Optimizing Physical Performance During Fasting and Dietary Restriction : Implications for Athletes and Sports Medicine PDF
Preview Optimizing Physical Performance During Fasting and Dietary Restriction : Implications for Athletes and Sports Medicine
OPTIMIZING PHYSICAL PERFORMANCE DURING FASTING DIETARY AND RESTRICTION Implications for Athletes and Sports Medicine OPTIMIZING PHYSICAL PERFORMANCE DURING FASTING DIETARY AND RESTRICTION Implications for Athletes and Sports Medicine Ezdine Bouhlel University of Manouba, Tunisia Roy J Shephard University of Toronto, Canada Boca Raton London New York CRC Press is an imprint of the Taylor & Francis Group, an informa business CRC Press Taylor & Francis Group 6000 Broken Sound Parkway NW, Suite 300 Boca Raton, FL 33487-2742 © 2016 by Taylor & Francis Group, LLC CRC Press is an imprint of Taylor & Francis Group, an Informa business No claim to original U.S. Government works Version Date: 20150709 International Standard Book Number-13: 978-1-4987-2566-8 (eBook - PDF) This book contains information obtained from authentic and highly regarded sources. While all reasonable efforts have been made to publish reliable data and information, neither the author[s] nor the publisher can accept any legal responsibility or liability for any errors or omissions that may be made. The publishers wish to make clear that any views or opinions expressed in this book by individual editors, authors or contributors are personal to them and do not necessarily reflect the views/opinions of the publishers. The information or guidance contained in this book is intended for use by medical, scientific or health-care professionals and is provided strictly as a supplement to the medical or other professional’s own judgement, their knowledge of the patient’s medical history, relevant manufacturer’s instructions and the appropriate best practice guide- lines. Because of the rapid advances in medical science, any information or advice on dosages, procedures or diagnoses should be independently verified. The reader is strongly urged to consult the relevant national drug formulary and the drug companies’ and device or material manufacturers’ printed instructions, and their websites, before administering or utilizing any of the drugs, devices or materials mentioned in this book. This book does not indicate whether a particular treatment is appropriate or suitable for a particular individual. Ultimately it is the sole responsibility of the medical professional to make his or her own profes- sional judgements, so as to advise and treat patients appropriately. The authors and publishers have also attempted to trace the copyright holders of all material reproduced in this publication and apologize to copyright holders if permission to publish in this form has not been obtained. If any copyright material has not been acknowledged please write and let us know so we may rectify in any future reprint. Except as permitted under U.S. Copyright Law, no part of this book may be reprinted, reproduced, transmit- ted, or utilized in any form by any electronic, mechanical, or other means, now known or hereafter invented, including photocopying, microfilming, and recording, or in any information storage or retrieval system, without written permission from the publishers. For permission to photocopy or use material electronically from this work, please access www.copyright. com (http://www.copyright.com/) or contact the Copyright Clearance Center, Inc. (CCC), 222 Rosewood Drive, Danvers, MA 01923, 978-750-8400. CCC is a not-for-profit organization that provides licenses and registration for a variety of users. For organizations that have been granted a photocopy license by the CCC, a separate system of payment has been arranged. Trademark Notice: Product or corporate names may be trademarks or registered trademarks, and are used only for identification and explanation without intent to infringe. Visit the Taylor & Francis Web site at http://www.taylorandfrancis.com and the CRC Press Web site at http://www.crcpress.com Contents Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xv Contributors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xvii 1 Introduction: Characteristics of Fasting . . . . . . . . . . . 1 Ezdine Bouhlel and Roy J Shephard Learning Objectives 1 Total Fasting and Dietary Restrictions 1 Intermittent Fasting during Ramadan 3 Overall Requirements for Observant Muslims 4 Fasting 4 Implications for Sedentary Individuals 5 Implications for Athletes 5 Fasting in the Greek Orthodox Church 7 Daniel Fasting 8 Focus of the Present Text 8 Conclusions 8 Key Terms 9 Questions for Discussion 10 References 10 Further Reading 11 2 Changes of Body Mass and Energy Balance during Fasting and Dietary Restriction . . . . . . . . . . . . . . . . 13 Ezdine Bouhlel and Roy J Shephard Learning Objectives 13 Introduction 13 Energy Balance 14 Energy Intake 14 Energy Expenditure 16 Basal Metabolic Rate 16 Physical Exercise 16 Other Sources of Energy Expenditure 17 Body Stores of Energy and Fluids 17 Carbohydrate 17 Fat 18 v vi Contents Protein 18 Fluid 19 Issue of Metabolic Ketosis 19 Classical View of Metabolic Ketosis 19 Impact of Circumpolar Research 19 Laboratory Trials of a Ketotic Diet 20 Conclusion 21 Severe Food Deprivation 21 Minnesota Starvation Study 22 Other Studies of Severe Food Deprivation 23 Prolonged Moderate Food Restriction 23 Dieting Alone 23 Dieting Plus Exercise 24 Vegan-Type Dietary Restrictions 25 Restrictions of Fluid Intake 25 Fluid Needs 26 Aerobic Performance 26 Muscular Performance 27 Anaerobic Power and Capacity 30 Thermoregulation 30 Cerebral Function 30 Other Adverse Effects 31 Time Needed for Rehydration 31 Intermittent (Ramadan) Fasting 31 Sedentary Subjects 31 Athletic Individuals 33 Total Fasting 35 Short-Term Fasting (12–36 hours) 35 Medium-Term Fasting (3–10 days) 38 Dietary Guidelines 39 Other Practical Implications 39 Conclusions 40 Key Terms 41 Questions for Discussion 42 References 42 Further Reading 52 3 Carbohydrate Metabolism and Fasting . . . . . . . . . . . 53 Ezdine Bouhlel and Roy J Shephard Learning Objectives 53 Nature of Carbohydrates and Normal Daily Requirements 53 Contents vii Classification of Carbohydrates 53 Monosaccharides 54 Disaccharides 54 Polysaccharides 54 Carbohydrate Stores and Physical Performance 54 Hormonal Mechanisms Regulating Anabolic and Catabolic Activities 55 Effects of Exercise Intensity and Duration on Carbohydrate Oxidation 56 Impact of Carbohydrate Supplements upon Physical Performance 56 Prior to Exercise 57 During Exercise 57 Effect of Fasting and/or Dietary Restrictions on Carbohydrate Metabolism 58 Impact of Ramadan Observance on Carbohydrate Intake and Blood Glucose 60 Implications for Athletic Performance 62 Conclusions 62 Key Terms 63 Questions for Discussion 64 References 64 Further Reading 67 4 Mobilization and Utilization of Lipids during Dietary Restriction Conditions . . . . . . . . . . . . . . . . . . . . . . 69 Ezdine Bouhlel and Roy J Shephard Learning Objectives 69 Fat Metabolism under Non-Fasting Conditions 70 Characteristics and Functions of Adipose Tissue 70 Regulation of Lipolysis 71 Factors Limiting Lipolysis 71 Transport of Long-Chained Fatty Acids into the Mitochondria 72 Metabolism of Fat at Rest 73 Metabolism of Fat during Exercise 74 Determination of the Crossover Point 75 Effect of Exercise Intensity 75 Low-Intensity Exercise 76 Moderate-Intensity Exercise 76 High-Intensity Exercise 76 viii Contents Effect of Exercise Duration 77 Effects of Endurance Training and Fitness Level 77 General Effects of Fasting upon Fat Metabolism 77 Total Fasting 77 Severe Dietary Restriction 79 Moderate Dietary Restriction 79 Ramadan Observance 79 Effects of Ramadan Observance upon Fat Metabolism in Athletes 81 Resting Conditions 81 During Exercise 81 Practical Applications 83 Areas Requiring Further Research 84 Conclusions 85 Key Terms 85 Questions for Discussion 88 References 88 Further Reading 92 5 Protein Metabolism during Dietary Restriction . . . . . . 93 Roy J Shephard Learning Objectives 93 Normal Protein Needs of the Body 93 Nutritional Recommendations 93 Nutritional Deficiency 94 Dietary Timing 94 Mechanisms Regulating Anabolic and Catabolic Activity 95 Hormonal Regulators 95 Training Response 96 Energy Deficiency during Exercise 96 Severe Dietary Restriction 96 Regulation during Ramadan Observance 96 Prolonged Energy Deficit 97 Dietary Restrictions, Protein Intake and Catabolism 97 Dietary Composition during Prolonged Dieting 97 Dietary Options during Ramadan Observance 98 Determining Dietary Composition 98 Empirical Data for Ramadan 98 Sedentary Subjects 101 Athletes 101 Changes in Plasma Amino Acid and Protein Concentrations 102 Contents ix Changes in Serum of Urea and Uric Acid 103 Changes in Blood Glucose 103 Changes in Body Composition with Dietary Restriction 103 Sedentary Subjects 103 Athletes 106 Practical Implications 106 Conclusions 108 Key Terms 108 Questions for Discussion 111 References 111 Further Reading 116 6 Hydration and Fluid Restriction in Athletes . . . . . . . . 117 Roy J Shephard Learning Objectives 117 Introduction 117 Normal Regulation of Fluid Balance in Human Subjects 118 Methods of Assessing Dehydration 119 Body Mass 119 Haemoglobin and Haematocrit 120 Serum Sodium Concentrations 120 Urinary Volumes and Specific Gravity 121 Bioimpedance Data 121 Effects of Water Deprivation 121 Effects of Repeated Moderate Fluid Restriction in Sedentary Individuals 122 Body Mass 124 Haemoglobin and Haematocrit 124 Serum Biochemistry 124 Urinary Volumes and Fluid Balance 125 Conclusions 125 Effects of Intermittent Fluid Restriction in Athletes 125 Body Mass 127 Haemoglobin and Haematocrit 127 Serum Biochemistry and Bioimpedance 128 Urinary Volumes and Specific Gravity 128 Practical Implications for the Muslim Athlete 129 Other Patterns of Fluid Depletion in Athletes 129 Conclusions 130 Key Terms 130 Questions for Discussion 131 References 132 Further Reading 134 x Contents 7 Changes in Hormone Levels and Circadian Rhythms during Fasting . . . . . . . . . . . . . . . . . . . . . . . . . . . 135 Ezdine Bouhlel, Zouhair Tabka and Roy J Shephard Learning Objectives 135 Introduction 135 Hormonal Adaptations to Exercise and Training 136 Insulin 136 Growth Hormone 137 Cortisol 138 Catecholamines 138 Glucagon 138 Thyroid Hormones 138 Sex Hormones 139 Antidiuretic Hormone and Aldosterone 139 Training Effects 139 Metabolic and Hormonal Responses to Fasting 140 Cortisol 143 Sex Hormones 143 Catecholamines 143 Protein Metabolism 143 Hormonal Responses to the Intermittent Fasting of Ramadan 144 Melatonin 144 Catecholamines and Thyroid Hormones 144 Cortisol and ACTH 146 Leptin and Adiponectin 147 Sex Hormones 147 Changes in Exercise Hormonal Responses during Ramadan Observance 147 Ramadan Observance, Sleep Patterns and Circadian Rhythms 148 Sleep Duration 149 Sedentary Subjects 150 Athletes 150 Sleep Quality 150 Circadian Rhythms 151 Rhythms of Body Temperature and Metabolism 151 Circadian Rhythms of Body Hormones 151 Circadian Rhythms of Physical Performance 152 Vigilance and Psychomotor Performance 152 Practical Implications 152 Conclusions 153 Key Terms 153
The list of books you might like
