepted research standards yet have nonetheless influenced practitioners to form a number of erroneous beliefs. The purpose of this chapter is to provide an overview of the available research literature, focusing on more or less generally accepted findings and less controversial claims. In Chapter 8, we will then explore some of the more controversial literature, our purpose being to explore the myths that have infiltrated our understanding of flexibility, exposing the lack of solid foundation to hold them up.

Factors That Affect Flexibility There are a number of factors that influence an individual's level of flexibility. Some of these factors are modifiable, subject to voluntary control to some (somewhat modifiable) or a large (modifiable) extent, others are not (Table 7-1).

Age Although there is a great deal of variance among individuals,l a number of studies have shown that flexibility decreases with age? Young children are From: Musculoskeletal Medicine: Flexibility: A Concise Guide to Conditioning, Performance Enhancement, Injury Prevention, and Rehabilitation By L.E. Holt, T.W. Pelham, and J. Holt © Humana Press Inc.. Totowa, NJ

69

70

7. Flexibility and Exercise TABLE

7-1. Factors that influence flexibility

Nonmodifiable

Somewhat modifiable

Modifiable

Age Sex Time of day

Anatomic constraints Disease Injury Posture Temperature

Exercise

generally very flexible. 3 With the onset of adolescence, however, there tends to be a gradual decline in flexibility, continuing throughout the lifespan. 4 Arthritic conditions and a sedentary lifestyle during the aging process may be contributing factors. 5 A decrease in flexibility can be associated with a reduction in the performance of activities of daily living in the elderly.6 Although the elderly are often less flexible than they were earlier in life/ there is evidence that they are no less responsive to flexibility training than younger people. s These studies suggest that regular activities to maintain elasticity, or specific stretching programs, would be important for aging individuals.

Sex Sex is another factor that influences flexibility. Females are generally more flexible than males, especially in younger age groupS.9 Women also become more flexible during pregnancy.10 An increased concentration of the hormone relaxin has been cited as a key contributing factor to explain this increased flexibility. II It has been our experience that women achieve greater increases than men when both are placed on the same stretching program. We speculate that, on average, women have a larger percentage of elastin in their myofascia than their male counterparts.

Time of Day For most people, flexibility varies during the course of a day. People are usually stiffer in the morning when they first wake up, becoming more flexible as activity increases during the day. Research has shown that individuals have greater flexibility of the cervical spine during the late afternoon and evening hours. 12 Most noticeably, the lower lumbar spine shows demonstrable improvements in flexibility as the daytime hours progress, and is least flexible during hours of sleep.!3 Prolonged activity or sedentary periods, as well as fatigue, can also be associated with decreased flexibility. 14

Flexibility: A Concise Guide

71

Anatomic Constraints There are constraints on the amount of flexibility enhancement that an individual may achieve. Resistive properties, both passive and active, influence the amount of elasticity that is possible within any given tissue. These neurogenic and myogenic constraints are interactive under active resistance. l ) Muscle spindles, golgi tendon organs (GTOs), and less elastic soft tissues all playa role in resisting extreme range of motion. In addition, anatomic constraints, such as each joint's configuration, its capsule, and its ligaments, may delimit possible range of motion. For example, ball and socket joints of the hip and shoulder afford a greater degree of movement, in more directions, than the uniaxial or biaxial joints. Friction, skin, soft tissue contact, and subcutaneous constraints also influence the amount of flexibility that can be achieved at some joints. I!> Large, hypertrophied muscles and excess fatty tissue may limit range of motion because of the soft tissue contact of adjacent body segments. However, the major limitation on both static and dynamic flexibility in many locations is the tightness of soft tissue structures. In an early animal study, Johns and Wright studied the wrist joint of the cat. 17 Their selection was based on the fact that the cat's wrist is of similar size and function to the metacarpophalangeal joint of humans. They determined the relative contribution of soft tissues to the total resistance encountered by the joint during midrange movement: • • • •

Joint capsule: 47% Muscle and its fascia: 41 % Tendons: 10% Skin: 2%

They concluded by suggesting that this relative contribution to total resistance is uniform throughout the body. However. this is obviously a hasty generalization. Restrictions in humans (and in cats, for that matter) are clearly different at different selected sites. Joint capsules, tendons, and ligaments consist primarily of collagen, a non-elastic connective tissue. The muscle and enveloping fascia are composed of tissues that are more elastic and, therefore, are more modifiable. Reducing resistance to movement (stiffness) in muscle and fascia results in increased flexibility at or about joints where such tissues create the greatest resistance. Within such constraints, and according to the above principles, increases in flexibility can be achieved in the soft tissues under stretch, including fascia, muscles, skin, and (more limitedly) tendons. IK Deformations in tissue shape or size may be either elastic (relatively temporary) or plastic (relatively permanent), and take place under a variety of conditions. 19 Some

72

7. Flexibility and Exercise

researchers attribute elastic deformation to the tissues' collagenous glycosaminoglycan (GAG), which, when in short supply, limits range of motion augmentation even when tissues are subjected to a thorough stretching regimen. This is why individuals respond differently to the same stretching program, and variations even occur within the same individual. 20

Disease Some conditions, such as arthritis, involve decreased flexibility, either because the tissues have lost some of their elasticity, or because pain prevents the elasticity from being used to full capacity. For individuals with arthritic conditions, therapists have recommended morning and evening stretching as a means of decreasing morning stiffness. 21 However, stretching the spine in the morning requires caution, because intervertebral disc hyperhydration is present and injuries could result. 22 Limited joint motion (hypomobility) has been found in individuals with diabetes mellitus. 23 Although the exact reason for such diminished range of motion is not clearly understood, research has found distinct differences in collagen profiles between those with diabetes mellitus and those without. Individuals with diabetes have a larger number of crossbridges per unit area and a higher concentration of glycosylation than individuals without the condition. 24 Hemophilia is another condition associated with hypomobility, as well as with underlying degenerative joint changes. 25 Unlike nonmodifiable factors, such as age, sex, and time of day, many chronic diseases, such as arthritis and diabetes, are somewhat modifiable, or at least manageable after onset. Indeed, appropriate management of chronic disease requires maintaining an appreciable level of functionality, that is, maintaining at least (among other things) an adequate level of flexibility.

Injury A relationship between flexibility and the incidence of injury has been established. Less flexible athletes and military recruits undergoing basic training with low or excessive levels of joint motion were found to have a higher incidence of injury.26 Restricted ankle dorsiflexion has been identified as one of the risk factors in the development of musculoskeletal overuse injuries, particularly Achilles tendinopathy (tendonitis ).27 Several studies have shown that stretching is an effective strategy to reduce the risk of injury associated with various physical activities. Inflexibility has been identified as a risk factor for running injuries, which suggests that a lower limb flexibility routine should be incorporated into running programs. 28 The high incidence of knee injury, particularly trauma to the anterior cruciate ligament, has been associated with flexibility

Flexibility: A Concise Guide

73

imbalance between muscle groups of the lower limb in female athletes; 29 proper stretching programs have been recommended to correct such imbalances. Stretching has also been advocated as a preventive tool for high-risk regions for injury (shoulders and back) in young tennis players. 3o Finally, stretching has been recommended as part of the warm-up and cool-down routine for postmenopausal women involved in general fitness programs. 31 Supporting the view that stretching is an effective means of injury prevention, Wilson, Wood, and Elliott have proposed a mechanism of injury to the musculotendinous unit. 32 They suggest that a stiff musculotendinous unit may not have a sufficient level of elasticity to absorb applied forces, particularly during eccentric movements. A more elastic unit can buffer more effectively the mechanical shock of rapidly developing torque, particularly during dynamic eccentric movements. Muscle elasticity involves the storage of energy and, as a result, has a mechanical influence on force output. More precisely, during a muscular contraction, the series elastic component (tendons) will undergo restricted lengthening, followed by the transmission of force through the tendons to the bony attachments. The parallel elastic component is not involved in developing tension, but its proximity to the contractile components involve it in the transmission of forces. During vigorous eccentric to concentric contractions, both elastic components absorb the forces, thereby protecting the muscle-tendon complex from injury. There is a strong positive correlation between flexibility and elasticity in the musculotendinous unit. Indeed, this relationship has a direct impact on the damping effect on the unit during eccentric activities. As stated above, the ability to absorb shock force will reduce the probability of muscular tearing. A properly managed stretching program has injury prevention qualities.

Posture It has been suggested that posture can influence one's level of flexibilityY

For example, limited hip and trunk flexion was found to be associated with poor postural spinal alignment. 34 A seated flexed posture has been shown to produce large tensile forces on the lower lumbar region, which is thought to be a source of lower back pain. 35 Maintaining awkward positions for long periods of time, and failing to maintain correct alignment of the spine, may lead to significant flexibility loss.36 A kyphotic thoracic spine, with the head excessively forward, together with bilateral shoulder girdle abduction, has often been associated with diminished flexibility of the pectoral musculature, particularly the pectoralis minor. This kind of slouching posture can have major repercussions for shoulder range of motion 37 as well as ribcage mobility (effective breathing).

74

7. Flexibility and Exercise

Temperature Temperature also influences flexibility. Wright and Johns reported that warming a human metacarpophalangeal joint to 45°C resulted in an increase in extension range of motion of 20%, whereas cooling the hand and wrist joints to 18°C resulted in a 10 to 20% percent decrease in range of motion. 38 In both laboratory and clinical settings, the application of heat results in increased flexibility.39 This is accounted for by decreases in collagen viscosity, allowing for a greater range of motion. 40 A warm-up routine before stretching is probably the most popular way to raise tissue temperature and enhance the effects of a stretching regimen. However, the way in which temperature changes are brought about is significant. Certain warm-up activities will result in increased elasticity, but not others. For instance, riding a bike for too long, while raising the internal temperature of the muscle, results in a net loss of flexibility.41 This means that increased heat is likely to increase flexibility, all else being equal, whereas certain activities, particularly those that involve shortening the tissues, may counteract such effects. We recommend avoiding in any prestretch warm-up routine any activity that involves the kind of repetitive movements at less than full range of motion that can lead to tissue shortening. Thermal modalities are commonly used to enhance the effects of stretching. In one study, a 7-minute treatment of thermal ultrasound before stretching significantly increased dorsiflexion in males and females with ankle flexibility deficits. 42 It has been suggested that a thermal ultrasound treatment must raise tissue temperature at least 5°C for stretching to be enhanced. 43 On the other hand, thermal diathermy was found to have no effect on enhancing hamstring flexibility.44 Others have found that cold facilitates tendon extensibility, and that cryotherapy, in conjunction with a stretching regimen, is more effective than the stretching regimen alone. 45 Hamstring flexibility was found to be greater in male collegiate baseball players after a 20-minute stretching routine combined with the application of ice than with the same stretching routine and the application of heat, or stretching alone. 46 Finally, in a study involving 3S stretching plus thermal manipulation (10 minutes submersion in either hot or cold water), hamstring flexibility improved in all members of each of the three experimental groups (stretching only, cold and stretch, heat and stretch) after machine-aided 3S. 47 However, although hamstring flexibility improved greatly in all three groups, no differences were found between the three experimental groups. We hypothesize that temperature changes can enhance the effects of a stretching routine but only when the routine by itself would yield less than optimal results.

Flexibility: A Concise Guide

75

Exercise The degree and type of exercise affects f1exibility.~K It is well documented that inactive persons tend to be less flexible than active persons and that exercise generally increases flexibility. Indeed. it has been suggested that regular quality activity, whether a physical education program or activity in general, is related to f1exibility.49 Active people tend to be more flexible than those who are sedentary, and regular flexibility exercises for active individuals will increase their level of f1exibility.'o Some activities are particularly well suited to increasing flexibility. A positive relationship has been found between total hours of either swimming or gymnastics and the flexibility of selected joint movements of the lower extremity,'1 Generally speaking. not only swimming and gymnastics. but wrestling. dancing. and, of course, stretching. all increase f1exibility.'2 However. not all physical activities have the same effect on f1exibility.'.1 Research has consistently shown that various different types of activities and sports can have negative effects of flexibility. It is false to generalize that all exercise increases flexibility. Activities that involve less than complete range of motion, such as cycling. jogging and restricted range resistance exercises. will result in soft tissue shortening. Such training has a negative influence on flexibility."· Cycling and running. in particular. reduce elasticity in the hip flexors and other musculature." Long-distance joggers and runners tend to have tighter hamstrings than normal individuals. with very restricted hip flexion when the knee is extended.'!> The repetitive impact forces of running. combined with inadequate flexibility. are important factors associated with running injuries.'7 Stretching not only increases the biomechanical efficiency of running. it significantly decreases the likelihood of running-related injuries.'s In our experience, cyclists and others whose predominant mode of conditioning is cycling (regular or stationary) are the least flexible of all active people. particularly in the lower body (iliopsoas. iliotibial band. hamstrings, and calf). This is well illustrated by iliotibial band syndrome. a common overuse injury in cyclists, for which the usual recommended treatment is stretching.,9 It has been found that subjects. after being fully stretched. lost range of motion after calisthenics. walking. and cycling (at a continuous heart rate of 105-115 beats per minute, and tested at both 15 and 30 minutes after exercise), as they also did when sitting for the same time period of time. ho The same study determined that a properly performed 3S flexibility program, after the aforementioned activities or period of inactivity, restored optimal range of motion to the tissues of these regions. It seems that maintaining a fully stretched condition will be activity dependent. Another important factor affecting flexibility is resistance training. Light to moderate. full range, many reps resistance training does not negatively

76

7. Flexibility and Exercise

affect flexibility. However, heavy resistance training, with few reps and attenuated excursions, reduces range of motion, either through earlier soft tissue contact of hypertrophied muscle, contractures developed through less than full range of motion reps, or both. An extensive strength-training program for elite female soccer players resulted in reductions in range of motion at the hip.6l This was plausibly caused by the training effect on the musculature surrounding the hip increasing the stiffness of the trained tissue and, thereby, reducing both static and dynamic flexibility. There is significantly greater muscle damage in "stiff" versus "compliant" hamstrings with eccentric exercise. 62 Stretching before isokinetic testing has been shown to increase hamstring performance. 63 Although some still believe that isotonic strength training has no effect on flexibility,64 others believe that this form of conditioning in fact decreases flexibility.6s Individuals involved in sports that require repetitive explosive rotary movements of the hips, such as ice hockey, figure skating, most racquet sports, golf, martial arts, and dance, often develop limited hip rotational flexibility.66 Inadequate flexibility of the hips can have a significant effect on lumbopelvic posture. An abnormal posture of the lower back can increase the risk of lower back injury, particularly in individuals who play contact sports. In such cases, a stretching program for the outward (lateral) and inward (medial) hip rotators is recommended. 67 Disuse due to immobilization produces contracture and shortening of connective tissue, which restricts mobility. Using joints and muscles repeatedly in the same way, or maintaining habitual body postures, can restrict range of motion owing to the tightening and shortening of the myofascial tissues that occurs. People whose jobs require them to sit for long periods of time often complain of lower back pain caused by taut hamstrings and lower back muscles. 6s Long periods of sitting can also produce limited range of motion in the hip flexors. 69 Finally, stretching is not a typical component of the warm-up in most power and strength sports, particularly weightlifting, even though these activities usually require a high degree of flexibility.70

Ways to Improve Flexibility Massage, warm-up, and stretching are three basic techniques used to increase flexibility. Massage is a popular technique advocated to relax musculature and increase pain free movement. 7! Although the overall effects of such techniques may be positive perceptually (the individual feels better), the effects of massage on flexibility are comparably minimal and short lived. A warm-up session is recommended, and commonly used before training or competition. 72 It has been long held that warm-up increases tissue temperature and, in turn, f1exibility.73 But neither massage nor warm-up is as

Flexibility: A Concise Guide

77

efficient as a proper stretching regimen in increasing flexibility, and, as we shall see, there are significant differences in the effects of different stretching methods. 74

Different Stretching Methods Stretching is the best way to increase flexibility. The three basic, classic approaches are slow/static, dynamic (ranging from controlled to ballistic), and the many forms of proprioceptive neuromuscular facilitation (PNF). Slow/static stretching involves the slow, gradual lengthening of the muscle group (agonist) at or about a joint or set of joints, usually by a slow concentric contraction of its antagonist, until the point at which further lengthening is prevented by the agonist tissue's own tension?' Dynamic stretching involves subjecting the muscle group at or about a joint or set of joints to a sequence of continuous full range excursions ranging from relatively slow to terse and violent ballistic movements caused by rapid alternating concentric contractions of both agonists and antagonists. 76 PNF and its many variations are all based on Kabat's original theories,n which, in turn, were based on principles derived from the work of Charles Sherrington. 7H The most effective variation of PNF is called reversal of antagonists. This technique, as applied in the 3S method, involves a series of less than maximal isometric contractions of the agonist muscles in a prelengthened state (to set up the stretch), followed by concentric contractions of the antagonist muscle group (to lengthen the agonist) in conjunction with light pressure from a partner when needed (it may surprise some readers to know that some forms of partner-assisted stretching have been around for longer than 2000 years 7Y ).xo

When and How to Stretch Flexibility is necessary to perform many different movements in sport and in everyday life, on the job and off. Because flexibility is an important component of fitness, flexibility training can and should be emphasized to varying degrees depending on the individual's needs and objectives at that point in time. For a gymnast, figure skater, diver, or dancer, for instance, flexibility training obviously has to playa major role in the conditioning program. We recommend using 3S whenever possible, as the foundation of a stretching program. However, in cases in which dramatic increases in range of motion are not needed, or as time restrictions or lack of an available partner may necessitate, as in many fitness and recreational programs, slow or low-speed dynamic stretching may be helpful just before and after

78

7. Flexibility and Exercise

activity. Because many sports and recreational activities actually diminish flexibility, despite the increased tissue temperature, it is recommended that a second bout of stretching be performed at the end of each workout to reset the soft tissues to their optimum level. As discussed earlier in the text, the 3S technique has been used extensively by athletes and dancers to prevent injury and to create dramatic increases in specific movements to enhance performance mechanics or aesthetics. It has worked well in many conditioning programs for a variety of competitive sports and dance specialties. 3S training has also been applied to rehabilitation (Chapter 9) as a way of promoting tissue recovery, or as helping to improve the patient's state of physical fitness and general well-being. This would apply to any patient, not just athletes engaged in sport. For those who need to enhance their flexibility, or want to maintain high levels of it, we recommend that 3S training be performed before and after activity, and on off days, at least twice daily, to increase and maintain tissue elasticity, and the consequent range of motion. Other objectives for which 3S training is indicated include: • Alleviating muscle tension • Facilitating healing by increasing blood flow • Decreasing muscle pain (by reducing vasoconstriction, which, in turn, reduces trigger point activity and, thereby, reduces pain)

When Not to Stretch Not everyone needs to stretch, lift weights, or do other forms of exercise each and every day. If tissue elasticity is sufficient for one's daily activities, stretching exercises may not be required. There are specific times and circumstances where stretching should not be performed. For instance, many back injuries occur when exercises are performed immediately after waking up in the morning. The spine, especially the lumbar discs and surrounding tissues, are particularly vulnerable at this time. Contraindications and precautions to any stretching protocol include: • Reduced/impaired joint receptor and pain sensations (analgesic medication) • Joint instability (hypermobility) • Conditions, as indicated by a health professional, in which mobilization of tissue is contraindicated (e.g., cancer, thrombus) • Significant soft tissue injury • Surgical supportive devices (nails, wire, screws, pins, plates) in an area to be stretched • High-risk osteochondritis dissecans situations, as indicated by a health professional

Flexibility: A Concise Guide

79

• Some types and conditions of fractures, particularly in the early stages of healing • Genetic conditions causing excessive laxity of soft tissues • When stretching or tension in tissue elicits pain • Just after waking up, particularly the vertebral column

Training Principles There are three principles of training that explain tissue adaptation. The principle of overload requires the tissues exercised to be "taxed toward their present capacity to respond."s, The principle of specificity requires adaptation both at the cellular and gross anatomic levels to those structural and functional elements that are taxed toward their present responsive capacity.s2 Many of the causal and conditional relationships between the biochemical, morphological, and biomechanical aspects of such adaptation have not, however, been found. s1 The third principle, the principle of retrogression, implies that adaptations beyond normal conditions will regress to pretraining status once training ceases. S4 Applying these principles to flexibility training suggests that the most effective technique will be that which: • • • •

Taxes the tissues toward their threshold of present responsive capacity Minimizes the risk of injury Causes functional and structural changes at the cellular level Is maintained to prolong and build on already achieved gains

Of the three basic stretching methods we have discussed, these principles favor PNF. Among the various derivatives of PNF, they favor 3S in particular.

Summary A number of factors affect flexibility, including age, sex, time of day (nonmodifiable), anatomic constraints, disease, injury, posture, temperature (somewhat modifiable), and exercise (modifiable). Various forms of muscle training (particularly strength training) influence flexibility, often negatively, and must be considered as influences to counteract in the design of any flexibility program. Massage, warm-up, and stretching are the hasic techniques used to increase flexibility. There are three basic types of stretching: slow/static, dynamic, and PNF. PNF is superior. However, there are several variations of PNF stretching, and research has found 3S is the superior PNF derivative. Stretching is recommended both before and after sport and exercise activity. Precautions must be taken by anyone wishing to engage in a

80

7. Flexibility and Exercise

stretching program. Training principles have been discussed and favor the use of 3S as the primary stretching protocol.

References 1. Knudson et al. (2000). 2. Clarke (1975), Corbin and Noble (1980), Gadde et al. (2006), Hubley-Kozey and Stanish (1982), Smith (1982), Hedrick (2000). 3. Knudson et al. (2000). 4. Clarke (1975), Corbin and Noble (1980). 5. Holland et al. (2002), Knudson et al. (2000). 6. American College of Sports Medicine (2000). 7. American College of Sports Medicine (2000), Knudson et al. (2000). 8. Chapman et al. (1972), Bell and Hoshizaki (1981), Germain and Blair (1983), Dummer et al. (1985), Hahn et al. (1999), Feland et al. (2001a), Feland et al. (2001b), Schramm et al. (2001), Tseng et al. (2007). 9. Kirchner and Glines (1952), Phillip et al. (1955), Hahn et al. (1999), Hedrick (2000), Knudson et al. (2000), Schramm et al. (2001). 10. Alter (1988), Dumas and Reid (1997). 11. Calguneri et al. (1982). 12. O'Driscoll and Tomenson (1982), cited by Soares de Araujo (2004). 13. Russell et al. (1992), cited by Soares de Araujo (2004). 14. Pelham and White (2003), Pelham et al. (2005). 15. Hutton (1992). 16. Hutton (1992). 17. Wright and Johns (1962). 18. Mathews et al. (1964). 19. Alter (1988). 20. Akeson et al. (1980), Donatelli and Owens-Burkhardt (1981), McDonough (1981). 21. Minor (2004). 22. McGill (2002). 23. Grgic et al. (1976), cited by Soares de Araujo (2004). 24. Campbell et al. (1985), cited by Soares de Araujo (2004). 25. Johnson and Babbitt (1985), cited by Soares de Araujo (2004). 26. Jonhagen et al. (1994), Hartig and Henderson (1999). 27. Kaufman et al. (1999). 28. Johnston et al. (2003). 29. Hewett et al. (2001). 30. Roetert et al. (2000), Kibler and Chandler (2003). 31. Asikainen et al. (2004). 32. Wilson et al. (1991a). 33. Hutchins (1965), Smith (1982), Ninos (2001), Beach et al. (2005). 34. Flint (1964), Pelham and White (2003). 35. Hedman and Fernie (1997). 36. Pelham and White (2003), Pelham et al. (2005). 37. Crawford and Jull (1993). 38. Wright and Johns (1961). 39. Sechrist and Still (1969), Hubley-Kozey and Stanish (1982), Lentell et al. (1992), Hedrick (2000), Funk et al. (2001), Sawyer et al. (2003).

Flexibility: A Concise Guide 40. 41. 42. 43. 44. 45. 46. 47. 48. 49. 50. 51. 52. 53. 54. 55. 56. 57. 58. 59. 60. 61. 62. 63. 64. 65. 66. 67. 68. 69. 70. 71. 72. 73. 74. 75. 76. 77. 7R. 79. 80. 81. 82. 83. 84.

81

Williford et al. (1986), Alter (1988), Sawyer et al. (2003). Culligan (1996). Knight et al. (2001). Draper and Ricard (1995). Draper et al. (2002). Lehmann et al. (1970), Cornelius and Jackson (1984). Brodowicz et al. (1996). Burke et al. (2001). Girouard and Hurley (1995). Holland (1968), Clarke (1975). Cureton (1941), McCue (1963), Hedrick (2000). Hahn et al. (1999). Bandy et al. (1997), Hahn et al. (1999), Spernoga et al. (2001). Culligan (1996), Gleim and McHugh (1997), Hahn et al. (1999). Gleim and McHugh (1997), Holt and Pelham (2001), Vad et al. (2003), Wang et al. (1993), Anderson (2000), Holt and Pelham (2001). Wang et al. (1993), Holt and Pelham (2001). Bach et al. (1985), Wang et al. (1993). Simoneau et al. (1997). Simoneau et al. (1997), Winton (2003). Holmes et al. (1993). Culligan (1996). Schmitt et al. (1998). McHugh et al. (1999). Worrell et al. (1994). Massey and Chaudet (1956), Girouard and Hurley (1995), Klinge et al. (1997). Pelham et al. (1999), Holt and Pelham (2001). Regan (2000), Ninos (2001). Regan (2000). Pelham and White (2003), Pelham et al. (2005). Pelham and White (2003), Pelham et al. (2005). Schilling and Stone (2000). Salzmann (1982), Crosman et al. (1984), Hernandez-Reif et al. (2003), Hilbert et al. (2003). American College of Sports Medicine (2000). Smith (1994), Reed (2005). Wiktorsson-Moller et al. (1983), Shellock and Prentice (1985). Alter (1988). McAtee and Charland (1999). Kabat (1958). McAtee and Chraland (1999). Evjenth and Hamberg (1988). Holt (1974). Enoka (1988). McCafferty and Horvath (1977), Zernicke and Loitz (1992). Zernicke and Loitz (1992). Thorstensson (1977).

8 Myths About Stretching

Although stretching traditionally has been viewed as a key component of sport and fitness conditioning, performance enhancement, injury prevention, and rehabilitation, there are many who currently believe it to be of limited practical value in any exercise or rehabilitation setting. Many myths regarding stretching and flexibility have been promulgated, and there is a growing confusion in the sport and exercise sciences, one that needs to be redressed. In this chapter, we expose the myths for what they are, defending a far more traditional, yet better justified perspective on the benefits of stretching.

Review of Reviews Much of the negative attitude toward stretching can be traced to several recent books and literature reviews published in academic journals and presented at professional symposia. We think that these critiques of stretching are flawed in several important respects. Before moving on to the specific myths themselves, however, it will be useful to identify some of the general problems endemic to many of the works we target. 1. Definition of terms. As we observed in the introduction, there is much confusion in the literature regarding the very meaning of the word "flexibility." Along with practitioners, writers and reviewers are not always clear regarding whether they are focusing on mobility, compliance, the reciprocal counterpart of stiffness, range of motion, static flexibility, or dynamic flexibility. If there is a lack of clear consensus on what flexibility is, then its applications will likely also be misunderstood. as is often the case.

From: Musculoskeletal Medicine: Flexibility: A Concise Guide 10 Conditioning, Performance Enhancement, Injury Prevention, and Rehabilitation By L.E. Holt, T.W. Pelham, and J. Holt © Humana Press Inc., Totowa, NJ 83

84

8. Myths About Stretching

2. Completeness. A good literature review involves a thorough analysis of the available materials. Three recent reviews have been woefully incomplete in their coverage. Reviews by Herbert and Gabriel, Shrier, and Nelson and Bandy, for example, have 30, 57, and 52 references, respectively, each excluding dozens of articles and many books on the subject.' Minimizing or excluding such pro-stretching material leads to an unbalanced literature review. The sample should at least be a representative one. An interesting case in point is the monograph Scientific Stretching for Sport (3S). With more than 4,000 copies sold internationally, this book was not mentioned in any of the reviews, nor were any of the authors' 20 published articles. 2 3. Hasty generalization. After a too-selective sampling of available materials, reviewers often base very sweeping generalizations on a few published studies (often two or three studies). Not only are the references limited in number, they are often accepted uncritically, despite being seriously flawed. 4. Sample quality. In most reviews, the quality of the referenced material is not addressed in any detailed or rigorous way. Surprisingly, in one recent review, although a quality assessment was performed, studies that rated poorly on the reviewer's own scale were included in the evidentiary mix on a par with the good studies, as though they had rated well. 3 5. Assumption of uniformity. Perhaps the most egregious mistake has been the acceptance of slow/static stretching as the "gold standard" of flexibility enhancement. The prevailing presumption seems to be either that the slow/static method provides the best stretch possible or that it serves to provide a good indication of the effects of all stretching techniques. The fact that different techniques and protocols have different effects is widely known, but then glossed over in the wake of sweeping statements regarding "stretching" and its effects generally.

A good review of the literature dealing with flexibility would approach sweeping generalizations very cautiously, particularly because there are so few well-controlled studies on which to base judgments, and, therefore, much confusion in the minds of researchers and practitioners alike. In what follows, we expose the prevailing myths regarding stretching for what they are.

Myth 1: Stretching Causes Injury Ian Shrier has argued that stretching before physical activity increases the likelihood of injury during the activity.4 He attempts to justify this claim in four different ways. 1) Shrier advocates the stretch tolerance hypothesis, according to which, stretching alters pain thresholds, delaying the onset of

Flexibility: A Concise Guide

85

adaptive pain response. Shrier takes this one step further, by claiming that stretching has an analgesic effect, thus, diminishing the already-delayed pain response, compromising an individual's ability to gauge tissue stress and damage, in effect, disrupting the pain mechanism. 2) Acute stretching has the short-term effect (45 minutes) of decreasing tissue stiffness and increasing tissue compliance, which results in decreased energy absorption by the tissue, a critical risk factor in tissue injury. 3) Acute stretching also has the short-term effect of increasing the vulnerability of the sarcomere (a type of muscle fiber) to injury, which is more pronounced during eccentric activity, and can result in injury even within the tissue's normal range of motion. 4) Even gentle stretching causes damage to the cytoskeleton (cell wall structure). We will respond to Shrier point by point. 1) The stretch tolerance hypothesis does not, by itself, show that stretching is maladaptive. The best explanation of delayed pain response through stretching is not that the neural network has been "artificially" adjusted, but that the tissues' capacity to withstand injury has been commensurately enhanced. It is no wonder, and even a good thing, that the pain response should be delayed in step with the onset of injury. Regarding Shrier's claim that stretching also has an analgesic effect, no human pain management studies involving biochemical or neural mechanisms could be found to support the claim. 2) Because stretching increases flexibility, there is a trivial sense in which stretching reduces stiffness, that is, where stiffness is understood as the "reciprocal counterpart" (i.e., the opposite) of flexibility. However, this kind of stiffness does not necessarily imply either increased tissue compliance or decreased energy absorption. Several studies found that slow/static stretching has no short-term effect on the passive viscoelastic properties of muscle or the active stiffness of the muscle-tendon unit. s There are several hypotheses afoot to explain changes in range of motion brought about by stretching that do not involve positing decreased stiffness of the tissue (e.g., sensory adaptation, muscle spindle desensitization).6 Indeed, as we noted in Chapter 7, there is evidence to suggest that the inability to absorb applied forces involves a deficit not in stiffness but elasticity.? The most we can say for Shrier on this point is that the evidence is inconclusive. 3) Although eccentric activity has been associated with increased injuries, there is no evidence that typical stretching programs negatively influence the sarcomere, or that they are in any other way to blame for these injuries. 4) Supportive data showing damage at the cellular level in normal human tissue that was stretched by gentle stretching programs coull! not bc found in the literature. Although certain types of dynamic stretching (specifically the more vigorous, fast, ballistic forms) can cause or predispose tissues to injury if inappropriately performed, there is no good evidence that stretching, even dynamic stretching (appropriately administered) generally makes tissues

86

8. Myths About Stretching

more susceptible to injury. To state or imply, without sufficient evidence, that stretching is harmful generally is strange indeed.

Myth 2: Stretching Leads to Damage and Dysfunction Similar to Shrier, S.A. Sahrmann has also claimed that stretching reduces musculoskeletal stiffness and predisposes tissues to injury. In fact, the centerpiece of her Diagnosis and Treatment of Movement Impairment Syndromes is the hypothesis that stretching reduces stiffness by damaging the muscle cells directly, and this reduction in stiffness (as well as strength) leads to tissues being weak and dysfunctiona1. 8 As we saw in the last section, the evidence that stretching reduces stiffness is at best inconclusive, and Shrier himself provides no real justification for the claim that stretching damages muscle cells. In this section, we address Sahrmann's specific justification for the view that stretching affects both the muscle cells directly and, via a reduction in strength, dysfunction. Sahrmann reasons that "because muscle cells are the most elastic components of muscle, they are the component most easily affected by stretching."9 In many activities, she argues, whether sports, fitness, or occupational (including sitting for long periods of time at a desk), one muscle group is predominantly inactive, becoming long and weak, whereas its active antagonists become short and strong, shifting the length-tension curve. Movement patterns of the joint become dysfunctional, resulting in microtrauma and macrotrauma to the joint and supportive tissue. 1O In Sahrmann's recent text, she states that the problem is elongation of tissues, and because stretching does just that, one of the implications of her view is that stretching may lead to dysfunction. Her recommended treatment, note, is not stretching the shortened tissues, but strengthening those that have been elongated and weakened. I I The rationale is that strength training will increase the muscle's stiffness by increasing the number of sarcomeres per unit area, thus, reestablishing the appropriate length-tension curve and stiffness/flexibility balance between agonists and antagonists. The alleged net result will be correct movement patterns, whereas stretching short, strong muscles will only aggravate the condition. The basis of Sahrmann's recommendation here, at least in part, is an analogy between repetitive activities/prolonged sedentary periods and what happens to tissues when joints are immobilized in casts (increase in connective tissue and decrease in sarcomeres per unit area).12 Sahrmann's inference from muscle cells being the most elastic components of muscle to the conclusion that they are, therefore, the component most easily affected by stretching does not follow. This is because there are many other types of tissue involved, including fascia, particularly the enveloping fascia, which, in our view, is the tissue most affected by stretching.

Flexibility: A Concise Guide

87

In fact, it is this stiffer component of the soft tissues that would have to be so affected. If the muscle cells were, as Sahrmann claims, most easily affected by stretching, then we would expect soft tissue damage to occur in the muscles themselves far more often than, say, in tendons, or in the connection between tendons and muscle. Sahrmann's conclusion seems to be based on laboratory research in which isolated tissue testing was performed. There simply is no in vivo evidence that stretching affects the muscle cells as much as its surrounding tissues, or that the muscle fibers are damaged during stretching. Our research indicates that 3S does bring about viscoelastic changes, but that the increased range of motion does not result in damage, nor does it weaken the muscle at its new end-range position. Furthermore, not only is isometric strength maintained, it may also be enhanced. 13 Most sports and well-designed fitness programs do not render one muscle group long and weak and its active antagonists short and strong. Sahrmann, we think, overstates both the frequency and the severity of stiffness/ flexibility imbalances. Some activities, such as jogging, cycling, and sports such as soccer can lead to imbalances, but these are corrigible by stretching as much as, if not more than, by strengthening the lengthened muscle groups. In sedentary occupations in which one must sit at a desk, most of the musculature remains in a reasonably fixed position with limited motion at most joints. Accuracy of finger movements (e.g., in typing) usually require fixed trunk and leg postures, which may lead to imbalances of the sort that Sahrmann alludes to. However, even the latter occupations allow some extraneous movements, and the worker can choose to deviate from the primary work position, and shift between deviations. This is not sufficiently analogous to what happens to tissues when joints have been immobilized in a cast. The increase in connective tissue and decrease in number of sarcomeres per unit area in the restricted tissue after casting should occur to a comparatively small extent during the course of sedate occupational work, and, in our view, has no application to most sporting and fitness pursuits. The position that lengthened tissues are weak and dysfunctional, and that shortened tissues are strong and functional, or perhaps hyperfunctional, just cannot be maintained. Although we have suggested this already, we should also mention certain research that runs contrary to Sahrmann's own, independent of our critique above. One study found that individuals classified with stiff hamstrings had significantly more creatine kinase, muscle tenderness, strength loss, and subjective scores of pain (symptomatic of muscle damage) after eccentric exercise than subjects classified as more compliant. 14 Another study found that prolonged continuous passive stretching decreased stiffness-induced dysfunction. L' The way we see it, when it comes to dysfunction, flexibility is not the culprit, but stiffness often is.

88

8. Myths About Stretching

Myth 3: Stretching Does Not Prevent Injuries We have already examined Shrier's contention that stretching causes injury, specifically that pre-activity stretching predisposes tissues to activityinduced injury. Shrier has also written in support of the weaker hypothesis that pre-activity stretching does not prevent injury.16 In one rather selective literature review, he referred to three studies that found stretching to be detrimental, four that found it to be beneficial, and five that found it to have no appreciable effect on injury rates. l ? Going by the numbers, it would seem that stretching does not prevent injuries, or, more carefully, that the evidence is inconclusive. However, of course, one cannot go simply by the numbers. The quality of the studies involved, in themselves and relative to one another, cannot be ignored. Shrier's review is flawed in precisely this way. He accepts the articles at face value, despite the fact that a number of them are methodologically inadequate. A prime and, for our purposes, illustrative, example is a well-known and often-cited study by a research team led by R.P. Pope. IS In a 12-week basic training program, male army recruits performed a warm-up routine with or without six supervised 20-second static stretches. No significant differences were found on any of the injury risk indices, and the conclusion drawn was naturally, if somewhat surprisingly, that stretching does not prevent injuries. However, there are several important research flaws in this study. 1) There was no control group of subjects who did not perform any warm-up activity whatsoever. The non-stretching part of the warm-up may have enhanced or detracted from flexibility. 2) The training parameters were not controlled. The physical demands of basic training, coupled with ill-fitting boots and the added weight of extra gear, may have negated any possible positive effects of the stretching. Traditionally, those who devise military programs believe that massive energy expenditure from the first day is a necessary component of a successful preparatory program. This assault on the bodies of many less than fit individuals often causes both minor and major injuries. 3) Basic training often leads to a high dropout rate. These dropouts are often caused by the pain and dysfunction of soft tissue failure, which affects tissue flexibility. In this study, there was a large number of dropouts, all in the warm-up only group. The reason for dropping out was the recruits' wish to perform stretching exercises. 4) An injury was defined as a lower limb insult that restricted the subject's duties. This was the major objective outcome measure of the study and was based solely on the clinical judgment of the assigned medical personnel. Because there were no objective measures, this study is impossible to reproduce in an independent follow-up project. 5) An important consideration neglected in this study is the fact that many recruits (as a matter of pride) do not report their injuries, whereas others (as a matter of excessive fatigue or laziness) report injuries they do not really have. 6) Although soft-tissue and bone injury risk were

Flexibility: A Concise Guide

89

reported, no analysis was conducted on the dose-response relationships between the specific six major muscle group stretches and the injury profile, that is, where injuries were related to muscles groups not stretched. 7) No information was gathered regarding medical history. Although age was found to be a risk factor, individuals with previous injuries would have been more likely to re-injure themselves. 8) No mechanism of control was reported regarding such well-documented extrinsic risk factors as footwear. Inadequate footwear has a direct influence on the rate of lower extremity injury in military trainees. 9) Finally, and most importantly, there was no effective stretching program to begin with. A bout of slow/ static stretching lasting less than 30 seconds is inadequate to bring about a significant training effect.l~ Pope's single 20-second bout of slow/static stretching obviously would have a minimal preventive effect on any exercise program that followed, especially so in this case, given the rigors of military training. Since a well-structured slow/static stretching program is far less effective than a 3S program, the latter would have been a better choice for the study. Overall, this was a poorly designed study, and yet many around the world have accepted without question its unwarranted conclusions. In direct contrast to the Pope team's findings are a number of bettercontrolled studies of military trainees. Hartig and Henderson found fewer lower extremity overuse injuries in military trainees who performed regular hamstring stretching exercises during a 13-week infantry basic training course. 20 Another study found that the incidence of musculoskeletal injuries and lower back pain were significantly lower in male military recruits after performing a supervised 20-minute stretching routine both before and after physical training. 21 It is important to note that this program required a total of 40 minutes of stretching, 20 before training and 20 afterward. Spending 40 minutes on aerobic and/or strength exercise is often looked on as a necessary training regimen, but relatively few training programs include a corresponding emphasis on stretching. Leaving aside the military studies, we turn now to sport and dance. As mentioned earlier, injury potential is directly and significantly related to the history of previous injuries. Several studies found that there is a significant relationship between previous lower extremity injuries, ankle, or hip flexibility deficits and increased occurrences of new injuries in dancersY Relatedly, significant flexibility deficits were found in the previously injured hamstrings of sprinters compared with sprinters with healthy hamstrings. 23 It is clear that the success of any approach to injury prevention must take into account subjects' medical history. Individuals, particularly athletes with a history of injury and inadequate flexibility, will benefit from a warmup regimen of flexibility exercises. These individuals cannot be compared straightforwardly with individuals with no previous injury. Yet those who deny the benefits of flexibility and stretching tend to ignore this issue. Indeed, it is common for physical therapists to consider hamstring flexibility

90

8. Myths About Stretching

while developing a prescription of stretching exercises for athletes with lower back pain. 24 Witvrouw's research team found that professional soccer players who had low flexibility of the hamstrings and quadriceps during the pre-season had more injuries to these major muscle groups than more flexible players during the competitive season. 25 Similarly, Cross and Worrell found reduced lower extremity strains in college-level football players after the incorporation of a stretching program. 26 In a study involving 10,393 basketball players, it was found that individuals who did not perform stretching exercises before a game were 2.6 times more likely to have an ankle injury than those who performed a pre-game stretch. 27 Bixler and Jones found players from high school football teams that stretched during halftime had fewer injuries than players from teams that did not stretch during halftime. 28 Krivickas and Feinberg found that male college athletes with inadequate lower extremity flexibility had more injuries over the course of the season. 29 Lack of stretching was also found to be related to higher incidences of hamstring strains in professional soccer players. 3o Deficits were found in the range of inward rotation of the dominant hip and shoulder of professional tennis players. 3' These deficits were associated with shoulder pain, lower back pain, and lumbar extension deficits. Stretching the inward rotators of the hip and shoulder was prescribed both as a treatment and as a preventive measure to counteract any further exacerbation. A research group led by McArdle has suggested that poor flexibility of the lower back and posterior lower extremities may be related to pelvic and lower back pathology.32 In a later text, they recommend several flexibility exercises for the lower back and lower extremities that they suggest may be useful in the prevention of lower back injuries. 33 Finally, the "lack of proof" that Shrier and others claim that stretching during a warm-up does not prevent injury is not supported by the research presented above. Even so, we suggest that more research is required. 34 In future studies, we suggest that the 3S reversal of antagonists technique, which maintains isometric strength at end-range and is three to four times more effective in increasing flexibility than other available stretching methods, should be the protocol of choice. The outcome of such studies would permit reasonable judgments regarding the effect of a quality stretching program on injury prevention.

Myth 4: Stretching Does Not Improve Performance Despite the fact that research supports the view of many experts (both researchers and coaches) who believe flexibility to be a crucial aspect of sport performance, others have claimed that it has no influence on performance.

Flexibility: A Concise Guide

9]

It seems obvious that in sports in which body speed is of paramount importance, flexibility would playa major role. Biomechanists would argue that in running and swimming, where covering distance in the shortest amount of time dictates the results of the contest, greater velocity is achieved by the longer application of force, which, in turn, is achieved by having the joints involved in propulsion exhibit wider excursions (amplitude), and the greater the range of motion, the wider the possible excursions. The greater the flexibility, then, the wider the possible excursions, the longer the application of force, the greater the achievable velocity (all else being equal). Because, as we discussed earlier, stretching need not compromise strength, increased flexibility can, and often does, enhance performance. We turn now to some illustrative examples. One study found that post-stretching increases in hip flexion and extension were associated with improvements in running economy (lower aerobic cost during submaximal exercise) in male college students.') Taking into account both biomechanical and physiological considerations, the study found that dysfunctional and non-productive musculoskeletal movements caused by the lack of flexibility increased metabolic cost and decreased the economy of that activity. In sprint running, an enhanced range of motion of the ankle will increase the distance of the application of force (therefore, greater torque), particularly during plantar flexion and toe-off (propulsion):16 According to Alter, the lack of ankle flexibility can result in reduced stride length, and an increase in vertical displacement (less horizontal displacement) of the runner, resulting in an inefficient running pattern:17 In the elderly, walking speed and the length of stride have been shown to be associated with ankle flexibility.18 Limited ankle range of motion during heel-to-toe movement will increase the magnitude of vertical impact forces transmitted through the body. This, in turn, may increase the risk of urinary problems in specific athletes. 3Y From a physiological viewpoint, a less flexible runner will fatigue more quickly than one with greater horizontal displacement and less vertical displacement per stride. The hip extensors are the primary musculature responsible for propulsion while running. Efficient sprinting requires functionallevels of elasticity of the gluteals and hamstrings. Both the range and strength of these muscles, at touchdown, absorption, and propulsion, are necessary to sprint without injury. A kinesiological analysis of the competitive swimming strokes reveals that a greater than normal range of motion in the shoulder joints, knees. and feet are necessary for high-level performance. Shoulder flexibility is important in butterfly, backstroke, and freestyle swimming.~11 Without good range of motion of the shoulder girdle, effective and efficient propulsion simply cannot be achieved. Similarly, an adequate level of vertebral column flexibility, particularly extension, is required to achieve the correct posture during the arm recovery phase of the breaststroke.~' Velocity is generated

92

8. Myths About Stretching

during the breaststroke with sufficient flexibility of the hips and knees of the swimmer. 42 Good ankle and intertarsal flexibility are critical for force production during propulsion in all four strokes. 43 The same biomechanical principle applies to the golf swing. The greater the range of motion of the joints responsible for acceleration, the greater the application of force, the greater the velocity of the full golf swing. Limited thoracic spine and shoulder girdle mobility will result in diminished clubhead velocity at ball strike, and, consequently, less shot distance. 44 In many aesthetic sports and dance disciplines, there are specific characteristic motor skills, which must be performed correctly to meet minimum requirements. These skills often demand high levels of flexibility. For example, many classic ballet positions and movements require high levels of flexibility to be performed correctIy.45 It is very clear that dancers, divers, figure skaters, gymnasts, and synchronized swimmers need high levels of flexibility to execute various maneuvers, basic and advanced. As a final and, to some, perhaps a counterintuitive example, we take Olympic-style weightIifting. The squat position adopted during both cleanand-jerk and snatch lifting requires excessive angles at the hips (flexion), knees (flexion), and ankles (dorsiflexion). Without adequate flexibility at these joints, weightlifters cannot perform this necessary, skilled movement effectively. The range of examples we have covered here is selective but representative and useful for our purpose. For "experts" to claim that enhanced flexibility is not necessary for improving performance in many activities seems implausible on its face and indefensible in light of the research mentioned above. How this myth persists is a source of genuine puzzlement.

Myth 5: Stretching Has No Therapeutic Value Earlier we addressed Sahrmann's view that inequities in the length-tension curve and imbalances in muscular stiffnesslflexibility are best addressed not by stretching short, tight muscles but by strengthening elongated, weak ones. We wonder why she did not focus on the combined use of stretching the tight muscles and strengthening the weak. Because she did not write about stretching in her book, she leaves the impression that it is not therapeutically useful. She may in fact emphasize stretching in her clinical work, but has marginalized it in the book. Contrary to this position, stretching has been found to be an important component in the rehabilitation of hamstring injuries. 46 Sahrmann is certainly not alone in holding this view. Some believe that stretching does not have a therapeutic effect in coping with, much less resolving, suspected chronic orthopedic pathologies, such as lower back pain. 47 Consistently, however, target subject populations in these studies had pain that was in no way related to deficits in flexibility. The therapeutic

Flexibility: A Concise Guide

93

value of stretching is not undermined simply because there are cases in which compromised flexibility is neither part of nor associated with the condition. There are times when stretching is not an appropriate therapy, just as there are times when open heart surgery is not an appropriate therapy. In cases in which people have functional limitations caused by a lack of flexibility, a therapeutic exercise program of flexibility enhancement would be beneficial. Here are just three examples. For individuals with painful heel syndrome, pain relief is obviously one of the major treatment goals. One non-surgical treatment option is Achilles tendon stretching. One study tested a large group of subjects with painful heel syndrome using either sustained or intermittent stretching of the Achilles tendon and found an increase in flexibility was associated with decreased pain. 48 A similar finding occurred in a group of community-based older adults involved in a regular stretching program for a period of 12-months. Participants reported significant improvements in quality of life and reduced bodily pain.4~ Adherence to the program was an impressive 80%. The issue of when to stretch has been addressed in Chapter 1. Finally, stretching has been shown to be a viable treatment option for patellofemoral pain syndrome'li and plantar fascitis.' 1

Myth 6: All Forms of Stretching Have Similar Effects Many professionals understand and appreciate the differences among various forms of resistance training. They know that a program designed to develop both strength and hypertrophy would result in considerably different outcomes than one designed for local muscular endurance. As well, the differences between various forms of aerobic training, both obvious and subtle, are recognized by many. However, when it comes to flexibility, most people believe that any method of stretching is like any other, even though widely available research tells us that this is not the case. Each method of stretching leaves its own distinctive imprint on the body. When used at the appropriate time, and for the right population, each method can contribute positively to sport, exercise, and rehabilitative programs. However, when the objective is to quickly and efficiently enhance soft tissue elasticity, creating an increased disposition to greater excursions, there is a clear hierarchy of effectiveness. Of the three basic techniques, slow/static, dynamic and PNF, PNF is superior.'2 Of the various PNF derivatives, the 3S method is the most effective and safe.'1 When the objective is meditation, relaxation, and a gentle and effective stretch, yoga would be the method of choice. To quickly prepare for a ballistic sport event, such as golf, low-speed dynamic stretching would be appropriate. For convenience, and simplicity, where such specific needs as mentioned above are not required, the slow/static method is often used. Notwithstanding, we

94

8. Myths About Stretching

stress again that the slow/static method is not representative, as skeptics and opponents of stretching tend to presume, of all stretching methods. Although we are running a bit roughshod over this material here, it should suffice for now to undermine the myth that all stretching is created equal. In Chapter 1, we elaborated on these and related points.

Summary Although some of the research we have discussed here is incomplete, we have exposed a number of myths regarding stretching and flexibility. In general, critics of stretching tend to leave key terms undefined or ill-defined, have incomplete or biased literature reviews, commit hasty generalizations, fail to assess the quality of articles they review, and assume that stretching is homogeneous. The myths we have exposed as false or lacking sufficient justification are: 1) stretching causes injury; 2) stretching leads to damage and dysfunction; 3) stretching does not prevent injuries; 4) stretching does not improve performance; 5) stretching has no therapeutic value; and 6) all forms of stretching have similar effects. To date, there is no reasonable basis to discredit stretching as a beneficial exercise mode in sport, fitness, or rehabilitation.

References 1. Herbert and Gabriel (2002), Shrier (2004), Nelson and Bandy (2005). 2. Holt et al. (1970), Holt (1974), Smith (1982), Holt and Smith (1983), Burke (1995), Holt et al. (1995), Culligan (1996), Holt et al. (1996a), Holt et al. (1996b), Holt et al. (1996c), Holt et al. (1999), Schmitt et al. (1998), Schmitt et al. (1999), Burke et al. (2000a), Burke et al. (2000b), Burke et al. (2000c), Burke et al. (2001), Holt and Pelham (2001), Pelham et al. (2001), Pelham et al. (2002a). 3. Herbert and Gabriel (2002). 4. Shrier (2002). 5. Halbertsma and Goeken (1994), Muir et al. (1999), Magnusson et al. (2000), Hunter et al. (2001). 6. Halbertsma and Goeken (1994), Carter et al. (2000), Shrier (2000), Bjorklund et al. (2001). 7. Wilson et al. (1991a). 8. Sahrmann (1996), Sahrmann (2002). 9. Sahrmann (2002) p 26. 10. Sahrmann (1996), Sahrmann (2002). 11. Sahrmann (1996), Sahrmann (2002). 12. Williams and Goldspink (1978), Williams and Goldspink (1984). 13. Smith (1982), Burke et al. (2000c). 14. McHugh et al. (1999). 15. Selby-Silverstein et al. (1997). 16. Shrier (1999; 2000; 2002; 2005). 17. Shrier (1999).

Flexibility: A Concise Guide 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30. 31. 32. 33. 34. 35. 36. 37. 38. 39. 40. 41. 42. 43. 44. 45. 46. 47. 48. 49. 50. 51. 52.

95

Pope et al. (2000). Bandy and Irion (1994). Hartig and Henderson (1999). Amako et al. (2003). Gans (1985), Reid (1988). Jonhagen et al. (1994). Kolber and Zepeda (2004). Witvrouw et al. (2003). Cross and Worrell (1999), cited by Nelson and Bandy (2005). McKay et al. (2001). Bixler and Jones (1992). Krivickas and Feinberg (1996). Dadebo et al. (2004). Vad et al. (2003). McArdle et al. (2000). McArdle et al. (2001). Herbert and Gabriel (2002). Godges et al. (1989). Alter (1996). Alter (1996). Brach and VanSwearingen (2002). Nygaard et al. (1996). Alter ( 1996). Alter (1996). Alter (1996). Alter ( L996). Holt (2004). Gilbert et al. (1998). Fredericson et al. (2005), Malliaropoulos et al. (2004). Kuukkanen and Malkia (2000). Porter et al. (2002). King et al. (2000). Tyler et al. (2006). Digiovanni et al. (2006). Alter (1996), Cornelius and Hinson (1980), Etnyre and Abraham (1986), Hardy (1985), Holt and Smith (1983), Holt et al. (1970), Pelham et al. (2002a), Smith (1982). 53. Holt et al. (1995).

9 Clinical Concepts and Applications

Flexibility and Range of Motion A major component of physical health and well-being is an individual's ability to successfully perform the activities of daily living. To perform everyday activities, a healthy musculoskeletal system is essential, and this requires adequate levels of muscular strength, endurance, and flexibility. Without a sufficient level of musculoskeletal fitness, the overall quality of life of an individual will suffer and health status will decline. In cases in which physical capacities have been lost because of injury, illness, or disease, rehabilitation can help the individual restore some or all of the physical deficits. An essential component of most physical rehabilitation programs is exercise. Properly prescribed exercise is one of the most effective and efficient therapeutic approaches to restore function. A multitude of exercise protocols have been designed to improve aerobic and anaerobic power, neuromuscular strength and power, endurance, and flexibility. In the clinical setting, each form of exercise is used with specific objectives in mind. Clinicians prescribe flexibility exercises to help patients regain normal range of motion, prevent the recurrence of joint stiffness, and prevent or reverse muscular shortening. The last is a major therapeutic challenge for clinicians, and will be discussed later in this chapter. Each therapeutic program should be individualized, based on the expressed goals of the patient and the requirements recommended by the clinician's expertise. Progress within the program will depend on the changes in the patient's condition in response to therapy, as constrained by the therapeutic objectives and tissue adaptability. This applies not only to flexibility training, but to all exercise prescriptions. There are several factors that limit flexibility and its indicator, range of motion. In the clinical situation, pain, muscle spasm, soft tissue adhesions, From: Musculoskeletal Medicine: Flexibility: A Concise Guide to Conditioning, Performance Enhancement, Injury Prevention, and Rehabilitation By L.E. Holt, T.W. Pelham, and J. Holt © Humana Press Inc., Totowa, NJ 97

98

9. Clinical Concepts and Applications

contractures, and immobilization (inactivity) will greatly influence the range of motion of the movement system. If restricted or excessive range of motion in any movement system is amenable to change through exercise, it is the clinician's responsibility to devise and carry out the appropriate corrective exercises. Should the problem lie beyond the purview of physical therapy, surgery may be needed to correct the abnormality. This is sometimes the case when joint capsules and supporting ligaments are the source of the problem.

Functional Flexibility A key factor in the exercise prescription of the 3S flexibility program is the functional status of the individual, depicted in Graph 9-1. Adequate flexibility is as necessary for effective functioning as adequacy in strength, neuromuscular endurance, and cardiorespiratory capacity. Individuals lack functional flexibility if they demonstrate too little (e.g., frozen shoulder) or excessive (e.g., multidirectional unstable shoulder) range of motion, or pain as they perform the full range of motion. Pain indicates tissue damage, and too little range compromises the ability to accomplish daily tasks. Excessive (joint) range may indicate lack of restorative capacity in the associated tissues once a full excursion is performed. All three involve injured tissue.

State of Functional Flexibility

Perfonnance

Range of motion Hypennobility (dysfunction)

Hypomobility (dysfunction) -------Flexibility-----(State of Functionality)

Graph 9-1. The inverted-U of the flexibility paradigm.

Flexibility: A Concise Guide

99

Unfortunately, therapists, similar to coaches, can and often do devise improper training programs. Errors in the prescription of a stretching program can create or exacerbate an injury. For example, many swim coaches place a great deal of importance on stretching the glenohumeral joints through ranges of motion that are not needed or desired in any of the strokes. They indiscriminately prescribe stretching in areas such as the shoulders (excessive hyperextension), and knees (outward rotation). Both will create undesired laxity in these tissues, and may compromise the functional capacity of the joint and create pain during the required movement patterns. In clinical settings, such improper prescription may be especially detrimental. A second example is evident not only in swimming but in sports such as Olympic flat water canoeing and kayaking, in which coaches will prescribe heavy resistance training over a wide range of glenohumeral movements in an attempt to stretch and strengthen the shoulders. A typical program includes varying forms of "dips," "flies," bench press, and behind-the-head military press. This is done despite the research, which has clearly shown that these exercises combined with the repeated movement patterns inherent in these sports will damage the supportive structures of the shoulder joint.\ Although many athletes have suffered as a result of performing these inappropriate exercises, many coaches continue to prescribe them to unsuspecting athletes. All training exercises must be justified, in the first instance, by doing no harm. Once that is assured, the exercise should have a positive effect and not interfere with effective and efficient functioning of the body's tissues. Training should always remain within the "functional paradigm."

Correcting Muscle Imbalances Williams and Goldspink found that prolonged casting of a joint resulted in an increased amount of connective tissue at the restricted site and a decrease in the number of sarcomeres per unit area in the affected muscles. 2 Sahrmann suggests that the same sequence of events can occur with repetitive movements and habitual positions commonly found in many sports, fitness programs, occupational tasks, and during daily activities (overuse syndromes).' Muscles become shortened and their antagonists lengthened, resulting in a shift in the length-tension curve. She further states that because movement patterns follow a neural program designed to accomplish a goal without pain, compensatory arthrokinematic and osteokinematic movement patterns develop at the joint. The possible result of these compensatory adaptations is macrotrauma and microtrauma. pain, and dysfunction. Her suggested remedy is that the lengthened muscle group should be subjected to hypertrophy-type strengthening exercises. Although she does not specify which type of contractions (concentric or eccentric) are to be used, hypertrophy training is recommended to increase the number of

100

9. Clinical Concepts and Applications

sarcomeres per unit area and to reestablish relative muscle stiffness and flexibility and the balance between agonists and antagonists. She states that this approach, with reinforcement from the therapist, will result in correct movement patterns. However, as mentioned in earlier chapters, although joggers, soccer players, cyclists, and those involved in sedate occupational work do experience decreases in flexibility as a result of repetitive motions involving less than full excursions, this loss of range does not correspond to a true clinical contracture resulting from a cast. Such activities are by no means analogous to prolonged casting of a joint, and this serves to undermine the basis for Sahrmann's hypothesis. Support for our position can be found in work performed by various research groups. Kubo, Kanehisa, and Fukunaga investigated the effects of stretching on strength and the viscoelastic properties of soft tissue. 4 They studied elongation and stiffness of tendon using ultrasonographic imagery and passive torque-angle curve analysis. They were able to determine the relationship between muscle force and tendon stiffness, finding that a 3week stretching program improved flexibility, significantly decreased energy dissipation, but produced no significant change in stiffness. They argued that a stretching program will modify the viscoelastic properties of tendon, and, more specifically, alter the viscosity of tendon, not its elasticity (a more complete discussion of this topic will be presented in Chapter 10). Additional research has shown that a comprehensive stretching program yields increases in flexibility but no diminution in strength. 5 Worrell, Smith, and Winegardner found not only no decrease, but improvements in both isokinetic torque and hamstring flexibility after a stretching program. 6 In addition, flexibility training was found to improve muscular performance during stretch-shortening cycle activities.?

Choosing a Stretching Method In most cases, high momentum dynamic stretching is not recommended for use in the clinical setting. Slow/static stretching may be useful in situations in which the therapeutic goal is to slowly increase planar range of motion. For example, in cases in which a cast has been worn for a period of time and joint movements are reduced, slow/static stretching (in this case of the calf) is recommended. However, in most cases, an active flexibility training regimen is required to quickly and efficiently regain functionality. In these cases, 3S is recommended.

Flexibility and Traditional Chinese Medicine Clinicians use a variety of methods to treat patients with limitations in flexibility. Although the Western scientific medical approach continues to

Flexibility: A Concise Guide

101

dominate the clinical setting, other approaches are gaining in popularity. In traditional Chinese medicine (TCM), one of the popular treatment options available to improve flexibility has been acupuncture. However, little formal research has been conducted on the efficacy of acupuncture as a means of enhancing flexibility in either healthy or clinical populations. To fill this void, we are currently exploring the effects of acupuncture on human performance. After a brief overview of the current state of research on the effects of acupuncture on flexibility, we will present a well-controlled study that our group has conducted.

Flexibility and Acupuncture Acupuncture is a valuable therapeutic modality in the treatment of pain.~ However, the effect of acupuncture on motor performance is still a matter of some controversy.9 The notion that acupuncture has any effect on performance is based on evidence that exercise and acupuncture have several common physiological effects on the body.LO These include the stimulation of production of B-endorphins and adrenocorticotropic hormones, plus activation of neuromuscular spindles, decreased muscle tone, and several cardiovascular responses. I I Neuromuscular spindles are found in skeletal muscles, and are activated by stretch, or strong muscular contractions. Similarly, these receptors, and their afferent nerve fibers, are activated by the application of acupuncture. 12 According to Pelham, Holt, and Stalker, it is the stimulation of these muscle receptors that reduces muscle tone via activation of neural inhibitory pathways.13 This may explain any subsequent increase in range of motion. Acupuncture is a common therapeutic tool used by Canadian physical therapists. '4 In many cases, the goals of treatment with acupuncture are pain management, improved range of motion, and strength development (release of available strength). Although the benefits of acupuncture are the promotion of health for the patient and the associated treatment success for health professionals, there is little scientific information available to support the notion that acupuncture aids in the achievement of these ends. Indeed, to date, there have been no randomized controlled studies on acupuncture and strength, and very few on acupuncture and active flexibility as indicated by range of motion. Few studies have investigated the possible effects of acupuncture on human performance, most strikingly, with regard to active range of motion and flexibility. 15 Although clinicians have found acupuncture to be a useful therapeutic tool to decrease spasticity, their reports are mostly anecdotal and unquantified by outcome measures. In One research team, led by Irnick, attempted to overcome such methodological shortcomings in a randomized trial of acupuncture versus massage and sham laser acupuncture in the treatment of mobility impairments associated with chronic neck pain. '7 Sophisticated measurements of active range of motion of the cervical spine were used, and the range was found to be significantly greater immediately

102

9. Clinical Concepts and Applications

after needle acupuncture than massage or sham laser acupuncture. The researchers concluded that acupuncture may be beneficial with regard to mobility and pain free motion in patients with chronic neck pain. As well, a series of acupuncture treatments during a 3-week period was found to improve pain free shoulder movements in women after ablation and axillary lymphodenectomy.18 However, acupuncture did not improve active range of motion of elbow flexion after delayed onset of muscle soreness induced by eccentric exercise. 19 To date, no study has been published regarding the effects of acupuncture on active range of motion in a healthy population. This is most disconcerting considering the widespread use of acupuncture as a complementary therapy in many rehabilitation programs aimed at improving active flexibility in athlete-patient populations. However, one study conducted by our research group investigated the effects of acupuncture on range of motion in healthy women. 20 Twelve healthy female students served as subjects in a randomized controlled double-blind study, designed to assess a physiological response (i.e., active range of motion) to acupuncture. We hypothesized that subjects would demonstrate active range-of-motion gains in target tissue after acupuncture. Six subjects were randomly assigned to the acupuncture group, and six were assigned to the sham acupuncture group. The sequence of events of the procedure consisted of three phases: before testing, treatment, and after testing.

Phase I-Before Testing: Active range of motion was measured by goniometry and recorded for right and left lower extremity plantar/dorsiflexion, inversion/eversion, and knee and hip extension/flexion. Phase II- Treatment: The physical therapist randomly assigned each subject to either the control (sham) or experimental (acupuncture) group, and treatments were administered. The six individuals assigned to the experimental group received acupuncture in two predetermined points on the right leg (Stomach 32 and Stomach 36) for 15 minutes before testing (Figure 9-1). The other six subjects were exposed to sham acupuncture

FIGURE

9-1. Application of a sterile

3D-mm acupuncture needle to acupoint

Stomach 32.

Flexibility: A Concise Guide

103

(simulation without actual insertion of the needle) for 15 minutes before testing. Visual determination of the sites was precluded for all of the subjects during the experiment. This information was not revealed to either the subjects or the measurement taker. The therapist was not involved in measurements for either of the testing protocols. Phase llI-After Testing: Immediately after the completion of treatment, the active range of motion for the above-mentioned movements was measured and recorded by the tester. Results: A significant acupuncture main effect was observed for right dorsiflexion, right eversion, and right inversion. Average increases were dorsiflexion, 6 degrees; eversion, 9 degrees; and inversion. 7.4 degrees. No other significant effects were found. Discussion: The data collected for active range of motion were significant for three of the eight movements. The significant improvements in dorsiflexion, eversion, and inversion suggest that single-bout acupuncture stimulation of acupoints Stomach 32 and Stomach 36 is associated with increased active range of motion for these movements in healthy young women. The controls, both the sham group and the left leg. showed no significant increase in range of motion. Although not statistically significant, increases of 15.9% for plantarflexion, and 9.3% for hip flexion were found. These have functional significance, if not statistical. To our knowledge, this is the first study to examine the effects of acupuncture on active range of motion in subjects free of musculoskeletal impairment. It has shed some light on the possibility of using acupuncture as both a therapeutic modality for pain and an ergogenic aid for improving performance, for athletic performance is often hindered by limited flexibility. With this in mind, acupuncture may be used as an adjunct for rangeof-motion improvements in athletes for the sole purpose of preventing the recurrence of a persistent injury. However, at this particular point in time, we do not recommend use of acupuncture as an ergogenic aid to athletic performance.

Yoga and Tai Chi Many ancient exercise programs incorporate controlled, precise movement patterns that use many of the major muscle groups of the body. Yoga and Tai Chi are prime examples. It has been suggested that these controlled exercise protocols enhance motor control, agility, and flexibility.21 Many health professionals have advocated these activities for a variety of individuals, including older populations, in an attempt to optimize a number of fitness parameters, including musculoskeletal function. We see great value in these programs and concur with the present popular view. particularly in post-rehabilitation settings.

104

9. Clinical Concepts and Applications

In the clinical setting, we have found that a combination of TCM and the 3S method of stretching is usually the most effective treatment option. This TCM-3S combination has been used successfully for a wide variety of orthopedic conditions, with patients ranging from elite athletes to sedentary individuals, young and old alike.

Clinical Techniques and Modalities Although clinicians use many types of treatments in their attempts to improve the flexibility of a patient, there is no consensus regarding which techniques are best. The following is a review of the most popular methods.

Massage Massage is an ancient therapeutic art. In the past, it was the treatment choice for many pathologies. Nowadays it is a very popular treatment option among individuals with chronic pain. Many practitioners think that massage has a number of therapeutic effects, including a decrease in afterexercise soreness/discomfort, and an increase in concentrations of serotonin and dopamine. These biological changes are thought to facilitate tissue repair. Although we recognize the practical value of massage and recommend its clinical use, more scientific research is needed to confirm whether massage has such particular physiological effects as it is alleged to have.

Soft Tissue Manipulation, Mobilization, and Traction A skilled clinician may decide to perform a specific manipulation to stretch targeted soft tissues. The specific technique will depend on the expertise of the clinician, the profile of the patient (with associated contraindications and precautions peculiar to the patient), and the goals of the treatment. A soft tissue manipulation may be performed in cases in which there is a reduction in range caused by pathological soft tissue adhesions, scarring, and contractures. All manipulations should be controlled and precise. Usually in the physical therapy setting, a soft tissue manipulation is of high velocity and low amplitude. As mentioned above, one of the goals of manipulation is to break periarticular tissue adhesions to allow for correct remodeling. A manipulation is not meant to replace stretching, but in some special cases, its inclusion can enhance the likelihood of achieving a successful outcome.

Flexibility: A Concise Guide

105

Joint play is a patient-passive technique involving movement of the joint by the therapist (Figure 9-2). Normally, each joint has a predictable and specific quality and quantity of movement that varies with joint position. Any deviation from the expected motion characteristics will assist in the identification of conditions responsible for dysfunction. "End feel" involves movement through as full a range as possible, with expected specific characteristic sensations at the end of range. Assessing these characteristics can help identify abnormalities, and the derivations form the basis for specific classifications. There are three normal end feels: soft (soft tissue approximation), firm (capsule/ligament stretching), or hard (bone-to-bone stop ).22 There are six abnormal end feels: less elastic (caused by scar tissue or shortened connective tissue), more elastic (caused by increased muscle tonus, shortened muscles), and springly block (possibly caused by internal derangement in which the rebound is seen and felt).21 The other abnormal end feels, which were identified by Evjenth and Hamberg and others, are: empty (movement stopped by patient because of pain), premature (movement stops before expected), and extended (excessive range, possibly caused by an instability or hypermobility).24 If ligaments and/or capsules have been injured or are dysfunctional, flexibility exercises are clearly contraindicated. Extensive surgical intervention may be necessary. Similarly, soft tissue mobilizations may be considered a treatment option in restoring restricted movement. Although a mobilization may be considered a more conservative treatment than a manipulation, in many cases, this treatment option has the same level of effectiveness. Popular soft tissue mobilization techniques range from mild prolonged direct pressure to sustained strong direct pressure on the fascial restriction. Applied force and speed are significantly less for a mobilization than for a manipulation. The choice of intensity of pressure (compression) will depend on the depth of the tissue the therapist wishes to treat (the deeper the tissue, the greater the pressure). An active variation involves the application of pressure of sufficient force along the fascial restriction using a sliding maneuver. To

FIGURE 9-2. Joint play evaluation is an important component of an orthopedic assessment.

106

9. Clinical Concepts and Applications

perform the precise movement required during the active (sliding) maneuver, a clinician must be familiar with the anatomy and function of fascia that has become restricted, whereas, during direct pressure approaches, a clinician must identify the precise location of the restriction. These techniques are commonly used to treat myofascial pain syndromes (to release myofascial trigger points). Although there is widespread anecdotal evidence supporting the use of these methods, there is little scientific data supporting their efficacy. Traction is routinely used to stretch soft tissue for the purpose of pain relief, in cases of impingement syndromes in particular. A variety of techniques and protocols is used. The particular parameters of a traction technique will be based on the status of the patient, the diagnosis, and the judgment and skill of the clinician. In many cases, such techniques as we have discussed are used in conjunction with other treatment procedures in restoring and maintaining flexibility. In the vast majority of cases, the addition of an effective stretching program will enhance the prognosis, and we recommend that the 3S method, as the most effective, be used.

Thermal Agents The most commonly used adjunct to therapeutic stretching has been the application of thermal agents. There are a variety of methods and delivery mechanisms for using both heat and cold. Moist heat packs, paraffin baths, Hubbard tanks, warm whirlpools, therapeutic pools, and infrared heat lamps are a few of the agents used to deliver heat to soft tissue. The application of heat has been shown to have both local and systemic effects. Common effects can include an increase in local and general circulation (vasodilation), heart rate, respiration, and metabolism. Neurophysiological changes also occur, and these allow the skeletal muscles to relax. With such effects, there are several important contraindications that should be considered before the application of heat to an area. Avoid areas with: 1) altered sensation, 2) impaired circulation, or 3) infection. This is not a complete list of contraindications. There are other factors the clinician must consider before using heat as a therapeutic agent (Figure 9-3). Two principles of thermotherapy that must be considered by the clinician are the desired depth of penetration of the heat and the surface area to be treated. Each thermal agent has advantages and disadvantages in a given situation. For example, moist heat packs are ideal for most musculoskeletal disorders but must be avoided when patients have dermatological conditions. The optimal therapeutic effects of heat occur between 40°C and 45°C. In the clinical setting, for example, there will be less spasm in the cervical muscular tissue with the application of a moist heat pack at 40°C. The soft

Flexibility: A Concise Guide

107

FIGURE 9-3. Example of a thermal agent.

tissue of the hand responds best to 45°C through the application of paraffin baths. The optimal range of application of moist heat pack is from 10 to 20 minutes, depending on the surface and desired depth of heating. It is widely thought that an increase in temperature of tissue through the external application of heat will assist active stretching in the elongation of connective tissue. In neuromuscular terms, elevated temperature decreases neuromuscular spindle activity and increases the activity of the Golgi tendon organ, resulting in soft tissue relaxation. 25 Cryotherapy is the therapeutic use of cold (Figure 9-4). Common agents include ice packs, towels soaked in ice water, ice/cold water baths, ice massage, and cold-compression apparatus. Cryotherapy is used to create an analgesic effect, control inflammation, enhance neuromuscular control (spasticity control and motor response facilitation), and promote muscle relaxation. Contraindications are similar to those for thermotherapy. Cold must not be applied where there is altered sensation or peripheral vascular dysfunction. The clinician must also consider any compromised cardiac function of the patient. Other contraindications may also apply. Cold application by ice pack is usually for 5 to 15 minutes, ice massage is for 7 to 9 minutes. In all cases, duration of application must be carefully monitored. Clinicians should be familiar with the neural effects of ice, because this will interact with any stretching program. The application of cold has been

FIGURE 9-4. Application of cryotherapy.

108

9. Clinical Concepts and Applications

suggested to decrease nerve conduction velocity of small diameter myelinated fibers. In addition, it has been hypothesized that the cooling of lowand high-threshold mechanoreceptors readjusts muscle spindle activity, producing relaxed neuromuscular tissue. Because of the strong influence of cold on neural and neuromuscular tissue, as well as the fact that the 3S method also affects these tissues, we have found that the 3S technique of stretching is effective when used in conjunction with cold application. 26

Electrotherapy Like acupuncture, electrotherapy (Figure 9-5) has been used for pain management. Neuromuscular electrical stimulation (NMES) is a common adjunct therapy to maintain and promote active range of motion in some orthopedic and neurological conditions. In the clinical setting, a therapist may decide to treat a patient who has reduced active extension and flexion of the wrist associated with a Colles fracture with NMES. If there are no complications after several treatment sessions, the patient usually demonstrates a marked improvement in active range of motion, mobility, and function. Limits in active range of motion associated with soft tissue contractures and swelling have been treated successfully by NMES. For neurological conditions such as occur with cerebrovascular accident, in which flexor spasticity is an issue, NMES, in conjunction with passive range-of-motion exercises, has been used successfully.

Ultrasound Ultrasound (Figure 9-6) is a modality commonly used by clinicians for a variety of conditions. Along with anti-inflammatory properties, ultrasound has a number of possible mechanical and thermal effects, including vasodilation, increased metabolism, and muscle relaxation. Ultrasound is also used to enhance active range of motion. A comparative study found that an active warm-up plus ultrasound improved ankle dorsiflexion?? In another

9-5. Application of NMES to the quadriceps.

FiGURE

Flexibility: A Concise Guide

109

FIGURE 9-6. Application of ultrasound to the hamstrings.

study, hamstring flexibility was found to be greater after slow/static stretching combined with ultrasound (at 3MHz at 2.0W/cm2) versus slow/static stretching alone. This study may have implications regarding injury prevention. 28 Various treatment options are available to the clinician attempting to restore a functional level of patient flexibility. In most cases, an appropriate adjunct therapy, in combination with the 3S method, will yield the best results. Even so, specific protocols (selection and sequencing) of adjunct therapies in combination with 3S, or other methods, as appropriate, are clinical judgments based on a number of factors specifically related to each case.

Diabetes Mellitus Diabetes mellitus is a metabolic disease on the rise in the industrialized world. The healthcare and indirect costs associated with this disorder are enormous. A less recognized clinical feature of this disease is its effects on mobility. Multijoint hypomobility (reduced range of motion) is a common complaint of people with diabetes mellitus. 29 Connective tissue alterations, such as an increase in the number of cross-bridges and advanced glycosylation, have been suggested to contribute to the development of hypomobility.30 This musculoskeletal complication is most prevalent in the upper extremities, including the shoulder and hand joints.31 Hypomobility can pose major challenges for the individual with diabetes in vocational, recreational, and daily living activities. A plausible therapy for these individuals might well include a well-designed exercise prescription of flexibility training.

110 TABLE

9. Clinical Concepts and Applications 9-1. Contraindications and precautions for therapeutic stretching

Contraindications Reduced/impaired thermal, joint receptor, and pain sensations (analgesic medication) Joint instability (hypermobility) Conditions, as indicated by a health professional, in which mobilization of tissue is contraindicated (e.g., severe cardiovascular/cerebrovascular condition such as a thrombus) Significant soft tissue tears (as indicated by a health professional) High risk osteochondritis dissecans conditions (as indicated by a health professional) Significant orthopedic conditions (e.g., some fractures) Recommendation from health professional to avoid or terminate exercise Precautions Terminate exercise if experiencing pain, muscle spasm, dizziness, etc. Do not exercise in extreme range of motions (i.e., overstretching) Surgical support devices in area to be stretched Limit activity in extreme environmental conditions (excessive heat, etc.) Use caution with certain orthopedic conditions (e.g., osteoporosis)" Use caution with cardiovascular conditions (e.g., orthostatic blood pressure)" aA

supervised program is recommended.

Contraindications and Precautions As mentioned in Chapter 7, there are a number of contraindications and precautions for any stretching protocol, the more important of which are listed in Table 9-1. The list is not all-inclusive, and individuals with a medical condition are advised to consult a physician before beginning any stretching program. To minimize the risk of injury during rehabilitation, a progressive approach is best. In other words, when the exercise sessions begin, intensity should be low at first, followed by gradual increases to higher intensity. Pace of movement should be moderate, not fast, particularly with those tissues under stretch. It is important that the individual avoid the overstretching that can result from working in the range of motion (usually toward the end range) producing pain. 3S is effective, gentle, and safe in clinical settings, provided that the clinician adheres to a slow, progressive 3S protocol.

Final Remarks Before designing and implementing any therapeutic stretching program, a clinician must conduct a comprehensive biomechanicallkinesiological exam. 32 Objective findings from the assessment will reveal the degree of active and passive range of motion, joint play, the quality of "end feel" and

Flexibility: A Concise Guide

III

the elasticity of the soft tissue. 33 As well, through observation, a well-trained clinician will identify the movement pattern dysfunction and devise the appropriate approach to optimize function. If soft tissue restriction is the primary culprit, stretching is prescribed first.'4 The 3S method, in combination with appropriate adjunct therapy, is often the most effective approach.

References 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30. 31. 32. 33. 34.

Pelham et al. (1995). Williams and Goldspink (1978; 1984). Sahrmann (1996; 2002). Kubo et al. (2002). Smith (1982), Schmitt et al. (1998), Burke (2000). Worrell et al. (1994). Wilson et al. (1992). Batra (1987), Reaves (1988), Sternfeld et al. (1992), Stux and Pomeranz (1995), Lorenz (1997), Solinas et al. (1998). Pelham et al. (2000), Pelham et al. (2001). Jaung-Geng et al. (1995), Andersson (1997), Pelham et al. (2000), Pelham et al. (2001), Pelham and Rowe (2002). Baldry (1989), Karvelas et al. (1996), Andersson (1997), Pelham et al. (2000), Pelham et al. (2001). Gunn (1978), Andersson (1997). Pelham et al. (2000). Pelham and Rowe (2002), Pelham et al. (2000), Pelham et al. (2001). Pelham et al. (2000), Pelham et al. (2001). Batra (1987), Milanov (1991). Irnick et al. (2001). He et al. (1999). Barlas et al. (2000). Best et al. (unpublished manuscript). Boyle et al. (2004), Ray et al. (2001), Tran et al. (2001). Evjenth and Hamberg (1988). Evjenth and Hamberg (1988). Cyriax (1969), Evjenth and Hamberg (1988). Cameron (1999). Burke et al. (2001). Crumley et al. (2001). Greenwell et al. (1999). Tinley and Taranto (2002). Campbell et al. (1985), cited by Soures de Araujo (200U). Schulte et al. (1993). Eujenth and Hamberg (1988). Eujenth and Hamberg (1988). Eujenth and Hamberg (1988).

10 The Mechanisms of Flexibility Enhancement

Each stretching program that achieves an increase in flexibility causes some tissue adaptation. Because the 3S protocol elicits significantly greater alterations in the capacity of the targeted tissue to increase range of motion, we will focus our initial analysis on that method (the effect of slow/static and dynamic stretching will be addressed later in the chapter, when comparisons with 3S are discussed and illustrated). As an active, full reversal of antagonists procedure, 3S is one of many techniques based on the theoretical foundations of proprioceptive neuromuscular facilitation (PNF). The effects of PNF were originally thought to be brought about by and occur within structures of the nervous system. Early theorists and practitioners believed that the mechanism responsible for these effects is to be found in the neuromuscular spindles, Golgi tendon organs (GTOs), and their associated structures in the spinal cord. 1 More recent research has suggested that the mechanical properties of the active tissues are altered when the 3S protocol is used; specifically, that viscoelastic changes occur within the soft tissues that permit greater excursions. 2 The structure and interaction between fascia, tendons, and other soft tissues seem to allow for deformation and realignment through stretching.' Proponents of both views are to be found in the literature. 4 What follows is our account of this phenomenon, in which we propose a more comprehensive, unified theory. As we see it, although the stretching procedure itself is controlled by the immediately adaptive neural mechanisms, prolonged adaptation to the protocol involves the restructuring of the targeted soft tissues through the much-discussed viscoelastic response.

From: Musculoskeletal Medicine: Flexibility: A Concise Guide to Conditioning, Performance Enhancement, Injury Prevention, and Rehabilitation By L.E. Holt, T.W. Pelham, and J. Holt © Humana Press Inc., Totowa, NJ 113

114

10. The Mechanisms of Flexibility Enhancement

The Muscle/Fascia/Tendon Complex Through the years, many models have been proposed attempting to explain the various architectural, mechanical, and force-producing properties of skeletal muscle. Most of these models consist of at least two elements: a contractile component, and an elastic component. 5 Perhaps the most popular model currently includes a contractile and two elastic (series and parallel) components (Figure 10-1). The parallel elastic component is found in the many different levels of fascial organization within the muscle/fascia/tendon complex. The distinctive feature of the parallel elastic component is the high content of elastic fibers, which lie parallel to the contractile component. This includes elastic tissue in the sarcolemma, and elastic tissue surrounding the muscle fibers,

l'--j-

Series elastic

10-1. The three-component model of muscle/fascia/tendon complex. Note the contractile component, series elastic component, and parallel elastic component.

FIGURE

Flexibility: A Concise Guide

115

bundles, and groups (endomysium, perimysium, and epimysium). It is in this component, we think, that most of the elongation in the human muscle/ fascia/tendon complex occurs during 3S stretching.

How 3S Works During a 3S protocol, a 10-second isometric contraction of the stretched agonist causes both activation of the agonist's neuromuscular spindles and a viscoelastic change. Cell bodies of alpha and gamma motoneurons located in the ventral horns of the spinal cord trigger motor responses. Alpha motoneurons activate extrafusal (main contractile) fibers and gamma motoneurons innervate intrafusal fibers within the spindle. The spindles are specialized to detect changes in length, rate of length changes, and tension. Rapid stretching of the spindle results in impulses that facilitate reflex agonist activation (myotatic reflex) while inhibiting the antagonist's motoneurons. This is elicited during a ballistic stretch but not during 3S. A forceful, high-tension stretch will also trigger the GTOs to signal spinal cord interneurons, inhibiting the motor neuron, and relaxing the muscle. Because reflexive shutdown of the agonist does not occur during 3S stretching, we think that this is not responsible for increasing the range of motion when the antagonist contracts. It has been suggested that greater increase in range of motion can be achieved, through the neurological apparatus, by the recruitment of more receptor organs (spatial summation), by the transmission of more impulses per unit of time over the same fibers (temporal summation), and by using higher intensities of the isometric contraction of the agonist. I n other words, the neurophysiological basis of PNF suggests that maximal isometric contraction of the agonist should allow for greater increases in the range of motion of the agonist than contractions of lesser intensity.h However, our research has demonstrated similar range of motion responses at different intensities of isometric contraction under the same time constraints, which indicates that there are other, more subtle variables in the mechanism(s), along with the neurophysiological, that are needed to explain the changes in range of motion resulting from the reversal of antagonists. Our research suggests the hypothesis that a significant level of isometric contraction (i.e., 50% or greater) causes physical disruption of either the gross structures or the intermolecular or intramolecular cross-links between fibers in periarticular connective tissue, and that this results in the viscoelastic effect. However, other researchers have suggested that collagenous fibers allow limited elongation (approximately 10%), until the slack of their wavy

116

10. The Mechanisms of Flexibility Enhancement

bundles is taken up.? The rationale is that deformations of the intramolecular and intermolecular cross-links are unlikely, although morphological changes within the ground substances (concentrations of glycosaminoglycans and water) are more likely. Elastic tissue plays a major role in determining the extensibility of soft tissue. Elastic fibers are composed of coiled chains with weak and widely spaced cross-links. Minimal unidirectional force can elongate these chains. 8 In fact, it has been suggested that elastic fibers can be stretched to 150% of their original length with 20 to 30kg/cm 2 of force. 9 As mentioned earlier, Johns and Wright determined the relative contribution of soft tissues to the total resistance encountered by a joint during movement. 10 The joint capsule, tendons, and ligaments, consisting primarily of collagen, were determined to account for the majority (57%) of resistance to stretch. On the other hand, the fascia account for a significant part (41 %) of the total resistance to movement. In terms of deciding what causes increased flexibility, we consider the connective tissues of the fascia to be the important structures. The sarcomere is incapable of self-induced elongation. However, applied forces have been suggested to increase the contractile component of the sarcomere by as much as 67% of its resting state. 11 After an isometric contraction in the lengthened state, as occurs during the 3S protocol, it is likely that morphological changes occur. Relationships between structures (micro and/or macro) are reinstituted, and a new resting length is established. In response to these new biophysical relationships, neurological responses at all levels are adjusted. Elongation of the soft tissue may be simply one, or a combination, of semipermanent resetting of the coiled chains of the elastic tissue in response to the applied force, semipermanent resetting of the wrapping of the collagen fibers with the breaking of cross-links, or a lengthening of the sarcomere. Of these, the most likely structures to elongate would be the elastic fibers of the fascia. The spindles would adjust to the new length, delaying their message until further into the range of motion, because the tension necessary for firing would come about further in the excursion, i.e., after more range of motion had occurred. We tested this hypothesis by setting up a small experiment on the prediction that the electromyography (EMG) signal from the biceps femoris would be delayed in a sit-and-reach test following a four-rep 3S protocol. 12 Subjects performed 3S stretching on the erector spinae muscles and both sets of hamstrings using the 3S (FlexAbility) machines previously described. Surface EMG was placed on the right biceps femoris before the experiment. Subjects were asked to perform a standard sit-and-reach test before and after each bout of 3S exercise. During each slowly executed sit-and-reach test, the position of the distance indicator on the flexometer was reported by the experimenter to synchronize the distance with the EMG signal on

Flexibility: A Concise Guide

117

I EMG activity (mv)

I Distance (inches) FIGURE 10-2. Schematic representations of electromyograms of right biceps femoris during (A) before stretch sit-and-reach and (B) after stretch sit-and-reach. Note: the initial point of muscle activity (1 mY) was delayed in (B).

the oscilloscope. Both were recorded on videotape. Figure 10-2 shows the typical pattern of EMG activity for both before and after tests. EMG activity consistently occurred later in the after test movement than the before test movement for all subjects. As found in previous investigations, the 3S method was found to be very effective in increasing the sit-and-reach scores (Table 10-1). This new finding indicates that the 3S approach delayed the electrical signal in the targeted muscle to a later point in the range of motion, which suggests that the target muscles were more relaxed at the original end-range point in the sit-and-reach test after this simple method of stretching.

10-1. Initial point of muscle activity (1 mY) in before and after sit-and-reach for subjects

TABLE

After (average score)

Before (average score) Point of EMG activity 16cm

Final score

Point of EMG activity

Final score

28cm

22cm

32cm

118

10. The Mechanisms of Flexibility Enhancement

Although this is a fairly simple demonstration of the neuromuscular effects of 3S, further research should be directed at the relationship between muscle relaxation and the changes in range of motion at selected sites, with different populations. More research is needed with respect to the duration of the changes, and what role intervening activities may play in that process. Studies to examine the relaxation effects in the clinical setting, particularly in combination with other therapies, would not only be interesting, but may prove to be helpful in the management of a number of conditions. It seems that neural mechanisms are an integral part of the adaptation, because they monitor all phases of the procedure, and control muscular response to the repositioning that takes place with each reversal. However, it is clear that much research is needed to determine the exact role that spindles play, and to study the controversial role of GTOs in this process. Thus, the neural apparatus is crucial to performing the exercise, and adapts to the new range of motion by delaying/inhibiting the muscle's response as it passes through the before-test location. Two further questions regarding the delay in EMG response should be addressed. The first is whether the spindle is responsible for the delay or simply reporting the new status of the surrounding muscle/fascia/tendon complex. The second concerns why the effect lasts as long as it does. We think that the answer to both questions lies in the effect of the 3S procedure on the tissues involved in performing the exercise. Because spindles are embedded in the muscle, and the muscle is surrounded at all levels by connective tissue, any demonstrated rearrangement of the apparatus, particularly one that indicates a lengthening, would help us discover the answers. Where within the muscle/fascia/tendon complex could this elongation take place? It would seem that the tissues that allow for an elastic-like process to occur would be the prime sites, and those with less potential for change would contribute proportionally less to the adaptation process. We will consider some possibilities. Muscle tissue is organized in a hierarchical manner. The intact muscle is made up of bundles called fascicles, which contain fibers in parallel or in series. The fibers (cells) are composed of parallel myofibrils, which are made up of sarcomeres connected in series throughout the length of the muscle. These, in turn, are composed of the myofilaments actin and myosin, the contractile elements. When taken from its surrounding fascia, a muscle fiber (sarcomere) can be stretched from a resting length of 1.25 to 3.5 /lm. 13 However, these fibers are never permitted to undergo such a highly elastic effect in vivo, where they are encased within connective tissues designed to transmit their contractile efforts to the bony leverage system to which the muscles are attached. Therefore, it seems logical to assume that the muscle fibers do not create the restricting force when the intact muscle is lengthened, and is not then the site where most of the elongation occurs. Tendon is made up of dense fibrous connective tissue consisting almost entirely of tightly packed collagen fibers. Its organization is similar to

Flexibility: A Concise Guide

119

muscle in that it has fascicles, fibers, and microfibrils. This tissue is designed to withstand great tension to transmit muscle forces onto its bony connections. As such, it is not designed for significant stretching and, therefore, is not the targeted tissue responsible for the elongation effect. Fascia is the intermediary between the contractile elements and the high tensile tendon that attaches to and moves the levers. It is found within and around the muscle tissue, and extends to merge with the tendinous tissues. It also has a hierarchical structure, the muscle being enveloped by the epimysium, the fascicles by the perimysium, and the fibers by the endomysium. The composition of this dense connective tissue is key. Fascia is composed of both collagen and varying amounts of elastin. The latter increases in amount in inverse proportion to the size of the material it envelops. That is, the endomysium has a larger percentage of elastin than the perimysium, which itself has more than the epimysium. In addition, the collagen within the endomysium is arranged in an irregular fashion (reticular fibers), which permits more elongation than regular collagen fibers. This intermediary connecting fascia, we think, is the tissue of adaptation when a stretching program increases the length of the whole muscle/fascia/tendon complex.

A Biomechanical Explanation Biological tissues, such as muscle, fascia, and tendon, exhibit certain characteristics when tested in the laboratory. They are considered to behave elastically when forces/loads are applied to them and the length changes are proportional to those forces. They are thought to behave in a viscous manner when deformation is both time and rate-change dependent. When a viscoelastic material is stretched and then held at the new length, the stress at that length gradually declines. 14 The behavior is viscous in that tension decreases over time, yet elastic in that some degree of tension is maintained. Taylor, Dalton, Seaber, and Garrett simulated PNF stretching in their laboratory using intact muscle/tendon/fascia units of rabbits. I) They concluded that this biological unit responded to stretch via viscoelastic properties only. This was based on the fact that the denervated muscle/fascia/tendon unit responded in exactly the same manner as the intact unit for all factors tested. A research group led by McHugh, using EMG, found that a viscoelastic effect occurred independent of detectable muscle activity.16 Subjects performed a straight leg raise from a supine position to a point 5 degrees less than that point in the range where maximal EMG was previously noted. The stretched position was held for 45 seconds. A significant decrease in force occurred with no observed change in the muscle activity.

120

10. The Mechanisms of Flexibility Enhancement

Surburg has stated that resistance to stretch is provided by the connective tissue framework and sheathing found within and around muscle. 17 However, he emphasized that this was more the responsibility of collagen fibers than of elastin. It seems logical that collagen would provide the greatest resistance to stretch, considering its structure. The actual elongation might then be attributed to the elastin present in the structure. Collagen is tightly cross-linked and resistant to stretch, whereas elastin is less extensively cross-linked and more yielding to any force or load applied to it. When a muscle/fascia/tendon complex is put through a 3S protocol, repeatedly stretched beyond its previous existing range of motion, it could be that the cross-linkages between elastin molecules, and between elastin and collagen molecules, are broken and reformed in an elongated manner, permitting more movement before the unit's resistance once again limits the range of motion. This process produces immediate changes in the exercised tissues, specifically, the agonist muscles that are the focus of each specific exercise. An interesting facet of the 3S method is that the length of time that the effect lasts depends almost entirely on the nature of the activities that the subject performs immediately after the 3S exercise. Culligan demonstrated that a number of exercises thought to be heat producing, and, thus, favorable for maintaining a stretched effect, actually brought about a reduction in range of motion. IS

Theoretical Interpretations of Neural and Tissue Adaptations Similar to the morphological adaptations from chronic resistance training (an increase in the number of sarcomeres), a location-specific increase in the concentration of parallel elastic tissue, or elastin, may occur with a corresponding decrease in dense connective tissue during chronic flexibility training. Acute and chronic stretching may indirectly slow down the activity of fibroblasts involved in the production of inelastic collagen fibers, and retard cross-bridge formation. Stretching may increase the phagocytotic activity of macrophages, thereby decreasing the number of collagen fibers, or alter the amount or concentration of a particular constituent of the ground substance of connective tissue. Changes in the ground substance may take the form of an increased concentration of water within the connective tissue. An increase in the water concentration will increase the distance between the fibers, provide lubrication, and decrease the number of cross-links between fibers. Another change in the ground substance may be a decrease in the concentrations of proteoglycans and glycoproteins. Proteoglycans, sulphate compounds, are involved in cross-bridge formation, and glycoproteins are crucial in the

Flexibility: A Concise Guide

j

Stretching

M,d,"r~,c'~

Comp'","

[

'"""dl

ira"''''

M,'~I, ,ff,"'" [

Pm,lId

"~'"

I

oompo",",

EI~,'"

I

Flexibility

121

Strength training

j Series elastic component

I I

Collagen (cross-bridges)

Stiffness

Graph 10-1. A hypothetical schematic representation of the specificity of exercise at the molecular level of stretching versus strength training. development of adhesion between cells. In essence, acute and chronic flexibility training might aid in the remodeling of the connective tissue. A chronic training adaptation could be an increase in the concentration of elastin, with a corresponding decrease in collagen within the parallel elastic component. Research may find that an increased concentration of elastin may be caused by an increased number of elastin molecules (hyperplasia), or an increase in the size of the elastin molecules (hypertrophy) within the parallel elastic component. There may be a corresponding decrease (atrophy) of dense inelastic tissue within the muscle complex. The response of the elastic components of the muscle/tendon/fascia complex will be training specific (Graph 10-1). This notion is supported by the findings of Smith. 19 In his study, it was clearly demonstrated that significant increases in range of motion could be produced without compromising isometric strength, using a 3S program. 211 A research team led by Burke similarly found that an increase in isometric strength as well as range of motion followed 2 weeks of 3S training. 21

View of Adaptation Mechanisms: The Fascia Hypothesis OUf

In our experiments, flexibility increases achieved through stretching can be lost without subsequent activity, or with activities (as in the case of many sports) that discourage full range of motion, irrespective of the stretching

122

10. The Mechanisms of Flexibility Enhancement

method used to achieve range gains. Often individuals who use slow/static stretching procedures experience small gains in range of motion, and lose those gains in a very short time after the stretch. The typical gains from 3S are not only three to four times greater than other methods, they are also longer lasting, although some range is lost when participants engage in range-restrictive activities. We think that the extensive remodelling of the elastin and elastin-collagen cross-linkages that occurs during 3S accounts for the significant retention of tissue elongation. There is a hierarchy of adaptations that occur as a result of various stretching techniques. Slow/static stretching and yoga primarily affect the

A Figure 10-3A. Schematic drawing of the muscle/tendon/fascia complex during both a slow/static stretch and yoga. We think that these methods primarily affect the tendon and epimysium. 1. Muscle placed in a lengthened position. 2. Greatest tension in tendon and epimysium, some spindle activity. 3. Little effect on endomysium and perimysium during the static hold time. 4. Relatively small increase in viscoelastic effect. 5. Time dependent, the longer the hold, the better the effect.

Flexibility: A Concise Guide

123

tendon and epimysium (Figure lO-3A). Because dynamic stretching is an active technique involving momentum, it affects the tendon, epimysium, and the neuromuscular spindles (Figure lO-3B). By contrast, 3S is both an active and a functional stretching method. Most structures and interactions of the viscoelastic components of fascia (epimysium. perimysium. endomysium). tendon, and other soft tissues, along with neural apparatus

2,3

4

I~I

8'--

.&.....

---1

--1

Figure LO-3B. Schematic drawing of the muscle/tendon/fascia complex during dynamic stretching. In c.ntrast to slow/static and yoga. there is more sarcomere activity during a dynamic stretch. elicited by a myotatic reflex via muscle spindle activity. Thus. neuromuscular spindle activity is affected along with the tendon and epimysium. This phenomenon may be the reason actual increases in flexibility after dynamic stretching are minimal. 1. Concentric contraction of the antagonists creates momentum in the body part that lengthens the agonist. The more rapid the concentric antagonist contraction, the greater the momentum created. 2. As the attachment points move apart, rising tension is created in the muscle/ fascia/tendon unit. At slow speeds (low momentum). few spindles are activated. 3. As stretching becomes ballistic. the entire muscle/fascia/tendon unit undergoes stretch. including the parallel elastic tissues. storing elastic energy. which is released when the stretch reflex is automatically performed. 4. By proper sequencing of skilled movements. the storage and release of elastic energy is added to the eccentric-concentric contraction of the agonists. creating a more explosive movement (stretch-shorten cycle). This is used extensively in sport and dance.

C Figure 1O-3C. Schematic drawing of the muscle/tendon/fascia complex during 3S. The role of the reversal of antagonists procedure is both unique and critical in 3S stretching. Unlike other techniques, the reversal of neural transmissions does not affect overall muscle stiffness. Although mechanical, contractile, and neural properties of the motor unit are involved during 3S stretching, it is apparent that there is no pathological disruption of the muscle/tendon/fascia complex. The isometric contraction while the muscle is lengthened creates tension in the elastic components in the endomysium, perimysium, and epimysium. This is not achieved by the other methods, which is the reason for the superior "lengthening" when the antagonist concentrically contracts and/or light pressure is applied. 1. Muscle placed in a lengthened position, greatest tension on tendon and epimysium, some spindle activation. 2. Isometric contraction creates tension via sliding filaments (4 + 6 = 10 seconds). 3. Tension is transferred to surrounding parallel elastic tissues (perimysium, endomysium) while increasing the tension on the tendon and epimysium. The tension creates a viscoelastic effect, elongating the elastin/elastin-collagen structures within the perimysium and endomysium (2 seconds relaxation). 4. The "release" of this tissue permits greater range of motion when the antagonist contracts concentrically (3 seconds).

Flexibility: A Concise Guide

125

(spindles, GTOs and associated structures in the spinal cord) are affected (Figure lO-3C). The preceeding repesent our models of the neuromuscular activity of the muscle/tendon/fascia complex during various stretching procedures. The operational mechanisms of each stretching technique differ. Therefore, the components of the muscle/tendon/fascia complex are potentially affected by and highly dependent on which stretching technique is used. A 3S training prescription involves specific instructions on intensity, direction, and speed of movement. 3S flexibility training enhances motor control by establishing correct motor unit recruitment and coordination. Thus, 3S maintains force production and neuromuscular efficiency. As such, 3S flexibility training can be used to reestablish muscle balance, postural alignment, and functional retraining. 3S is a comprehensive approach to flexibility training, and is a superior stretching technique.

References 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13.

14. 15. 16. 17. 18. 19. 20. 21.

Kabat (1952), Knott and Voss (1955). Schmitt et al. (1999). Fung (1967). Hellebrandt et al. (1956), Thomson and Chapman (1998), Taylor et al. (1990), Shrier (2004b). Hill (1938). Alter (1988). Sapega et al. (1981). Alter (1988). Fawett (1986). Johns and Wright (1962). Alter (1988). Pelham et al. (2002c). Fox et al. (1993). Fung (1967), Janssen et al. (1996). Taylor et al. (1990). McHugh et al. (1992). Surburg (1986). Culligan (1996). Smith (1982). Smith (1982). Burke et al. (2000c).

Conclusion

Many questions remain regarding the theoretical, experimental, and practical aspects of flexibility. First, there is a need to increase the number of researchers concerned with flexibility. This would augment not only the amount but also, in all likelihood, the quality of flexibility-related research. As important as flexibility is, its significance has been and continues to be woefully underrepresented in the laboratory and literature, not to mention on the playing field. Second, there is a need for significant improvement in both the accuracy and precision of technology used in flexibility research. Three-dimensional analysis, online readouts, field measures, and telemetry are applicable to flexibility research, but have not yet been applied, certainly not in sufficient numbers. The greater the accuracy and precision of measurements obtained in flexibility research, the better the experimental controls and overall research designs, the greater the validity of, and the greater the confidence we can have in, our conclusions. Third, there is a need to improve the equipment designed to augment flexibility. Because slow/static, yoga, and dynamic stretching are performed with minimal equipment, and variations of the "rack" device produce pain and are, thus, not recommended, the only method that lends itself to real technical improvements is 3S. Only one device has been designed to permit the full use of the 3S method. More devices are needed. These new devices should: • • • •

Cover each major muscle group in reproducing the 3S protocol Be safe Be user-friendly, adaptable to all body types and flexibility needs Be progressive, capable of keeping up with and surpassing the improvements it helps to achieve • Provide instantaneous feedback to control all aspects of the exercise

From: Musculoskeletal Medicine: Flexibility: A Concise Guide to Conditioning,

Performance Enhancement, Injury Prevention, and Rehabilitation By L.E. Holt, T.W. Pelham, and J. Holt © Humana Press Inc.. Totowa. NJ

127

128

Conclusion

Further research on stretching should focus on the relationships between: • • • • • • • •

The influence of stretching on strength, muscle power, and endurance The influence of stretching on the force-velocity relationship The relationship between stretching and aerobic power Stretching and the injury prevalence in various sports and activities (including sport- and occupation-specific flexibility training) Stretching and the aging process The influence of muscle fiber type on flexibility training adaptations Sex-specific adaptations and influences (e.g., hormonal influences) The roles of the muscle sense organs, particularly proprioceptors, muscle spindles and GTOs in flexibility and flexibility enhancement

Appendix A: Glossary Incorrect, and, in many cases, contradictory use of terminology related to flexibility has hindered the process of understanding. A major obstacle is that researchers, educators, medical, health, and fitness professionals have defined terms differently. To communicate ideas effectively, terms must be defined in a manner acceptable to those working in the field of human movement (Table A-I). Based on our review of the literature, and our own critical analysis, we present a series of appropriate definitions. TABLE

A-I. Definitions of fundamental terms related to flexibility

Term Active movement Agonist Antagonist Ballistic stretching Collagen Collagen fiber

Concentric contraction Connective tissue Contractile component (element) Contraindication

Definition Any normal excursion produced by muscular forces Muscle(s) responsible for the movement being considered, or primarily responsible for the exercise performed Muscle(s) responsible for the movement in opposition to the agonist Rapid motion, high momentum stretching of the agonist, resulting from a strong and fast concentric contraction of the antagonist "The main supportive protein of skin, tendon, bone, cartilage, and connective tissue'" "Constructed primarily of the fibrous protein collagen. Collagen molecules are secreted into the extracellular spaces, where they assemble spontaneously into cross-linked fibers,,2 "The muscle shortens during contraction"3 (activation) "Tissue that binds together and supports the various structures of the body; made up of fibroblasts, fibroglia, collagen and elastin'" "One of the components in Hill-type models of muscle. It represents that ability of contractile proteins to exert a force"s "Any condition that tenders a particular form of treatment undesirable or improper"6 (Continued)

Flexibility: A Concise Guide TABLE

129

A-I. Continued

Term

Definition

Creep

The characteristic elongation of tissue during the application of a constant force over time 'The therapeutic use of cold'" Involves continuous full range of motion activities that may be performed at speeds ranging from slow (low momentum) and smooth to fast/ballistic (high momentum) "The muscle lengthens during contraction'" (activation) "The elongation produced under loading that reverses after the load is removed"" "Formed largely from another fibrous protein, elastin. Elastin has a randomly coiled structure that allows it to stretch and recoil like a rubber band"]O "The ability of the muscle fiber to resume its resting length after being stretched"" The disposition" of body tissuesh to allow, without injury; excursions d at a joint or set of joints. (a) This disposition is amenable to change. Various factors, including age, sex, and lifestyle can affect it (see Chapter 2). When range restriction is caused by tension in soft tissue, the structures may, by means of intrinsic elasticity, return to a normal resting state even if an increase in range has been achieved through a stretching regimen or by some other means. (b) The tissues include muscle, tendon, fascia (a kind of connective tissue in and around muscles), joint capsules, cartilage, ligament, bone, and various components of the nervous system (including neuromuscular spindles). (c) There is an implied restorative capacity, a preserved functionality. For each motion, an excessive excursion may lead to dysfunction. Thus, flexibility, similar to any other physiological parameter, should be viewed as having limitations. (d) By design, each joint and joint group allows specific movements to occur. Limits to each range of motion may include soft tissue contact, bone-to-bone contact, ligament tension. and soft tissue tension. "The inability to perform the tasks or behaviors recognized as essential components of daily life"" The capacity to withstand tension, compression. shear. and elongation forces without damage"

Cryotherapy Dynamic stretching

Eccentric contraction Elastic deformation Elastic fibers

Elasticity Flexibility

Functional limitation Healthy mechanical properties of connective tissue Hyperplasia Hypertrophy Hysteresis Isometric contraction Joint hypermobility Joint hypomobility Load (stress) relaxation Muscle contraction

"An increase in the number of cells in a tissue or organ"" "An increase in the size of a cell or organ"" The permanent change in length of tissue after a stretch (deformation )/relax sequence Activation of muscle that creates tension but does not result in motion Excessive excursion in a joint or group of joints resulting from capsular and/or ligamentous laxity Less than normal range of movement at a joint or group of joints The maintenance of tissue length with less applied force over time Force production as a result of a complex interaction of contractile and regulatory proteins, sarcoplasmic reticulum, calcium, and energy (Continued)

130 TABLE

Conclusion A-I. Continued

Term Muscle relaxation Muscle tissue structure Muscle tone Movement system balance Parallel elastic component of the connective tissue of muscle Parallel elastic component (element) Passive movement Precaution Plastic deformation Range of motion

Series elastic component of the connective tissue of muscle Series elastic component (element) Soft tissue hypermobility Soft tissue hypomobility Stiffness Stretching-induced pain Thermal agent

Definition Complete inactivity of a muscle, its spindles and associated neural apparatus "Actin and myosin myofilaments form myofibrils which are grouped to form muscle fibers; muscle fibers are grouped to form bundles; bundles are grouped to form a muscle,,16 Firmness (turgor) of a muscle as determined by its resistance to compression through palpation "Optimal function of all contributing elements and components resulting in precise arthrokinematics and osteokinematics"17 "The connective tissue between musculotendinous junctions,,18

"One of the components in Hill-type models of muscle. It accounts for the elasticity in muscle that occurs in parallel with the contractile element,,19 Any normal joint excursion produced by forces other than the specific muscles related to that particular movemeneo "Any condition for which special care should be taken prior to rendering a particular form of treatment"21 "The elongation produced under loading that remains after the load is removed"" "1) the measure between beginning and terminal angles, as well as the total degrees of motion, traversed by a joint moved by active muscle contraction or by passive movement. 2) Joint movement (active, passive, or a combination of both) carried out to assess, preserve, or increase the arc of joint motion"'3 "The connective tissue between and including the musculotendinous junctions and the tendoperiosteal junctions";26 does not include actin-myosin cross-bridges

"One of the components in Hill-type models of muscle. It accounts for the elasticity in muscle that occurs in series with the contractile element,,27 Greater than normal range of movement ordinarily restricted by soft tissue, that is safely restorable through muscular control Restricted range of motion brought about by soft tissue injury, disease, or contracture Passive resistance to an applied force Noticeable discomfort usually experienced near end of range of motion during excessive stretching "A physical agent that can increase or decrease tissue temperature ,,24 "The therapeutic use of heat,,25 Thermotherapy The degree to which tissues yield to a deforming force Tissue compliance "Having both viscous and elastic properties"28 Viscoelastic "The physical property of resisting the force tending to cause a Viscosity substance to flow, caused by friction between the molecules of a substance"'9 Viscoelastic properties "Complex mechanical behavior of a material because the resistance force in the material is depending on elongation (elastic) and the rate (viscous) at which the force is applied"30

Flexibility: A Concise Guide

131

References 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30.

Cameron (1999) p 465. Marieb (1995) p 115. American Academy of Pediatrics (2001) Table 1. Cameron (1999) p 466. Enoka (1994) p 415. Cameron (1999) p 466. Cameron (1999) p 466. American Academy of Pediatrics (2001) Table 1. Cameron (1999) p 466. Marieb (1995) p 115. Marieb (1995) p 249. Cameron (1999) p 468. Adapted from BC section, Orthopaedic Division, CPA [No Date) p 5. Fox et al. (1993) p 683. Fox et al. (1993) p 683. BC section, Orthopaedic Division, CPA [No Date) p 9. Sahrmann (1996) p 3. BC section, Orthopaedic Division, CPA [No Date) p 13. Enoka (1994) p 421. Adapted from Maitland (1988) pix. Cameron (1999) p 467. Cameron (1999) p 467. Dirckx 2001 p 838. Cameron (1999) p 468. Cameron (1999) p 468. BC section, Orthopaedic Division, CPA [no date) p 13. Enoka (1994) p 424. Cameron (1999) p 458. Cameron (1999) p 458. Knudson et al. (2000) Table 1.

Appendix B: Applied Anatomy of 3S Stretches TABLE B-1. Applied anatomy of 3S stretches Exercise Hip extensors

Hip adductors

Hip flexors

Agonist Hip extensors: biceps femoris. semimembranosus, semitendinosus, gluteus maximus. adductor magnus Hip adductors: adductor longus, adductor brevis. adductor magnus. gracilis. pectineus Hip flexors

Antagonist Hip l1exors: iliacus. pectineus. psoas. rectus femoris. sartorius

Hip abductors: tensor fascia lata, gluteus medius. gluteus minimus Hip extensors (Continued)

132 TABLE

Conclusion B-1. Continued

Exercise

Agonist

Antagonist

Hip inward rotators

Hip inward rotators: adductor magnus, gluteus medius, gluteus minim us, tensor fascia lata

Hip outward rotators Plantar flexors

Hip outward rotators

Hip outward rotators: gluteus maximus, obturator extern us, obturator internus, piriformis, quadratus femoris, gemelli superior, gemelli inferior, sartorius Hip inward rotators

Shoulder extensors

Shoulder horizontal adductors Shoulder inward rotators Wrist flexors

Trunk extensors

Trunk lateral flexors

Trunk rotators

Neck quadrant

Plantar flexors: gastrocnemius, soleus, plantaris, flexor digitorum, flexor hallucis longus, tibialis posterior Shoulder extensors: latissimus dorsi, pectoralis teres major (sternocostal head) Shoulder horizontal adductors: pectoralis major, anterior deltoid, coracobrachialis Shoulder inward rotators: pectoralis major, latissimus dorsi, teres major, subscapularis Wrist flexors: flexor carpi radialis, flexor carpi ulnaris, palmaris longus, flexor digitorum superficialis, flexor digitorum profundus Trunk extensors (bilateral action): erector spinae (iliocostalis, longissimus, spinalis), multifidus, semispinalis thoracis Trunk lateral flexors (unilateral action): same side external oblique, internal oblique, quadratus lumborum, iliocostalis lumborum, longissimus thoracis Trunk rotators: iliocostalis lumborum, quadratus lumborum, internal oblique with opposite external oblique, serratus posterior, rotatores Sternocleidomastoid, scalenes, splenius capitus, splenius cervicus, upper trapezius

Dorsiflexors: tibialis anterior, extensor digitorum longus, extensor hallucis longus Shoulder flexors: anterior deltoid, biceps brachialis (long head), pectoralis major (clavicular head) Shoulder horizontal abductors: posterior deltoid, teres minor, infraspinatus Shoulder outward rotators: posterior deltoid, infraspinatus, teres minor Wrist extensors: extensor carpi radialis longus, extensor carpi radialis brevis, extensor carpi ulnaris, extensor indicis, extensor digitorum Trunk flexors (bilateral action): rectus abdominis, psoas major, external oblique, internal oblique Opposing group of trunk lateral flexors

Opposing group of trunk rotators

Flexibility: A Concise Guide

133

Appendix C: Research on the FlexAbility Machines Research from the Sport Science Laboratory at Dalhousie university has compared machine-aided 3S, slow/static, and dynamic stretching. In one study, male university students, ages 22 to 31 years, were instructed to perform a random sequence of testing and stretching techniques (Table C1). Selection of subjects was restricted to individuals who were without muscular and orthopedic impairments of the legs, hip, and trunk and not on cardiovascular medication. 3S stretching was performed using the FlexAbility trunk extensor (erector spinae) and hip extensor (hamstrings) machines (prototypes). All subjects performed all three methods during each day of exercise. All possible combinations were performed and the order was randomized. The machine-aided 3S protocol involved subjects performing a lO-second contraction during the isometric phase (4-second build-up, 6-second hold, 2-second relaxation, 3-second move to reposition) whereas intensity was standardized (50% perceived maximal voluntary isometric contraction [PMVIC] on the back machine, 75% PMVIC on the hamstring machine) and 4 total reps were performed to complete the protocol. Active before and after sit-and-reach scores were collected. The slow/static trials involved subjects performing a series of 4 reps of slow/static stretching for the back and both hamstrings. The stretched position was similar to that found on the FlexAbility trunk extensor machine and the FlexAbility hip extensor. The positions were obtained slowly and then held for 6 seconds, with the actual stretching time for all protocols approximately the same. Active before and after sit-and-reach scores were collected. Regarding the fast/ballistic stretch, subjects performed a series of 4 reps of six bounding stretches (1 per second) for the back and both hamstrings. The same stretched positions used during the slow stretch protocol were performed with the actual stretching time for all protocols approximately the same. Active before and after sit-and-reach scores were collected.

TABLE C-l. Time frame and sequence of testing and stretching Date Days 1 & 2 Days 3 & 4 Days 5 & 6 Days 7 & 10 Days 11 & 12 Days 13 & 14

Sequence of testing and stretching Test, slow/static, test, fast/ballistic, test, 3S, Test, slow/static, test, 3S, test, fast/ballistic, Test, fast/ballistic, test, slow/static, test, 3S, Test, fast/ballistic, test, 3S. test, slow/static, Test, 3S, test, fast/ballistic, test, slow/static, Test, 3S, test, slow/static, test, fast/ballistic,

test test test test test test

134

Conclusion

The flexibility of subjects was measured on the sit-and-reach test apparatus. 1 Before the experiment, all five subjects were initially tested using the standard sit-and-reach active ranges. After each stretching trial, all subjects were retested. For the three stretching techniques, before and after differences were significant (P < 0.05). In addition, paired t test analysis showed significant differences between machine-aided 3S and slow/static (P < 0.03) and fast/ ballistic (P < 0.01) (Table C-2). Research findings regarding machine-aided 3S include: • Significant increases in flexibility whether measured passively, actively, or dynamically • Equal to or better (2 of 10 variables measured) than manual 3S exercises • Safer than manual methods • Works effectively with hot/cold modalities • Promotes muscle relaxation • Cardiovascular changes (heart rate and blood pressure) during 3S machine-aided exercises well within guidelines recommended by the American College of Sports Medicine 2

C-2. Change in sit-and-reach for slow/static, fast/ ballistic, and machine-aided 3S

TABLE

Group

Change (inches)

Slow/static Fast/ballistic Machine-aided 3S

'/2 a 1/

(1

2

llt/,b,c

ap < 0.05 compared with baseline (same group). b p < 0.01 compared with fast/ballistic. 'P < 0.01 compared with slow/static.

The FlexAbility LE 1000 is the only mechanized system based on 3S, and is designed for lower limb and lower back exercises, examples of which can be seen in Appendix D. It is user-friendly, providing constant feedback on all aspects of each exercise, and controlled entirely by the exercising person. Indeed, when an individual performs a 3S maneuver on the flexibility machine, the hand control display unit shows the angular displacements, isometric torques, number of seconds, and number of repetitions. This information is stored on a computer. Warning lights and buzzers are engaged should the individual performing the exercise exert force beyond the preselected level. The FlexAbility LE 1000 is adaptable to a wide range of body sizes, shapes, ages, and levels of physical conditioning. It is suitable for:

Flexibility: A Concise Guide

135

• Rehabilitation settings, i.e., physiotherapy, occupational therapy, athletic therapy, and chiropractic applications • Fitness centers catering to the general population interested in complete exercIse programs • Sport and dance in which an increase in range of motion is important for improving performance • Sport and dance in which minimizing injury is important

References 1. Holt et al. (1999). 2. Holt et al. (1995).

Appendix D: Machine and Solo 3S Exercises Low back

Hip flexors

136

Conclusion

Hamstrings

Calf

Shoulder extensors B

Flexibility: A Concise Guide

137

Shoulder horizontal adductors B

Hip flexor

Iliotibial band

138

Conclusion

Appendix E: Recommended Exercises for Specific Activities This appendix contains a list of various physical activities, each paired with an activity-specific set of basic stretching exercises that can serve as the foundation for a training program (Table £-1). Coaches, athletes, and dancers should be free to augment this set of stretches with additional exercises as appropriate. Stretching exercises should be performed just before practice, competition, or performance, with a second bout of stretching after the activity to restore any elasticity that may have been lost during the activity. TABLE

E-l. Recommended exercises for specific activities

Activity Archery Australian rules football Badminton Baseball/softball (all positions) Basketball Cricket Curling Cycling/spinning Dance Diving Equestrian events Fencing Field hockey Figure skating Fitness (aerobics-land) Fitness (jogging) Fitness (resistance exercise) Fitness (gardening) Fitness (walking) Football (all positions) Football (quarterback) Golf Gymnastics Handball (4 wall) Ice hockey (defense/forward) Ice hockey (goaltenders) Lacrosse Martial arts Paddling (canoe) Paddling (kayak) Rowing Skating (figure) Skating (speed) Skiing (alpine/Nordic) Soccer Squash/racquetball Swimming (breaststroke)

Stretching exercises

7,8, 11, 12, 13 1,2,3,6-14 1,2,3,6,7,8,9, 10, 13 1,2,3,6,7,8,9,10,13 1,2,3,6,7,8,10 1,2,3,6,7,8, 10, 12 1, 2, 3, 6, 11, 13 1,2,3,6,8 1-8,11-14 (15-18 as needed) 1,3,6,7,8,11-14 1,2,3, 11, 14 1, 2, 3, 6, 12, 13 1,2,3,6,10,11,13 1-6, 11-14 (15-18 as needed) 1,2,3,6,8,12,13 1,2,3,6,8,13 1,2,3,6,8,10,11-13 1,2,3,6, 10, 11-13 1,2,3,6,8, 13 1,2,3,6,8,10-14 1,2,3,6,8-14 1,5,6, 10, 13, 14 1,2,3,6-14 (15-18 as needed) 1,2,3,6-10,13,14 1,2,3,6,8,10-14 1-6, 10-14 1,2,3,6,8,9,10,13,14 1,2,3,6-14 (15-18 as needed) 1-8, 10, 11-14 3,6,7-14 1,3,6,8, 10-14 1-6,8, 11-14 1-6, 11-14 1,2,3,6,11-14 1,2,3,6,11-14 1,2,3,6-14 4-10 (Continued)

Flexibility: A Concise Guide TABLE

E-l. Continued

Activity Swimming (other strokes) Table tennis Tennis Track and field (sprinting/hurdling) Track and field (field events) Volleyball Weightlifting (olympic) Weightlifting (power) Wrestling

Stretching exercises

6-10 1,2,3,6-14 1,2,3,6-14 1-6, 11-14 1,2,3,6-14 I, 2, 3, 6-14 1,2,3,6-14 1,2,3.6.7, 11-14 1,2,3,6-14

139

Bibliography

Akeson, W.H., D. Amiel, and S. Woo. 1980. Immobility effects on synovial joints: The pathomechanics of joint contracture. Biorheology 17: 95-110. Alter, M.J. 1988. Science of Stretching. Champaign, IL: Human Kinetics Publishers, Inc. Alter, MJ. 1996. Science of Stretching, 2nd ed. Champaign, IL: Human Kinetics Publishers, Inc. Alter, MJ. 1990. Sport Stretch. Champaign, IL: Leisure Press. Amako, A., O. Takaaki, K. Masuoka, H. Yokoi, and P. Campisi. 2003. Effect of static stretching on prevention of injuries for military recruits. Mil Med 168(6): 442--446. American Academy of Pediatrics. 2001. Strength training by children and adolescents. Pediatrics 107(6): 1470-1472. American College of Sports Medicine. 2000. ACSM's Guidelines for Exercise Testing and Prescription, 6th ed. Philadephia: Lippincott Williams and Wilkins. Anderson, B. 2000. Stretching. Bolinas, CA: Shelter. Anderson B., B. Pearl, and E. Burke. 2002. Getting in Shape, 2nd ed. Bolinas, CA: Shelter Publication, Inc. Anderson, B., and E.R. Burke. 1991. Scientific, medical, and practical aspects of stretching. Clin Sports Med 10(1): 63-86. Andersson, S. 1997. Physiological mechanisms in acupuncture. In: Acupuncture and Related Techniques in Physical Therapy. V. Hopwood, M. Lovesy, S. Mokone, and G. Lewith, eds. New York: Churchill Livingston, pp. 19-39. Asikainen T.M., K. Kukkonen-Harjula, and S. Miilunpalo. 2004. Exercise for health for early postmenopausal women: A systematic review of randomised controlled trials. Sports Med 34(11): 753-778. Bach, D.K., D.S. Green, G.M. Jensen, and E. Savinar. 1985. A comparison of muscular tightness in runners and nonrunners and the relation of muscular tightness to low back pain in runners. J Orthop Sports Phys Ther May-June: 315-323. Baldry, P.E. 1989. Neurophysiological pain suppressing effects of acupuncture. In: Acupuncture, Trigger Points and Musculoskeletal Pain. New York: Churchill Livingston, pp. 74-83. Bandy, W.D., and J.M. Irion. 1994. The effect of time on static stretch on the flexibility of the hamstring muscles. Phys Ther 74(9): 845-850. 141

142

Bibliography

Bandy, W.D., 1.M. Irion, and M. Briggler. 1997. The effect of time and frequency of static stretching on flexibility of the hamstring muscles. Phys Ther 77(10): 1090-1096. Barlas, P., J. Robinson, J. Allen, and G.D. Baxter. 2000. Lack of effect of acupuncture upon signs and symptoms of delayed onset muscle soreness. Clin Physiol 20(6): 449-456. Batra, Y.K. 1987. Electroacupuncture in the treatment of acute painful torticollis. Am] Acupuncture 15(1): 257-259. BC section, Orthopaedic Division, CPA. [No Date]. Extremity/Vertebral 1. BC section, Orthopaedic Division, CPA. Beach, TA., RJ. Parkinson, J.P. Stothart, and J.P. Callaghan. 2005. Effects of prolonged sitting on the passive flexion stiffness of the in vivo lumbar spine. Spine 5(2): 145-154. Bell, RD., and TB. Hoshizaki. 1981. Relationship of age and sex with range of motion of seventeen joint actions in humans. Can ] Appl Sport Sci 6: 202-206. Best, K.L., TW. Pelham, and L.E. Holt. A double blind study on the effects of acupuncture on strength and range of motion in women. Unpublished manuscript. Bixler, B., and RL. Jones. 1992. High school football injuries: Effects of a posthalftime warm-up and stretching routine. Fam Prac Res] 12: 131-139. Bjorklund, M., 1. Hamberg, and A.G. Crenshaw. 2001. Sensory adaptation after a 2-week stretching regimen of the rectus femoris muscle. Arch Phys Med Rehabil 82(9): 1245-1250. Bloomfield, J., P. Fricker, and K.D. Fitch. 1992. Textbook of Science and Medicine in Sport. Champaign, IL: Human Kinetics. Boyle, CA., S.P. Sayers, B.E. Jensen, S.A. Headley, and TM. Manos. 2004. The effects of yoga training and a single bout of yoga on delayed onset muscle soreness in the lower extremity. ] Strength Cond Res 18(4): 723-729. Brach J.S., and J.M. VanSwearingen. 2002. Physical impairment and disability: Relationship of performance of activities of daily living in community-dwelling older men. Phys Ther 82: 752-761. Brodowicz, CR, R Welsh, and J. Wallis. 1996. Comparison of stretching with ice, stretching with heat, or stretching alone on hamstring flexibility. ] Athl Train 31(4): 324-327. Burke, D.G. 1995. A comparison of manual and machine assisted PNF flexibility Techniques. Unpublished master's thesis. Halifax: Dalhousie University. Burke D.G., C.J. Culligan, and L.E. Holt. 2000a. The theoretical basis of proprioceptive neuromuscular facilitation. ] Strength Cond Res 14(4): 496-500. Burke D.G., CJ. Culligan, L.E. Holt, and N.C. MacKinnon. 2000b. Equipment designed to simulate proprioceptive neuromuscular facilitation flexibility training. ] Strength Cond Res 14(2): 135-139. Burke, D.G., L.E. Holt, S.A. MacNeil, and N.C. MacKinnon. 2000c. The effect of hot or cold water immersion on isometric strength training. ] Strength Cond Res 14(1): 21-25. Burke, D.G., L.E. Holt, R Rasmussen, N.C MacKinnon, J.P. Vossen, and TW. Pelham. 2001. Effects of hot or cold water immersion and modified PNF flexibility exercise on hamstring length. ] Athl Train 36(1): 16-19.

Flexibility: A Concise Guide

143

Burke, D.G., TW. Pelham, and L.E. Holt. 1999. The influence of varied intensity and speed of concentric antagonistic contractions on subsequent concentric agnostic efforts. J Strength Cond Res 13(3): 193-197. Calguneri, M., H.A. Bird, and V. Wright. 1982. Changes in joint laxity occurring during pregnancy. Ann Rheum Dis 41: 126-128. Campbell, RR, SJ. Hawkins, P.J. Maddison, and J.P.D. Reckless. 1985. Limited joint mobility in diabetes mellitus. Ann Rheum Dis 44: 93-97. Cameron, M.H. ] 999. Physical Agents in Rehabilitation. Philadelphia: W.B. Saunders. Carter, A.M., SJ. Kinzey, L.P. Chitwood, and J.L. Cole. 2000. Proprioceptive neuromuscular facilitation decreases muscle activity during the stretch reflex in selected posterior thigh muscles. .1 Sport Rehabil 9(4): 269-278. Cavagna, G.A., B. Dusman, and R Margaria. 1968. Positive work done by a previously stretched muscle. J App/ Physiol24: 2]-32. Chapman, E.A., H.A. DeVries, and R Swezey. 1972. Joint stiffness: Effects of exercise on young and old men . .1 Geronto/27: 218-221. Clarke, H.H. 1975. Joint and body range of movement. Phys Fitness Res Dig 5: 1. Cohen, D.B., M.A. Mont, K.R Campbell, B.N. Vogelstein, and J.W. Loewy. 1994. Upper extremity physical factors affecting tennis serve velocity. Am J Sports Med 22(6): 746-750. Corbin, CB., and M.L. Noble. 1980. Flexibility: A major component of physical fitness. J 0 PER 51: 23, 24, 57-60. Corbin, CB. 1984. Flexibility. Clin Sports Med 3(1): 10]-117. Cornelius, W.L, and M.M. Hinson. 1980. The relationship between isometric contractions of hip extensors and subsequent flexibility in males. J Sports Med Phys Fit 20(1): 75-80. Cornelius, W., and A. Jackson. 1984. The effects of cryotherapy and PNF on hip extension flexibility. J Athl Train 19: 183-184, 199. Crosman, L.J., S.R Chateauvert, and J. Weisberg. 1984. The effects of massage to the hamstring muscle group on range of motion. J Orthop Sports Phys Ther NovDec: 168-172. Cross, K.M., and TW. Worrell. 1999. Effects of a static stretching program on the incidence of lower extremity musculotendinous strains. .I Ath/ Train 34(10): 11-14. Crawford H.J., and G.A. Jull. 1993. The influence of thoracic posture and movement on range of arm elevation. Physiotherapy Theory and Practice 9(3): 143-148. Crumley, M.L., P.A. Nowak, M.A. Merrick, CD. Ingersoll, and CL. Stemmans. 2001. Do ultrasound, active warm-up and passive motion differ on their ability to cause temperature and range of motion changes? J Ath/ Train 36(2) (Supplement): S-92. Culligan, C 1996. The effect of varying exercise treatments on the change in range of motion henefits realized through a proprioceptive neuromuscular facilitation training regime. Unpublished master's thesis. Halifax: Dalhousie University. Cureton, TK. 1941. Flexibility as an aspect of fitness. Res Quart 12: 381-391. Cyriax, J. 1969. Textbook of Orthopedic Medicine. London: Hutchinson. Dadebo, B., J. White, and K.P. George. 2004. A survey of flexibility training protocols and hamstring strain in professional football clubs in England. Br J Sports Med 38(4): 388-394.

144

Bibliography

Digiovanni, B.F., Nawoczenski, D.A., Malay, D.P., Graci, P.A., Williams, TT., Wilding, G.E., and J.F. Baumhauer. 2006. Plantar fascia-specific stretching exercise improves outcomes in patients with chronic plantar fasciitis. A prospective clinical trial with two-year follow-up. J Bone Joint Surg Am (Abstract). Dirckx, J.H. 2001. Stedman's Concise Medical Dictionary for Health Professions, 4th ed. Philadelphia: Lippincott Williams & Wilkins. Donatelli, R, and H. Owens-Burkhardt. 1981. Effects of immobilization on the extensibility of periarticular connective tissue. J Orthop Sports Phys Ther 3: 67-72. Draper, D.O., L. Miner, K.L. Knight, and M.D. Ricard. 2002. The carry-over effects of diathermy and stretching in developing hamstring flexibility. J Athl Train 37(1): 37-42. Draper, D.O., and M.D. Ricard. 1995. Rate of temperature decay in human muscle following 3MHz ultrasound: The stretching window revealed. J Athl Train 30(4): 304-307. Dubuc, W.E., and RW. Bohannon. 1985. Device for stretching hamstring muscles: Suggestion from the field. Phys Ther May: 352-353. Dumas, G.A., and Reid, J.G. 1997. Laxity of knee cruciate ligaments during pregnancy. J Orthop Sports Phys Ther 26(1): 2-6. Dummer, G.M., P. Vaccaro, and D.H. Clarke. 1985. Muscular strength and flexibility of two female master swimmers in the eighth decade of life. J Orthop Sports Phys Ther 6: 235-237. Ekstrand, J., M. Wiktorsson, B. Oberg, and J. Gillquist. 1982. Lower extremity goniometric measurements: A study to determine their reliability. Arch Phys Med Rehabil63: 171-175. Enoka, RM. 1988. Neuromechanical Basis of Kinesiology. Champaign, IL: Human Kinetics Publishers, Inc. Enoka, RM. 1994. Neuromechanical Bases of Kinesiology, 2nd ed. Champaign, IL: Human Kinetics. Etnyre, B.R, and L.D. Abraham. 1986. Gains in range of ankle dorsiflexion using three popular stretching techniques. Am J Phy Med 65: 189-196. Evjenth, 0., and J. Hamberg. 1988. Muscle Stretching in Manual, Vol. II. Alfta, Sweden: Alfta Rahab. Fawett, D.W. 1986. A Textbook of Histology, 11th ed. Philadelphia: W.B. Saunders. Feland, J.B., J.W. Myrer, and RM. Merrill. 2001a. Acute changes in hamstring flexibility: PNF versus static stretch in senior athletes. Phys Ther Sport 2(4): 186-193. Feland, J.B., J.W. Myrer, S.S. Schulthies, G.W. Fellingham, and G.W. Measom. 2001b. The effect of duration of stretching of the hamstring muscle group for increasing range of motion in people aged 65 years or older. Phys Ther 85(5): 1110-1117. Flint, M.M. 1964. Relationship of the gravity line tests to posture, trunk strength, and hip-trunk flexibility of elementary school girls. Res Quart 35: 141. Fox, E., R Bowers, and M. Foss. 1993. The Physiological Basis for Exercise and Sport, 5th ed. Madison, WS: Brown and Benchmark. Fredericson, M., W. Moore, M. Guillet, and C. Beaulieu. 2005. High hamstring tendinopathy in runners. Physician Sportmed 33(5): 32-43.

Flexibility: A Concise Guide

145

Fredrick, G.A, and DJ. Szymanske. 2001. Baseball (Partl): Dynamic flexibility. Strength Cond J 23(1): 21-30. Fung, Y.c. 1967. Elasticity of soft tissues in simple elongation. Am J Physiol 213: 1532-1544. Funk, D., AM. Swank, K.J. Adams, and D. Treolo. 2001. Efficacy of moist pack application over static stretching on hamstring flexibility. J Strength Cond Res 15(1): 123-126. Funk, D.C., AM. Swank, B.M. Mikla, T.A Fagan, and B.K. Farr. 2003. Impact of prior exercise on hamstring flexibility: A comparison of proprioceptive neuromuscular facilitation and static stretching. J Strength Cond Res 17(3): 489--492. Gabbe, BJ., Bennell, K.L., and c.F. Finch. 2006. Why are older Australian football players at greater risk of hamstring injury? J Sci Med Sport (Abstract). Gans, A. 1985. The relationship of heel contact in ascent and descent from jumps to the incidence of shin splints in ballet dancers. Phys Ther 65(8): 1192-1196. Germain, N.W., and S.N. Blair. 1983. Variability of shoulder flexion with age, activity and sex. Am Corr Ther J 37: 156-160. Gilbert, C.B., M.T. Gross, and K.B. Klug. 1998. Relationship between hip external rotation and turnout angle for the five classical ballet positions. J Orthop Sports Phys Ther 27(5): 339-347. Girouard, C.K., and B.F. Hurley. 1995. Does strength training inhibit gains in range of motion from flexibility training in older adults? Med Sci Sports Exerc 27(10): 1444--1449. Gleim, G.W., and M.P. McHugh. 1997. Flexibility and its effects on sports injury and performance. Sports Med 24(5): 295-299. Godges, 1.1., H. Macrae, C. Langdon, and C. Tinberg. 1989. The effects of two stretching procedures on hip range of motion and gait economy. J Orthop Sports Phys Ther 7: 350-357. Greenwell, N., J. Harris, K.M. Alexander, J.E. Creelman, K. Bowerman, and J. Hust. 1999. Hamstring extensibility changes using static stretch alone and static stretch combined with ultrasound. J Orthop Sports Phys Ther 29(1): A-7. Greipp, J.F. 1985. Swimmer's shoulder: The influence of flexibility and weight training. Physician Sportmed 13: 92-105. Grgic, A, A.L. Rosenbloon, FT. Weber, B. Giordano, J.1. Malone, J.J. Shuster. 1976. Joint contracture: Common manifestation of childhood diabetes mellitus. J Pediatr 88: 584-588. Gribble, P.A., K.M. Kiewicz, W.E. Prentice, and E.w. Shields. 1999. Effects of static and hold-relax stretching on hamstring range of motion using the FlexAbility LE 1000. J Sport Rehab 8(3): 195-209. Gunn, c.c. 1978. Motor points and motor lines. Am J Acupuncture 6(1): 55-58. Hahn, T., A. Foldspang, E. Vestergaard, and T. Ingemann-Hansen. 1999. Active knee joint flexibility and sport activity. Scand J Med Sci Sports 9(2): 74-80. Halbcrtsma, J.P.K., and L.N.H. Goeken. 1994. Stretching exercises: Effect of passive extensibility and stiffness in short hamstrings of healthy subjects. Arch Phys Med Rehabil 75(9): 976-981. Hardy, L. 1985. Improving active range of hip flexion. Res Quart Exerc Sport 56(2): 111-114. Hartig, DE, and J.M. Henderson. 1999. Increasing hamstring flexibility decreases lower extremity overuse injuries in military basic trainees. Am.l Sports Med 27(2): 173-176.

146

Bibliography

He, J.P., M. Friedrick, A.K Ertan, K Mullin, and W. Schmidt. 1999. Pain-relief and movement improvement by acupuncture after ablation and axillary lymphadenectomy in patients with mammary cancer. Clin Exp Obstet Gynecol 26(2): 84-84. Hedman, T.P., and O.R Fernie. 1997. Mechanical response of the lumbar spine to seated postural loads. Spine 22(7): 734-743. Hedrick, A. 2000. Dynamic flexibility training. Strength Cond J 22(5): 33-38. Hellebrandt, F., S. Houtz, M. Partrdge, and e. Walters. 1956. Tonic neck reflexes in normal human subjects. Am J Phys Med 144-156. Herbert, RD., and M. Oabriel. 2002. Effects of stretching before and after exercising on muscle soreness and risk of injury: Systematic review B M J 325-468. Hernandez-Reif, M., T Field, J. Krasnegor, and H. Theakston. 2001. Lower back pain is reduced and range of motion increased after massage therapy. Int J Neurosci 106(3-4): 131-145. Hewett, TE., 0.0. Myer, and KR Ford. 2001. Prevention of anterior cruciate ligament injuries. Curr Womens Health Rep 1(3): 218-224. Hilbert, J.E., and T. Swensen. 2003. The effect of massage on delayed onset muscle soreness. Br J Sports Med 37(1): 72-75. Hill, A.V. 1938. Heat and shortening and the dynamic constraints of muscle. Proc Res Soc Lond [Bioi] 126: 136-195. Holland, 0.1.1968. The physiology of flexibility: A review of the literature. Kinesiology Review 149-62.

Holland, 0.1., K Tanaka, R Shigematsu, and M. Nakagaichi. 2002. Flexibility and physical functions of older adults: A review. J Aging Phy Activ 10(2): 169-206. Holmes, J.e., A.L. Pruitt, and NJ. Whalen. 1993. Iliotibial band syndrome in cyclists. Am J Sports Med 21(3): 419-424. Holt, J., L.E. Holt, and TW. Pelham. 1996a. Flexibility redefined. Biomechanics in Sports XlII 170-174.

Holt, J., L.E. Holt, and TW. Pelham. 1996b. What research tells us about flexibility-I. Biomechanics in Sports XIII 175-179. Holt, J., L.E. Holt, and TW. Pelham. 1996c. What research tells us about flexibility-II. Biomechanics in Sports XIII 180-183. Holt, J., L.E. Holt, and TW. Pelham. 1996d. Flexibility: The future. Biomechanics in Sports XIII 184-188. Holt, L.E. 1974. Scientific Stretching for Sport (3-S). Halifax, Nova Scotia: Sport Research Ltd. Holt, L.E. 2004. An Experimenter's Guide to the Full Golf Swing. Lantz, NS: Aljalar Publishing. Holt, L.E., and TW. Pelham. 2001. Current cross training and testing techniques and injury implications in ice hockey players. Presented at the international hockey conference: Putting it on Ice: Hockey in Historical and Contemporary Perspective, Halifax, N.S. Holt, L.E., TW. Pelham, and D.O. Burke. 1999. Modifications to the standard sitand-reach flexibility protocol. J Athl Train 34(1): 43-47. Holt, L.E., TW. Pelham, and p.o. Campagna. 1995. Hemodynamics during a series of machine-aided and intensity-controlled proprioceptive neuromuscular facilitations. Can J Appl PhysioI20(4): 407-416. Holt, L.E., TM. Travis, and T Okita. 1970. A comparative study of three stretching techniques. Percept Motor Skills 21: 611-616.

Flexibility: A Concise Guide

147

Holt, L.E., and R.K. Smith. 1983. The effect of selected stretching programs on active and passive flexibility. Proceedings of the International Symposium of Biomechanics in Sports. 54-67. Hubley-Kozey, c.L., and W.O. Stanish. 1982. Neurophysiology of stretching. Prevention and Treatment of Running Injuries. Thorofare, NJ: Slack, pp. 135-145. Hume, P.A, W.G. Hopkins, D.M. Robinson, S.M. Robinson, and S.c. Hollings. 1993. Predictors of attainment in rhythmic sportive gymnastics. J SpOrTS Med Phys Fit 33(4): 367-377. Hunter, D., G. Coveney, and 1. Spriggs. 2001. Investigation into the effect of static stretching on the active stiffness and damping characteristics of the ankle joint plantar flexors. Phys Ther Sports J 2(1): 15-22. Hutchins, G.L. 1965. The relationship of selected strength and flexibility variables to antero-posterior posture of college women. Res Quart 36: 253-269. Hutton, RS. 1992. Neuromuscular basis of stretching exercises. Strength and Power in Sport. Oxford: Blackwell Scientific Publishing, pp. 29-38. Irnich, D., N. Behrens, H. Molzen, A. Konig, J. Gleditsch, M. Krauss, M. Natalis, E. Senn, A. Beyer, and P. Schops. 2001. Randomised trial of acupuncture compared with conventional massage and sham laser acupuncture for treatment of chronic neck pain. B M J 322: 1574-1578. Janssen, K., L. Janmey, P. Noegel, M. Schliwa, W. Witke, and M. Schleiher. 1996. Viscoelastic properties of F-actin solutions in the presence of normal and mutated actin-binding proteins. Arch Biochem Biophys 325(2): 183-189. Jaung-Geng, L., H.S. Salahin, and L. Jung-Charng.1995. Investigation on the effects of ear acupressure on exercise-induced lactic acid levels and the implications for athletic training. Am J Acupuncture 23(4): 309-314. Johns, R.J., and V. Wright. 1962. Relative importance of various tissues in joint stiffness. J Appl PhysioI17(5): 824-828. Johnson, RP., and D.P. Babbitt. 1985. Five stages of joint disintegration compared with range of motion in hemophilia. Clin Orthop 201: 36-42. Johnston, C.A, J.E. Taunton, D.R. Lloyd-Smith, and D.C. McKenzie. 2003. Preventing running injuries. Practical approach for family doctors. Can Fam Physician 49: 1101-1109. Jonhagen, S., G. Nemeth, and E. Eriksson. 1994. Hamstring injuries in sprinters: The role of concentric and eccentric hamstring muscle strength and flexibility. Am J Sports Med 22(2): 262-267. Kabat, H. 1952. Studies of neuromuscular dysfunction XV: The role of central facilitation restoration of motor function in paralysis. Arch Phys Med 9: 667-672. Kabat, H. 1958. Proprioceptive facilitation in therapeutic exercise. In: Therapeutic Exercise. New Haven, Connecticut: Elizabeth Licht, Chapter 12. Kaltenhorn, F.M. 1988. Manual Mobilization of the Extremity .Ioints, Vol. II. Oslo: Olaf Norlis Bokhandel. Karvelas, B.R, M.D. Hoffman, and AI. Zeni. 1996. Acute effects of acupuncture on physiological and psychological responses to cycle ergometry. Arch Phys Med Rehab 77: 1256-1259. Kaufman, K.R, S.K. Brodine, RA. Shaffer, C. W. Johnson, and T.R. Cullison. 1999. The effect of foot structure and range of motion on musculoskeletal injuries. Am J Sports Med 27: 585-593.

148

Bibliography

Kibler, W.E., and TJ. Chandler. 2003. Range of motion in junior tennis players participating in an injury risk modification program. J Sci Med Sport 6(1): 51-62. King, AC, L.A Pruitt, W. Phillips, R. Oka, A Rodenburg, and W.L. Haskell. 2000. Comparative effects of two physical activity programs on measured and perceived physical functioning and other health-related quality of life outcomes in older adults. J Gerontol A Biol Med Sci 55(2): M74-83. Kirchner, G., and D. Glines. 1957. Flexibility of children. Res Quart 28: 16-25. Klinge, K., S.P. Magnusson, E.B. Simonsen, P. Aagaard, K. Klausen, and M. Kjaer. 1997. The effect of strength and flexibility training on skeletal muscle electromyographic activity, stiffness, and viscoelastic stress relaxation response. Am J Sports Med 25(5): 710-716. Knight, CA, CR. Rutledge, M.E. Cox, M. Acosta, and SJ. Hall. 2001. Effect of superficial heat, and active exercise warm-up on the extensibility of the plantar flexors. Phys Ther 81(6): 1206-1214. Knott, M., and D. Voss. 1955. Proprioceptive Neuromuscular Facilitation. New York: Hoeber Medical Division, Harper and Row. Knudson, D.Y., P. Magnusson, and M. McHugh. 2000. Current issues in flexibility. President's Council on Physical Fitness and Sports Research Digest (Washington) 3(10): 1-13. Kreighbaum, E., and K.M. Barthels. 1985. Biomechanics, 2nd ed. Minneapolis, MN: Burgress Publishing. Krivickas, L.S., and J.H. Feinberg. 1996. Lower extremity injuries in college athletes: Relation between ligamentous laxity and lower extremity muscle tightness. Arch Phys Med Rehabil77: 1139-1143. Kolber, M.J., and J. Zepeda. 2004. Addressing hamstring flexibility in athletes with lower back pain: A discussion of commonly prescribed stretching exercises. Strength Cond J 26(1): 18-23. Kubo, K., H. Kanehisa, and T. Fukunaga. 2002. Effect of stretching training on the viscoelastic properties of human tendon structures in vivo. J Appl Physiol Feb; 92(2): 595-601. Kuukkanen, T., and E. Malkia. 2000. Effects of a three-month therapeutic exercise programme on flexibility in subjects with low back pain. Physiother Res Inter 5(1): 46-61. Lehmann, J.F., AJ. Masock, CG. Warren, and J.N. Koblanski. 1970. Effect of therapeutic temperatures on tendon extensibility. Arch Phys Med Rehabil August: 481-487. Leighton, J. 1957. Flexibility characteristics of three specialized skill group of champion athletes. Arch Phys Med Rehab 38: 580-583. Lentell, G., T. Hetherington, J. Eagan, and M. Morgan. 1992. The use of thermal agents to influence the effectiveness of a low-load prolonged stretch. J Orthop Sports Phys Ther 19(5): 200-207. Little, T., and AG. Williams. 2006. Effects of differential stretching protocols during warm-ups on high-speed motor capacities in professional soccer players. J Strength Cond Res 20(1): 203-207. Lorenz, K.Y. 1997. What is acupuncture? In: NIH Consensus Development Conference on Acupuncture. Program and Abstracts. National Institutes of Health, pp. 19-23. Low, J.L. 1976. Reliability of joint measurement. Physiother 62: 227-229.

Flexibility: A Concise Guide

149

Magnusson, S.P., P. Aagaard, and J.1. Nielson. 2000. Passive energy return after stretches of the hamstring muscle-tendon unit. Med Sci Sports Exerc 32(6): 1160-1164. Maitland, G.D. 1988. Vertebral Manipulation, 5th ed. London: Butterworth. Marieb, E.N. 1995. Human Anatomy and Physiology, 3rd ed. Redwood City, CA: Benjamin/Cummings Publishing Company, Inc. Market Research Associates Ltd. 1994. Report on a study to determine the market demand for a new type offlexibility exercise equipment. Halifax: Market Research Associates Ltd. Massey, B.A., and N.L. Chaudet. 1956. Effects of systematic, heavy resistance exercise on range of joint movement in young adults. Res Quart 27: 4151. Mathews, D.K., RW. Stacy, and G.N. Hoover. 1964. Physiology of Muscular Activity and Exercise. New Yark: Ronald Press. McArdle, W.D., F.I. Katch, and V.L. Katck. 2000. Essential of Exercise Physiology, 2nd ed. Philadelphia: Lippincott William & Wilkins. McArdle, W.D., F.I. Katch, and V.L. Katck. 2001. Exercise Physiology, 5th ed. Philadelphia: Lippincott William & Wilkins. McAtee, RE. 1993. Facilitated Stretching. Champaign, IL: Human Kinetics Publishers, Inc. McAtee, RE., and 1. Charland. 1999. Facilitated Stretching, 2nd ed. Champaign, IL: Human Kinetics Publishers, Inc. McCafferty W.B., and S.M. Horvath. 1977. Specificity of exercise and specificity of training: A subcellular review. Res Quart 48: 358-371. McCue, B.F. 1963. Flexibility measurements of college women. Res Quart 24: 316-324. McDonough, A.L. 1981. Effects of immobilization and exercise on articular cartilage: A review of the literature. J Orthop Sports Phys Ther 3: 2-5. McHugh, M.P., D.A.1. Connolly, RG. Eston, 1.1. Kremenic, S.1. Nicholas, and G. W. Gleim. 1999. The role of passive muscle stiffness in symptoms of exerciseinduced muscle damage. Am] Sports Med 27(5): 594-599. McHugh, M.P., S.P. Magnusson, G.W. Gleim, and J.A. Nicholas. 1992. Viscoelastic stress relaxation in human skeletal muscle. Med Sci Sports Exerc 24(12): 322-329. McGill, S. 2002. Low Back Disorders. Champaign, IL: Human Kinetics Publishers, Inc. McKay, G.D., P.A. Goldie, W.R. Payne, and B.W. Oakes. 2001. Ankle injuries in basketball: Injury rate and risk factors. Br J Sports Med 35: 103-108. Milanov, I. 1991. Mechanisms of electroacupuncture on spasticity. Am J Acupuncture 19(2): 107-115. Minor, M.A. 2004. Health and physical fitness for the client with multiple joint involvement. In: Physical Rehabilitation in Arthritis. J.M. Walker, and A. Helewa, eds. 2nd ed. St. Louis, MO: Saunders, pp. 265-284. Malliaropoulos N., S. Papalexandris, A. Papalapa, and E. Papacostas. 2004. The role of stretching in rehabilitation of hamstring injuries: 80 athletes follow-up. Med Sci Sports Exerc 36(5): 756-759. Mueck-Weymann, M., G. Janshoff, and H. Mueck. 2004. Stretching increases heart rate variability in healthy athletes complaining about limited muscular flexibility. Clin Auton Res 14(1): 15-18.

150

Bibliography

Muir, I.W., B.M. Chesworth, and A.A. Vandervoort. 1999. Effect of a static calfstretching exercise on the resistance torque during passive ankle dorsiflexion in healthy subject. J Ortho Sports Phys Ther 29(2): 106-115. National Strength and Conditioning Association Certification Commission. 1997. Essentials ofStrength Training and Conditioning Symposium Workbook. Lincoln: National Strength and Conditioning Association Certification Commission. Nelson, R.T., and W.D. Bandy. 2005. An update on flexibility. Strength Cond J 27(1): 10-16. Ninos,1. 2001. A chain reaction: The hip rotators. Strength Cond J 23(2): 26-27. Nygaard, I.E., C. Glowacki, and c.L. Saltzman. 1996. Relationship between foot flexibility and urinary incontinence in nulliparous varsity athletes. Obstet Gynecol 87(6): 1049-1051. O'Driscoll, S.L., and J. Tomenson. 1982. The cervical spine. Clin Rheumatic Dis 8(3): 617-630. Pelham, TW. 1994a. A study of perceived exertion/discomfort while stretching with Flex-SysTM: A pilot study. Technical Report. Halifax, NS: Dalhousie University and PMF Limited (National Research Council of Canada (IRAP #02753E). Pelham, TW. 1994b. Changes in Hip Range of Motion in an Elite Paddler Resulting from a One Week Flex-SysTM Training Program. Technical Report. Halifax, NS: Dalhousie University and PMF Limited (National Research Council of Canada (IRAP #02753E). Pelham, TW. 1994c. Analysis of Muscle Activity while Using Flex-SysTM. Technical Report. Halifax, NS: Dalhousie University and PMF Limited (National Research Council of Canada (IRAP #02753E). Pelham, TW., and H. White. 2003. Preventative aeromedicine for lower back pain in CF helicopter aviators. Presented at the Maritime Helicopter Symposium, Canadian Forces Base-Shearwater in Dartmouth, NS. Pelham, TW., H. White, L.E. Holt, and S.W. Lee. 2005. The etiology of low back pain in military helicopter aviators: Prevention and treatment. Work 24(2): 101-110. Pelham, TW., L.E. Holt, and H. White. 2002a. A comparison of slow, ballistic and machine-aided PNF techniques. Presented at the Annual Scientific Meeting of the Canadian Society for Exercise Physiology, St. John's, Newfoundland. Pelham, TW., L.E. Holt, and H. White. 2002b. Comparison of two durations of isometric contractions in a PNF stretching protocol. Presented at the Annual Scientific Meeting of the Canadian Society for Exercise Physiology, St. John's, Newfoundland. Pelham, TW., L.E. Holt, and H. White. 2002c. The influence of a PNF stretching protocol on resistive muscular activity. Presented at the Annual Scientific Meeting of the Canadian Society for Exercise Physiology, St. John's, Newfoundland. Pelham, TW., L.E. Holt, and M.G. Robinson. 2001. Changes in range of motion resulting from varying intensities of isometric contractions during proprioceptive neuromuscular facilitations. Presented at the Annual Scientific Meeting of the International Symposium on Biomechanics in Sport, San Francisco, CA. Pelham, TW., and P. Rowe. 2002. Effects of a single acupuncture bout on muscular power and work of shoulder rotators in members of the Canadian Navy (Effets d'une seule session d'acupuncture sur la puissance et Ie travail musculaire des muscles rotateurs de I'epaule chez des militaires de la marine canadienne). Physio-Info 3(1): 6-10.

Flexibility: A Concise Guide

151

Pelham, TW., and RJ. Hoyle. 1992. Stretching to maintain ROM in young hockey players. Nat Strength Cond Assoc J 14(5): 58-60. Pelham, TW., L.E. Holt, and R Stalker. 1995. The etiology of paddler's shoulder. Aus J Sci Med Sport 27(2): 43-47. Pelham, TW., L.E. Holt, and RE. Stalker. 1999. The pathologic consequences of strength training: A case series of "paddler's shoulder." Momentum 24(4): 7-12. Pelham, TW., L.E. Holt, and R. Stalker. 2000. Benefits of acupuncture for active patients. Your Patient and Fitness 14(1): 24-26. Pelham, TW., L.E. Holt, and R Stalker. 2001. Acupuncture in human performance. J Strength Cond Res 15(2): 266-271. Phillips, E.A. 1955. Analysis of results from the Kraus-Weber test of minimum muscular fitness in children. Res Quart 3: 316-324. Piscopo, J., and J. Bailey. 1981. Kinesiology the Science of Movement. New York: John Wiley & Sons. Pope, R.P., RD. Herbert, J.D. Kirwan, and BJ. Graham. 2000. A randomized trial of pre-exercise stretching for prevention of lower-limb injury. Med Sci Sports Exerc 32(2): 271-277. Porter, D., E. Barrill, K. Oneacre, and B.D. May. 2002. The effects of duration and frequency of Achilles tendon stretching on dorsiflexion and outcome in painful heel syndrome: A randomized, blinded, control study. Foot Ankle Int 23(7): 619-624. Prentice, W.E. 1983. A comparison of static stretching and PNF stretching for improving hip joint flexibility. J Athl Train Spring: 1-4. Prichard, B. 1987. Stretching for speed. Swimming Technique May-July: 3235. Ray, U.S., R. Mukhopadhyaya, S.S. Purkayastha, V. Asnani, O.S. Tomer. R. Prashad, L. Thakur, and W. Selvamurthy. 2001. Effect of yogic exercises on the physical and mental health of young fellowship course trainees. Indian J Physiol PharmacoI45(1): 37-53. Reaves, W. 1988. Traditional Chinese medicine and the distance runner. Am J AClipunclUre 16(1): 5-10. Reed, J. 2005. Strength and conditioning strategies to reduce the risk of lower back injuries associated with the golf swing. Strength Cond J 27(2): 10- Ll Regan, D.P. 2000. Implications of hip rotators in lumbar spine injuries. Strength Cond J 22(6): 7-13. Reid, D.C. 1988. Prevention of hip and knee injuries in ballet dancers. Sports Med 6(5): 295-307. Roetert, E.P., TS. Ellenbecker, and S.W. Brown. 2000. Shoulder internal and external rotation range of motion in nationally ranked junior tennis players: A longitudinal analysis. J Strength Cond Res 14(2): 140-143. Russell. P.. A. Weld, MJ. Pearcy, R. Hogg, and A. Unsworth. 1992. Variation in lumbar spine mobility measured over a 24-hour period. Br J Rhellmat 31 (5): 329-332. Saal, J .S. 1987. Flexibility training. In: Rehabilitation of Sports Injuries. J .A. SaaL ed. Philadelphia: Hanley and Belfus, Inc., pp. 537-554. Sady, S.P.. M. Wortman, and D. Blanke. 1982. Flexibility training: Ballistic. static or proprioceptive neuromuscular facilitation? Arch Phys Men Rehahil June: 261-263.

152

Bibliography

Sahrmann, S. 1996. Diagnosis and Treatment ofMovement System Imbalances Associated with Musculoskeletal Pain. St. Louis: Washington University. Sahrmann, S.A. 2002. Diagnosis and Treatment of Movement Impairment Syndromes. St. Louis: Mosby, Inc. Salzmann, e.Y. 1982. Sport massage: A means of relieving pain and preventing further injuries. Canadian Runner February: 24-27. Sapega, A.A., Te. Quedenfeld, RA. Moyer, and RA. Butler. 1981. Biophysical factors in range-of-motion exercise. Physician Sportsmed 9(12): 57-65. Sawyer, P.e., TL. Uhl, e.G. Mattacola, D.L. Johnson, and J.W. Yates. 2003. Effects of moist heat on hamstring flexibility and muscle temperature. J Strength Cond Res 17(2): 285-290. Schilling, B.K., and M.H. Stone. 2000. Stretching acuter effects on strength and power performance. Strength Cond J 22(1): 44-47. Schmitt, G.D., TW. Pelham, and L.E. Holt. 1998. Changes in flexibility of elite female soccer players resulting from a flexibility program or combined flexibility and strength program. Clin Kines 52(3): 64-67. Schmitt, G.D., TW. Pelham, and L.E. Holt. 1999. A comparison of selected protocols during proprioceptive neuromuscular facilitation stretching. Clin Kines 53(1): 16-21. Schramm, TM., RW. Latin, K. Berg, and W. Stuberg. 2001. The relationship between physical activity and flexibility. Inter Sports J 5(2): 1-9. Schulte, L., M.S. Roberts, e. Zimmerman, J. Ketler, and L.S. Simon. 1993. A quantitative assessment of limited joint mobility in patients with diabetes. Goniometric analysis of upper extremity passive range of motion. Arthritis Rheum 36(10): 1429-1443. Sechrist, W.e., and G.A. Stull. 1969. Effects of mild activity, heat applications, and cold applications on range of joint movement. Am Corr Ther J July-Aug: 120-123. Selby-Silverstein, L., W.D. Farrett, BT. Maurer, and H.J. Hillstrom. 1997. Gait analysis and bivalved serial casting of an athlete with shortened gastrocnemius muscles: A single case design. J Ortho Sports Phys Ther 25(4): 282-288. Shellock, F.G., and W.E. Prentice. 1985. Warming-up and stretching for improved physical performance and prevention of sports-related injuries. Sports Med 2: 267-278. Shrier, 1. 1999. Stretching before exercise does not reduce the risk of local muscle injury: A critical review of the clinical and basic science literature. Clin J Sport Med 9(4): 221-227. Shrier, 1. 2000. Myths and truths of stretching. Physician Sportsmed 28(8): 5763. Shrier, 1. 2002. Does stretching help prevent injuries. In: Evidence Based Sports Medicine. T Best and D. MacAuley, eds. London, UK: BMJ Publishing Group, pp.97-116. Shrier, 1. 2004a. Does stretching improve performance?: A systematic and critical review of the literature. Clin J Sport Med 14(5): 267-273. Shrier, 1. 2004b. Truths, myths and madness of stretching for performance enhancement. Presented at the annual meetings of the American College of Sports Medicine, Indianapolis. Shrier, 1. 2005. When and whom to stretch? Physician Sportsmed 33(3): 22-26.

Flexibility: A Concise Guide

153

Simoneau, G.G., K.E. Wilk, and W.G. Clancy. 1997. Strengthening and flexibility concepts for running. In: Running Injuries. G. N. Guten, ed. Philadelphia: W. B. Saunders Company, pp. 238-253. Smith, CA. 1994. The warm-up procedure: To stretch or not to stretch. A brief review. ] Ortho Sports Phys Ther 19(1): 12-17. Smith, R.K. 1982. A comparison of selected methods offlexibility training. Unpublished master's thesis. Halifax: Dalhousie University. Soares de Araujo, CG. 2004. Flextest. Champaign, IL: Human Kinetics. Solinas, H., L. Mainville, and B. Auteroche. 1998. Atlas of Chinese Acupuncture: Meridians and Collaterals. Quebec: Publishing Canada Inc. Spernoga, S.G., T.L. Uhl, B.L. Arnold, and B.M. Gansneder. 2001. Duration of maintained hamstring flexibility after a one-time modified hold-relax stretching protocol. ] Athl Train 36(1): 44-48. Sternfeld, M., Y. Finkelstein, A Eliraz, and I. Hod. 1992. Runner's stitch syndrome successfully treated by acupuncture. Am ] Acupuncture 20(3): 213-215. Stux, G., and B. Pomeranz. 1995. Basics of Acupuncture. New York: Springer. Surburg, P. 1986. New perspectives for developing range of motion and flexibility for special populations. Adapt Phys Act Q 3: 227-235. Taylor, D., J. Dalton, A Seaber, and W. Garrett. 1990. Viscoelastic properties of muscle-tendon units: The biomechanical effects of stretching. Am] Sports Med 18: 300-309. Thomson, D.B., and AE. Chapman. 1988. The mechanical response of active human muscle during and after stretch. EurJ Appl Physiol Occup PhysioI57(6): 691-697. Thorstensson, A 1977. Observations on strength training and detraining. Acta Physiol Scand 100: 491-493. Tinley P., and M. Taranto. 2002. Clinical and dynamic range-of-motion techniques in subjects with and without diabetes mellitus. ] Am Podiatr Med Assoc 92(3): 136-142. Toskovic, N.N., D. Blessing, and H.N. Williford. 2004. Physiologic profile of recreational male and female novice and experienced Tae Kwon Do practitioners. ] Sports Med Phys Fitness 44(2): 164-172. Tran, M.D., R.G. Holly, J. Lashbrook, and E.A. Amsterdam. 2001. Effects of Hatha yoga practice on the health-related aspects of fitness. Prev Cardiol 4(4): 165-170. Tseng, CN., Chen, CC, Wu, S.C, and L.C Lin. 2007. Effects of a range-of-motion exercise programme. ] Adv Nurs (Abstract). Tyler, T.F., Nicholas, S.J., Mullaney, MJ., and M.P. McHugh. 2006. The role of hip muscle function in the treatment of patellofemoral pain syndrome. Am ] Sports Med (Abstract). Unick, 1., H.S. Kieffer, W. Cheeseman, and A. Feeney. 2005. The acute effects of static and ballistic stretching on vertical jump performance in trained women . .I Strength Cond Res 19(1): 206-212. Vad V.B., A Gebeh, D. Dines, D. Altchek, and B. Norris. 2003. Hip and shoulder rotation range of motion deficits in professional tennis players. ] Sci Med Sport 6(1): 71-75. Vad, V.B., AL. Bhat, D. Basrai, A Gebeh, D.O. Aspergren, J.R. Andrews. 2004. Low back pain in professional golfers: The role of associated hip and low back range-of-motion deficits. Am] Sports Med 32(2): 494-497.

154

Bibliography

van Gyn, G.H. 1984. Contemporary stretching techniques: Theory and application. In: The Dancer as Athlete. e.G. Shell, ed. Champaign, IL: Human Kinetics Publishers, Inc., pp. 110-116. Wallin, D., B. Ekblom, R Grahn, and T Nordenborg. 1985. Improvement of muscle flexibility: A comparison between two techniques. Am J Sports Med 13: 263-268. Wang, S.S., S.L. Whitney, RG. Burdett, and lE Janosky. 1993. Lower extremity muscular flexibility in long distance runners. J Orthop Sports Phys Ther 17(2): 102-107. Wiksten, D., and e. Peters. 2000. The Athletic Trainer's Guide to Strength and Endurance Training. Thorofare, NJ: Slack Incorporated. Wiktorsson-Moller, M.B. Oberg, l Ekstrand, and J. Gillquist. 1983. Effect of warming up, massage, and stretching on range of motion and muscle strength in the lower extremity. Am J Sports Med 11: 249-252. Williams, P.E., and G. Goldspink. 1978. Changes in sarcomere length and physiological properties in immobilized muscle. J Anatomy London 127: 459-468. Williams, P.E., and G. Goldspink. 1984. Connective tissue changes in immobilized muscle. J Anatomy London 138: 342-350. Williford, H.N., lB. East, FH. Smith, and L.A Burry. 1986. Evaluation of warm-up for improvement in flexibility. Am J Sports Med 14: 316-319. Wilson, GJ., G.A Wood, and B.e. Elliott. 1991a. The relationship between stiffness of the musculature and static flexibility: An alternative explanation for the occurrence of muscular injury. Int J Sports Med 12: 403-407. Wilson, GJ., G.A Wood, and B.e. Elliott. 1991b. Optimal stiffness of the series elastic component in a stretch shorten cycle activity. J Appl Physiol 70: 825-833. Wilson, G.J., B.e. Elliott, and G.A Wood. 1992. Stretch shorten cycle performance enhancement through flexibility training. Med Sci Sports Exerc 24: 116-123. Winton, H.A. 2003. Stretching to prevent injuries. Patient Care 14(6): 23-25. Witvrouw, E, L. Danneels, P. Asselman, D. Have, and D. Cambier. 2003. Muscle flexibility as a risk factor for developing muscle injuries in male professional soccer players. A prospective study. Am J Sports Med 31(1): 41-46. Woolstenhulme, M.T, Griffiths, e.M., Woolstenhulme, EM., and Ae. Parcell. (2006). Ballistic stretching increases flexibility and acute vertical jump height when combined with basketball activity. J Strength Cond Res 20(4): 799-803. Worrell, TW., TL. Smith, and J. Winegardner. 1994. Effect of hamstring stretching on hamstring muscle performance. J Orthop Sports Phys Ther 20(3): 154-159. Wright, Y., and RJ. Johns. 1961. Relative importance of various tissues in joint stiffness. Ann Rheum Dis 20: 36-46. Zernicke, RF, and BJ. Loitz. 1992. Exercise-related adaptations in connective tissue. In: Strength and Power in Sport, Oxford: Blackwell Scientific Publishing, pp.77-95.

Index

A Achilles tendinopathy, 72 Acupuncture, 101-103 clinical studies for, 102-103 inverted-U in, 98 neuromuscular spindles and, 101 range-of-motion and, 101 treatment goals for, 101 Acute stretching, 85, 120-121 Age, 69-70 flexibility and, 69-70 Arthritis, 72 Athletes. See Dancers; Divers; Figure skaters; Gymnasts B Barbells, 14 Breathing, for yoga, 11-12

C Chronic stretching, 120-121 Collagen, 64, 71, 120 stretching capacity of, 120 Compliance, 2 Cryotherapy, 107-108

D Dancers, 55-59 flexibility applications for, 61-65 muscle stretching for, 56-59 hip adductors, 56 hip extensors, 57 splits, 58-59 Diabetes mellitus, 72, 109

Diagnosis and Treatmem of Movement lmpairmem Syndromes (Sahrmann),86 Diathermy. See Thermal diathermy Divers, 55-59 flexibility applications for, 61-65 muscle stretching for, 56-59 hip adductors, 56 hip extensors, 57 splits, 58-59 Dynamic flexibility, 5 Dynamic stretching, 12-15, 77 with barbells, 14 for lower limb muscles, 25, 27, 29, 31,33,35 adductors, 27 extensors, 25 flexors, 29 lateral rotators, 33 medial rotators, 31 plantar flexors, 35 muscle/fascia/tendon complex during, 124 for pectorals, 14 resistance in, 13 slow/static v., 13, 15 speed ranges for, 13 in sports. 13 for trunk muscles. 14,49,51,53 extensors, 49 lateral flexors, 51 rotations and, 14 rotators, 53 for upper limb muscles, 39. 41,43, 45

155

156

Index

Dynamic stretching (cont.) horizontal adductors, 41 shoulder extensors, 39 shoulder medial rotators, 43 wrist flexors, 45 E Elastin, 70, 116, 120 stretching capacity of, 120 Electromyography (EMG), 116-118 Electrotherapy, 108 NMES,108 EMG. See Electromyography End feel, 4, 105 Exercise, 69-79 flexibility and, 69-79 isotonic training and, 76 resistance training and, 76 strength-training and, 76 in physical therapy, 97 solo, for 3S, 135-137 for specific sports and activities, 138-139 warm-ups, 74

F Fatigue, 70 Females, flexibility of, 70 Figure skaters, 55-59 flexibility applications for, 61-65 muscle stretching for, 56-59 hip adductors, 56 hip extensors, 57 splits, 58-59 stretching for, 56-59 FlexAbility LE 1000, 16, 116 research studies on, 133-135 Flexibility. See also Dynamic flexibility; Flexibility programs; Physical therapy; Stretching acupuncture for, 101-103 clinical studies for, 102-103 neuromuscular spindles and, 101 treatment goals for, 101 age and, 69-70 anatomic constraints to, 71-72 muscular hypertrophy as, 71

clinical concepts for, 97-110 muscle imbalance correction as, 99-100 TCM as, 100-104 techniques in, 104-109 compliance and, 2 components of, 4-5 definitions of, 1-6 ability, 2-3 one-word, 2 problems with, 3 range-of-motion, 2-3 disease a factor for, 72 arthritis, 72 diabetes mellitus, 72, 109 hemophilia, 72 as dispositional property, 3-4 dynamic motion and, 5 Elastin and, 70 electrotherapy for, 108 exercise and, 69-79 isotonic training as, 76 resistance training as, 76 strength-training as, 76 external forces and, 5 factors for, 4 fatigue and, 70 functional, 98-99 fundamental terms for, 128-130 GAG and, 72 gender and, 70 females, 70 males, 70 GTOs and, 71, 113 injury as factor for, 72-73 stretching and, 72-73 for joint groups, 3-5 massage and, 76, 104 measures of, 5 mobility and, 2 as physical property, 3 posture and, 73 range-of-motion and, 97-98 as "reciprocal counterpart" to stiffness, 2 Relaxin hormone and, 70 as restorative, 4 sex and, 70 in soft tissues, 4,104-106

Index manipulation of, 104 mobilization of, 105-106 traction in, 106 thermal agents for, 106-108 cryotherapy, 107-108 thermotherapy, 106-107 time of day as factor for, 70 tissue temperature and, 74 thermal diathermy and, 74 thermal ultrasound and, 74 warm-ups and, 74, 76 training principles for, 79 overload as, 79 retrogression as, 79 specificity as, 62, 79 yoga for, 5 Flexibility programs, 61-65 benefits of, 62-63 dance applications with, 61-65 fitness applications of, 61-65 principle of specificity for, 62, 79 sports applications of, 61-65 therapeutic value of, 92-93 G GAG. See Glucosaminoglycan Gender, 70 flexibility and, 70 females, 70 males, 70 Glucosaminoglycan (GAG), 72 Golf, 92 Golgi tendon organs (GTOs), 71,113, 115 Goniometry,5-6 GTOs. See Golgi tendon organs Gymnasts, 55-59 flexibility applications for, 61-65 muscle stretching for, 56-59 hip adductors, 56 hip extensors, 57 splits, 58-59 H

Hatha yoga, 11-12 Hemophilia, 72 Hormones, 70 Relaxin, 70

157

Hypomobility, 72, 109 diabetes mellitus and, 72, 109 hemophilia and, 72 I

Injuries, 72-73, 84-86 Achilles tendinopathy, 72 flexibility and, 72 under PNF, 15 stretching and, 72-73, 84-86 as cause of, 84-87 lower risk levels from, 72-73, 88-90 stretch tolerance hypothesis and, 84-85 Isometrics, 18-19 PMVIC and, 18-19 in 3S, 18-19 Isotonic training, 76

J "Joint play," 4 Joint play technique, 105 Joints, 3-5, 71-72 anatomic constraints for, 71 "end feel" for, 4 functions of, 4 groups of, flexibility of, 3-5 hypomobility for, 72 "joint play," 4 range-of-motion for, 2 stability of, 4 K

Kinesiologists, 5 M Males, flexibility of, 70 Massage, 76, 104 Meditation, 12 Men. See Males, flexibility of Mobility, 2 Muscle/fascia/tendon complex, during stretching, 114-125 biomechanical explanations for, 119-120 components of, 114-115

158

Index

Muscle/fascia/tendon complex, during stretching (cont.) during dynamic stretching, 123 Elastin in, 70, 116, 120 stretching capacity of, 120 fascia hypothesis and, 124 GTOs in, 71, 113, 115 model of, 114 neural adaptations for, 120-125 sarcomere in, 116 in slow/static stretching, 122 strength training V., 121 3S and, mechanisms of, 115-119, 124-125 EMGs for, 116-118 tissue adaptations during, 120-125 Muscles, stretching for. See also Dynamic stretching; Muscle/ fascia/tendon complex, during stretching; Reversal of antagonists; Slow/static stretching; Yoga anatomic constraints for, 71 for athletes, 55-59 damage from, 86-87 imbalance correction and, 99-100 for lower limbs, 23-35 adductors, 26-28 extensors, 24-25 flexors, 28-29 lateral rotators, 32-33 medial rotators, 30-31 plantar flexors, 34-35 for musculotendinous units, 73 for neck, 54 neuromuscular spindles and, 101 for pectorals, 14 for quadriceps, 12 for trunk, 47-53 extensors, 48-49 lateral flexors, 50-51 rotators, 52-53 for upper limbs, 37-45 horizontal adductors, 40-41 shoulder extensors, 38-39 shoulder medial rotators, 42-43 wrist flexors, 44-45 Musculotendinous units, 73 Neck,54

Neuromuscular electrical stimulation (NMES),108 Neuromuscular spindles, 101 NMES. See Neuromuscular electrical stimulation

o Overload, 79 p

Partners, for stretching, 21-35 for lower limb muscles, 23-35 adductors, 26 extensors, 24 flexors, 28 lateral rotators, 32 medial rotators, 30 plantar flexors, 34 passive, 21-22 Pectoral muscles, 14 Perceived maximum voluntary isometric contractions (PMVIC),18-19 Physical therapy, 76, 78, 97-99, 104-106 electrotherapy in, 108 end feel technique in, 4, 105 exercise in, 97 joint play technique in, 105 massage in, 76, 104 of soft tissues, 104-106 manipulation in, 104 mobilization in, 105-106 traction in, 106 thermal agents in, 106-108 cryotherapy, 107-108 thermotherapy, 106-107 3S in, 78,98-99 individuality in, 98-99 ultrasound for, 108-109 PMVIC. See Perceived maximum voluntary isometric contractions PNF. See Proprioceptive neuromuscular facilitation Pope, RP., 88 Posture, 73 Potential range-of-motion, 2-3 Principle of specificity, 62, 79

Index Proprioceptive neuromuscular facilitation (PNF), 11, 15-19. See also Reversal of antagonists injury risks with. 15 PMVIC as part of, 18-19 variations of, 15-16 contract-relax, 15 hold-relax, 15 slow-reversal-hold-relax, 15

Q Quadriceps, 12

R Range-of-motion, 2-3. See also Flexibility acupuncture and, 101-103 anatomic constraints to, 7]-72 flexibility and, 97-98 in golf. 92 for joints, 2 for neck, 54 potential, 2-3 during sprint running, 91 in swimming, 91-92 in weightlifting, 92 Relaxin, 70 Resistance, 13 Resistance training, 76 Retrogression, 79 Reversal of antagonists (3S) stretching, 15-21,77, 115-119 accessory devices for, 17 anatomy of, 131-132 beginning positions for, 18 concentric contraction and, 19-20 flexibility programs for, 19 exercise prescriptions for, 18 FlexAbility LE 1000 for, 17 isometric contractionlrelease as part uf. 18-19 flexibility programs for, 19 for lower limb muscles, 24, 26, 28, 30,32,34 adductors, 26 extensors, 24 flexors, 28 lateral rotators, 32

159

medial rotators, 30 plantar flexors, 34 machines for, 135-137 muscle/fascia/tendon complex and, physical effects on. 115-119, 124 EMGs for, J16-lJ8 partners during, 17 in physical therapy, 78, 98-99 individuality as part of, 98-99 reps/sets per session for, 20-2] solo exercises for, 135-137 for trunk muscles, 48, 50, 52 extensors, 48 lateral flexors, 50 rotators, 52 for upper limb muscles, 38, 40, 42, 44 horizontal adductors, 40 shoulder extensors. 38 shoulder medial rotators, 42 wrist flexors, 44 viscoelastic changes from. 87 S Sahrmann, S.A., 86-87 Sarcomere, 116

Scientific Teaching for Sporr, 16 Sex. See Gender Shrier, lan, 84-85 stretch tolerance hypothesis of, 84-85 Slow/static stretching, 5. 12-13,77 applications of, 12 dynamic v., 13, 15 for lower limb muscles, 25, 27, 29, 31,33,35 adductors, 27 extensors, 25 flexors, 29 lateral rotators, 33 medial rotators, 31 plantar ncxurs, 35 muscle/fascia/tendon complex during, 124 for quadriceps, 12 for trunk muscles, 49, 51, 53 extensors, 49 lateral flexors, 5 I rotators. 53

160

Index

Slow/static stretching (cont.) for upper limb muscles, 39, 41, 43, 45 horizontal adductors, 41 shoulder extensors, 39 shoulder medial rotators, 43 wrist flexors, 45 Soft tissues. See Tissues Splits, 58-59 Sports and activities. See also Divers; Figure skaters; Gymnasts dynamic stretching in, 13 flexibility applications for, 61-65 potential benefits of, 63 golf,92 isotonic training for, 76 recommended exercises for, 138-139 resistance training for, 76 sprint running, 91 strength-training for, 76 swimming, 91-92 weightlifting, 92 Sprint running, 91 Stiffness, 2 Strength training, 64 Collagen increase from, 64 muscle/fascia/tendon stretching v., 121-122 Strength-training, 76 Stretching, 5,11-21. See also Dynamic stretching; Muscle/fascia/ tendon complex, during stretching; Proprioceptive neuromuscular facilitation; Reversal of antagonists stretching; Slow/static stretching acute, 85 for athletes, 55-59 hip adductors, 56 hip extensors, 57 splits, 58-59 chronic, 120-121 contraindications for, 21,109-110 dance applications of, 61--65 dynamic, 12-15,77 with barbells, 14 for lower limb muscles, 25, 27, 29,31,33,35

for pectorals, 14 resistance in, 13 slow/static v., 13, 15 speed ranges for, 13 in sports, 13 for trunk muscles, 14,49,51,53 for upper limb muscles, 39, 41, 43,45 fitness applications of, 61--65 injury and, 72-73, 84-86 as cause of, 84-86 decreases in from, 72-73, 88-90 literary reviews about, 83-84 for muscles, 12, 14,23-35 for lower limbs, 23-35 for neck, 54 pectorals, 14 quadriceps, 12 for trunk, 47-53 for upper limbs, 37-45 myths about, 83-94 injuries and, 84-85, 88-90 performance improvement as, 90-92 similarity of effects as, 93-94 therapeutic value as, 92-93 tissue damage as, 86-87 with passive partners, 17,21-22 PNF, 11, 15-19,77 injury risks with, 15 PMVIC as part of, 18-19 variations of, 15-16 recommendations for, 77-79 slow/static, 5, 12-13,77 applications of, 12 dynamic v., 13, 15 for lower limb muscles, 25, 27, 29,31,33,35 for quadriceps, 12 for trunk muscles, 49, 51, 53 for upper limb muscles, 39, 41, 43,45 stretch tolerance hypothesis, 84-85 Tai Chi as, 103 technique comparisons, 15 3S, 15-21, 77 accessory devices for, 17 beginning positions for, 18

Index concentric contraction and, 19-20 exercise prescriptions for, 18 isometric contraction/release as part of, 18-19 for lower limb muscles, 24, 26, 28,30,32,34 partners during, 17 reps/sets per session for, 20-21 for trunk muscles, 48, 50, 52 for upper limb muscles, 38, 40, 42,44 viscoelastic changes from, 87 warm-up exercises for, 74 stretching partners. See partners, for stretching Stretch tolerance hypothesis, 84-85 injuries in, 84-85 Swimming, 91-92 T Tae Kwon 00,64 Tai Chi, 103 TCM. See Traditional Chinese medicine Temperature, for tissues, 74 in physical therapy, 106-108 thermal diathermy and, 74 thermal ultrasound and, 74 warm-ups and, 74 Tendonitis. See Achilles tendinopathy Therapy. See Physical therapy Thermal diathermy, 74 Thermal ultrasound, 74 Thermotherapy, 106-108 3S. See Reversal of antagonists Tissues, 4, 74, 86-87, 104-106. See also Muscle/fascia/tendon complex, during stretching damage to, from stretching, 86-87 Elastin in, 70 flexibility of, 4, 104-106 manipulation in, 104 mobilization in, 105-106 traction in, 106 during muscle/fascia/tendon complex stretching, 120-124

161

temperature for, 74 thermal diathermy and, 74 thermal ultrasound and, 74 warm-ups and, 74 Traction, 106 Traditional Chinese medicine (TCM), 100-104. See also Yoga acupuncture in, 101-103 clinical studies for, 102-103 inverted-U in, 98 neuromuscular spindles, 101 range-of-motion and, 101-102 Tai Chi as, 103 yoga as, 5, 11-12, 103 breathing protocols for, 11-12 Hatha,11 for lower limb muscles, 25, 27, 29,31,33 meditation with, 12 relaxation and, 12 for trunk muscles, 49, 51, 53 for upper limb muscles, 39,41, 43, 45 Trunk rotations, 14 U Ultrasound for physical therapy, 108-109 thermal, 74 W

Warm-ups, 74, 76 Weightlifting, 92 Women. See Females, flexibility of y

Yoga, 5, 11-12, 104 breathing protocols for, 11-12 flexibility and, 5 Hatha,11 for lower limb muscles, 25, 27, 29, 31,33 adductors, 27 extensors, 25 flexors, 29 lateral rotators, 33 medial rotators, 31 plantar flexors, 35 meditation with. 12

162

Index

Yoga (cont.) relaxation and, 12 for trunk muscles, 49, 51, 53 extensors, 49 lateral flexors, 51 rotators, 53

for upper limb muscles, 39, 41, 43, 45 horizontal adductors, 41 shoulder extensors, 39 shoulder medial rotators, 43 wrist flexors, 45