by Chan Suk Ping. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (leaves 105-119). / Abstract also in Chinese. / Acknowledgments --- p.i / Abstract --- p.ii / List of Tables --- p.ix / List of Figures --- p.xii / Abbreviation --- p.xiv / Chapter CHAPTER ONE --- INTRODUCTION / Chapter 1.1 --- Background --- p.1 / Chapter 1.2 --- The Research Problem --- p.7 / Chapter 1.2.1 --- Purpose of The Study --- p.7 / Chapter 1.2.2 --- Variables and Definition of Terms --- p.8 / Chapter 1.2.3 --- Hypotheses --- p.10 / Chapter 1.2.4 --- Significance of The Study --- p.11 / Chapter CHAPTER TWO --- REVIEW OF LITERATURE / Chapter 2.1 --- Benefits and Potential Disadvantages of Stretching --- p.12 / Chapter 2.1.1 --- Benefits of Stretching --- p.12 / Chapter (a) --- Muscle Relaxation --- p.12 / Chapter (b) --- Performance Enhancement --- p.14 / Chapter (c) --- Prevention of Injury --- p.17 / Chapter (d) --- Increase of Range of Motion --- p.19 / Chapter (e) --- Prevention of Muscle Soreness --- p.20 / Chapter 2.1.2 --- The Potential Disadvantages of Stretching --- p.20 / Chapter 2.2 --- Limiting Factors of Flexibility --- p.22 / Chapter 2.2.1 --- Muscle --- p.22 / Chapter (a) --- Histologic Components of Muscle --- p.22 / Chapter (b) --- Muscular Elongation --- p.23 / Chapter (c) --- The Effects of Immobilization --- p.23 / Chapter 2.2.2 --- Connective Tissue --- p.24 / Chapter (a) --- Collagen --- p.25 / Chapter (b) --- Elastic Tissue --- p.27 / Chapter (c) --- Tissue Composed of Connective Tissue --- p.27 / Chapter 2.2.3 --- The Mechanical Properties of Soft Tissue --- p.30 / Chapter 2.2.4 --- "Age, Gender, Physical Activity and Temperature" --- p.33 / Chapter 2.3 --- Neurophysiology of Stretching --- p.34 / Chapter 2.3.1 --- Muscle Spindles and Golgi Tendon Organs --- p.34 / Chapter (a) --- Structure and Role of Muscle Spindle --- p.35 / Chapter (b) --- Structure and Role of Golgi Tendon Organs --- p.38 / Chapter (c) --- Parallel and Series End Organs --- p.38 / Chapter 2.3.2 --- Electromyography --- p.39 / Chapter 2.4 --- Hamstrings --- p.43 / Chapter 2.4.1 --- Functions of Hamstrings --- p.43 / Chapter 2.4.2 --- Limited Range of Motion in Hamstrings --- p.45 / Chapter 2.4.3 --- Measurement of Hamstrings Flexibility --- p.46 / Chapter 2.5 --- Stretching Protocol --- p.50 / Chapter 2.5.1 --- Modes of Stretching --- p.50 / Chapter 2.5.2 --- Intensity of Stretching --- p.53 / Chapter CHAPTER THREE --- METHOD / Chapter 3.1 --- Subjects --- p.55 / Chapter 3.2 --- Instrumentation --- p.57 / Chapter 3.3 --- Procedure --- p.60 / Chapter 3.4 --- Reliability Study --- p.69 / Chapter 3.5 --- Data Analysis --- p.70 / Chapter CHAPTER FOUR --- RESULTS / Chapter 4.1 --- Reliability Study --- p.72 / Chapter 4.2 --- Experimental Study --- p.73 / Chapter 4.2.1 --- Range of Motion of Pre-Test and Post-Test --- p.74 / Chapter 4.2.2 --- Passive Resistance of Pre-Test and Post-Test --- p.75 / Chapter 4.2.3 --- Subjective Rating of Pre-Test and Post-Test --- p.76 / Chapter 4.2.4 --- Myoelectric Activities of Hamstrings of Pre-Test and Post-Test --- p.76 / Chapter 4.2.5 --- Hamstrings Performance of Pre-Test and Post-Test --- p.79 / Chapter 4.2.6 --- Range of Motion Difference among Trained and Untrained Groups --- p.81 / Chapter 4.2.7 --- Passive Resistance of Hamstrings Difference among Trained and Untrained Groups --- p.82 / Chapter 4.2.8 --- Subjective Rating of Perceived Stretch Difference among Trained and Untrained Groups --- p.82 / Chapter 4.2.9 --- Myoelectric Activities of Hamstrings Difference among Trained and Untrained Groups --- p.83 / Chapter 4.3.0 --- Performance of Hamstrings Difference among Trained and Untrained Groups --- p.83 / Chapter CHAPTER FIVE --- DISCUSSION / Chapter 5.1 --- Hamstrings Flexibility Analysis --- p.92 / Chapter 5.2 --- Hamstrings Passive Resistance Analysis --- p.94 / Chapter 5.3 --- Rating of Perceived Stretch Analysis --- p.97 / Chapter 5.4 --- Hamstrings Myoelectric Activities Analysis --- p.98 / Chapter 5.5 --- Hamstrings Performance Analysis --- p.100 / Chapter 5.6 --- Limitations and Suggestions --- p.102 / Chapter 5.7 --- Conclusions --- p.103 / REFERENCES --- p.105 / APPENDIX / Appendix A. Informed Consent / Appendix B. Personal Particulars and Past Medical History Screening Sheet / Appendix C. Perceived Stretch Rating Scale / Appendix D. Record Sheet

OBJECTIVE: Human myometrium contains both beta1-adrenergic and beta2-adrenergic receptors. This study was designed to assess the importance of each beta-adrenergic receptor subtype in relaxation of human myometrial muscle strips. STUDY DESIGN: Radioligand binding studies were used to establish the presence of each beta-adrenergic receptor subtype, whereas highly selective beta1-antagonists and beta2-antagonists were used to assess the contribution of beta-adrenergic receptor subtypes to myometrial relaxation after exposure to (-)-isoproterenol. RESULTS: Membranes prepared from myometrium contained 82% +/- 4% beta2-adrenergic receptors. After contraction produced by exposure to potassium chloride (35 mmol/L), isoproterenol produced relaxation with half maximal effect at 0.02 micromol/L and a maximal relaxation of 52% +/- 3%. Beta1-antagonist CGP-20712A had no significant effect, whereas beta2-antagonist ICI-118551 produced a characteristic rightward shift of the isoproterenol concentration-relaxation relationship. CONCLUSIONS: Although both beta1-adrenergic receptors and beta2-adrenergic receptors are present in human myometrial tissue at term, relaxation by nonselective beta-agonist isoproterenol is mediated exclusively by beta2-adrenergic receptors.