Selected Physiological Characteristics of Elite Rowers Measured in the Laboratory and Field and Their Relationship with Performance
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SELECTED PHYSIOLOGICAL CHARACTERISTICS OF ELITE ROWERS MEASURED IN THE LABORATORY AND FIELD AND THEIR RELATIONSHIP WITH PERFORMANCE by GILES D. WARRINGTON A thesis submitted to the University of Surrey for the degree of DOCTOR OF PHILOSOPHY Robens Institute University of Surrey Guildford Surrey GU2 5XH England July 1998 ProQuest Number: 27750273 All rights reserved INFORMATION TO ALL USERS The quality of this reproduction is dependent on the quality of the copy submitted. in the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted. Also, if material had to be removed, a note will indicate the deletion. uest ProQuest27750273 Published by ProQuest LLC(2019). Copyright of the Dissertation is held by the Author. Ail Rights Reserved. This work is protected against unauthorized copying under Title 17, United States Code Microform Edition © ProQuest LLC. ProQuest LLC 789 East Eisenhower Parkway P.O. Box 1346 Ann Arbor, Ml 48106 - 1346 ABSTRACT In the present study, a number of physiological variables were measured on members of the Great Britain heavyweight rowing squad in the laboratory, field and also during altitude training. The main purposes of the study were to determine which of these physiological variables were important determinants of success in rowing and to evaluate the effects of a specific phase of training on these variables. Additionally, the study sought to assess the effectiveness of different modes of training by monitoring the physiological responses and adaptations to a period of altitude training and evaluating their impact on aerobic work capacity on return to sea level. Of the 22 descriptive and physiological variables measured to determine their relationship with rowing performance, maximal oxygen uptake (FO2 max) expressed in absolute terms (Imin^) was found to be the best single predictor of rowing performance for the 6 minute (DIST6) and 2500 metre (T2500) performance tests used. Although a number of other physiological variables were found to be significantly related to rowing performance, their inclusion added little to a predictor model of performance. Analysis of the physiological responses to a 3 month phase of training revealed significant improvements in rowing economy (P<0.01) and the exercise intensity attained at a fixed blood lactate concentration of 4 mmol l'^ (P<0.05). In contrast to these improvements in submaximal variables, no significant change was observed for FO2 max. Changes in the mean daily values for 10 physiological variables measured over 19 days of altitude training and were compared to pre-altitude values. The increase in haemoglobin (Hb) in response to training in a hypobaric environment appears to reflect an increase in haemoconcentration due to a reduction in plasma volume (PV) and to a lesser degree erythropoiesis. Additionally, it appears that those subjects with lower initial Hb levels experienced the greatest increase during altitude training. A significant rise in serum creatine kinase (CK) (P<0.01) and urea (P<0.01) were observed afi;er the period of acclimatisation, which tends to indicate that any increases were associated with a progressive elevation in training load, after this phase, rather than the hypoxic stimulusper se. On return to sea level, there was no significant (P>0.05) improvement in aerobic work capacity, as determined by a fall in submaximal blood lactate concentrations during prolonged exercise. DECLARATION The work presented in this thesis is entirely my own work and it has not been previously submitted to this or any other institute of higher education for this or any other academic award. Where use has been made of the work of other people, it has been acknowledged and is hilly referenced. Signed Date ACKNOWLEDGEMENTS Throughout the production of this study the author has been indebted to a number of people. Special acknowledgement goes to Professor Craig Sharp for his expert input during the early stages of the study and his continued support and friendship. Sincere thanks is extended to my former colleagues at the British Olympic Medical Centre for their assistance in the collection of data. My greatest debt is owed to my supervisors Professor Colin Boreham, Professor David Stubbs and Dr Mike Tipton for their valuable guidance, advice and encouragement throughout. Gratitude goes to Dr Kevin Hayes for his expertise and patients in explaining some of the more complex statistical procedures and to Donal O'Gorman for his technical advice and comment. This study would have remained an aspiration without the unwavering support of my friends and family over the last 6 years. Last and by no means least, I would like to extend my sincere thanks the coaches and members of the Great Britain rowing squad who participated as subjects in the study and who’s motivation, dedication and determination in the quest to achieve excellence in their chosen sport inspired my interest in rowing in the first place. Ill *DediMtco*t To love is human, to be loved is special IV GLOSSARY OF TERMS Critical Power A theoretical concept that presumes that there is a maximum power that an individual can maintain indefinitely. It is based on the observation that the duration for which high intensity exercise can be performed to the point of fatigue is inversely proportional to the power. 2,3-diphosphoglycerate (2,3-DPG) An inorganic phosphate compound which is produced within the red blood cells during glycolysis. It is bound to haemoglobin in the red blood cells and reduces the affinity of haemoglobin for oxygen, shifting the oxygen dissociation curve to the right thereby assisting the unloading of oxygen to the tissues. Erythropoietin (EPO) A glycoprotein which stimulates erythropoiesis by enhancing the mitotic frequency of erythroide precursors in the bone marrow. Fractional Utilisation The percentage of VO2 max utilised at any given submaximal work intensity. Haematocrit (Hct) The volume of red blood cells usually expressed as a percentage of total blood volume. Haemoblobin (Hb) The oxygen-transporting component of red blood cells. It consists of a large conjugated protein consisting of four polypeptide chains, each with a prosthetic haem group which contains ferrous iron, able to combine reversibly with oxygen. Maximal Oxygen Uptake (FO2 max) The maximal ability of an individual to take up, transport and utilise oxygen by the working muscles. Myoglobin An oxygen-binding protein in skeletal muscle. Oxygen Debt The amount of oxygen consumed during recovery from exercise above that which would be consumed at rest in the same period. Oxygen Deficit The difference between the total oxygen consumed during exercise and the total that would have been consumed had a steady rate of aerobic metabolism been reached at the start. Partial Pressure The pressure exerted by a single gas in a mixture of gases. It can be calculated by multiplying the total pressure of the mixture of gases within which the particular gas occurs, by the percentage of the total volume the gas occupies. Peak Power The peak work output that a rower can achieve during a maximal performance test on a rowing ergometer measured in watts. Polycythemia An increase in the total number of red blood cells per mm'^ of blood. Rowing Economy The steady state oxygen consumption for a standardised submaximal workload or fixed reference point. VI TABLE OF CONTENTS Page CHAPTER 1 INTRODUCTION 1. Background 1 2. Statement of the Problem 2 3. Purpose 2 4. Hypotheses 4 5. Delimitations 5 6. Limitations 6 CHAPTER 2 REVIEW OF LITERATURE 1. Introduction 7 2. Predictors of Performance 8 2.1. Maximal Oxygen Uptake 8 2.2. Blood Lactate Indices 11 2.3. Maximum Power 14 2.4. Critical Power 15 2.5. Submaximal Ventilatory Parameters 17 2.5.1. Economy 17 2.5.2. Fractional Utilisation 19 2.6. Anaerobic Capacity 22 3. Physiological Responses to Rowing Training 24 3.1. Maximal Aerobic Power 25 3.2. Blood Lactate 25 3.3. Other Submaximal Variables 26 3.4. Strength and Power 27 4. Altitude Training and Sea Level Performance 28 4.1. Haematological Changes 28 4.2. Oxygen Release and 2, 3-diphosphoglycerate (2,3-DPG) 31 4.3. Cardiac Output 34 4.4. Altitude Training and Skeletal Muscle Metabolism 35 4.4.1. Skeletal Muscle Capillaries 36 4.4.2. Skeletal Muscle Enzymes 37 4.4.3. Myoglobin 39 4.5. Substrate Utilisation 40 4.6. Muscle and Blood Buffering Capacity 41 4.7. Maximal Aerobic Power 42 4.8. Altitude Training and Sea Level Performance 43 4.9 Summary 46 CHAPTER 3 A Comparison of Selected Physiological Parameters as Predictors of Rowing Performance. MATERIALS AND METHODS 1. Introduction 48 2. Ethical Considerations 49 3. Subjects 49 4. Anthropometric Measurements 49 4.1. Body Mass and Stature 50 4.2. Body Composition 50 4.3. Breadths 52 4.3.1. Biacromial Breadth 52 4.3.2. Biiliac Breadth 52 4.3.3. Wrist Breadth 52 4.4. Circumferences 53 4.4.1. Thigh Circumference 5 3 4.4.2. Upper Arm Circumference 53 4.4.3. Forearm Circumference 5 4 5. Cardiorespiratory Evaluation 54 5.1. Ambient Conditions 5 4 5.2. Submaximal Discontinuous Incremental Test 54 5.3. Respiratory Analysis 56 5.4. Maximal Oxygen Uptake 57 5.5. Rowing Economy 57 5.6. Fractional Utilisation 58 5.7. Heart Rate Measurement 58 5.8. Blood Lactate Analysis 58 5.9. Determination of Fixed Blood Lactate Concentrations 60 6. Rowing Performance Tests 61 6.1. 6 Minute “All-Out” Test 61 6.2 2500 metre Test 62 7. Statistical Analysis 63 RESULTS 64 DISCUSSION 76 SUMMARY, CONCLUSIONS AND RECOMMENDATIONS 83 CHAPTER 4 An analysis of the variation in selected physiological parameters during a 3 month period of training. MATERIALS AND METHODS 1. Introduction 85 2. Ethical Considerations 86 3.