Nutrtion Work
Heather Hedrick Fink, MS, RD, CSSD Owner Nutrition and Wellness Solutions, LLC Indianapolis, Indiana
Alan E. Mikesky, PhD, FACSM Professor Emeritus School of Physical Education and Tourism Management Indiana University-Purdue University Indianapolis Indianapolis, Indiana
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Library of Congress Cataloging-in-Publication Data Names: Fink, Heather Hedrick, author. | Mikesky, Alan E., author. Title: Practical applications in sports nutrition / Heather Hedrick Fink, Alan E. Mikesky. Description: Fifth edition. | Burlington, Massachusetts : Jones & Bartlett Learning, [2018] | Includes bibliographical references and index. Identifiers: LCCN 2016048145 | ISBN 9781284101393 (pbk.) Subjects: | MESH: Sports Nutritional Physiological Phenomena | Sports–physiology | Exercise–physiology | Sports Nutritional Sciences Classification: LCC TX361.A8 | NLM QT 263 | DDC 613.2024796–dc23 LC record available at https://lccn.loc.gov/2016048145
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BRIEF CONTENTS SECTION 1 The Basics of Sports Nutrition . . . . . . . . . . . . . . . . . . . . . . . . . 1 CHAPTER 1 Introduction to Sports Nutrition . . . . . . . . . . . . . . . . . . . . . . . 3 CHAPTER 2 Nutrients: Ingestion to Energy Metabolism . . . . . . . . . . . .23 CHAPTER 3 Carbohydrates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .59 CHAPTER 4 Fats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .91 CHAPTER 5 Proteins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116 CHAPTER 6 Vitamins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141 CHAPTER 7 Minerals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178 CHAPTER 8 Water . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 210 CHAPTER 9 Nutritional Ergogenics . . . . . . . . . . . . . . . . . . . . . . . . . . . . 239
SECTION 2 The Practical Application of Sports Nutrition . . . . . . . . 261 CHAPTER 10 Nutrition Consultation with Athletes . . . . . . . . . . . . . . . 263 CHAPTER 11 Weight Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 291 CHAPTER 12 Endurance and Ultra-Endurance Athletes . . . . . . . . . . . 330 CHAPTER 13 Strength/Power Athletes . . . . . . . . . . . . . . . . . . . . . . . . . . . 364 CHAPTER 14 Team Sport Athletes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 392 CHAPTER 15 Special Populations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 420 CHAPTER 16 Jobs in Sports Nutrition . . . . . . . . . . . . . . . . . . . . . . . . . . . 455 APPENDIX A You Are the Nutrition Coach – Answers . . . . . . . . . . . . . . 465 APPENDIX B The Gastrointestinal Tract . . . . . . . . . . . . . . . . . . . . . . . . . 471 APPENDIX C Major Metabolic Pathways . . . . . . . . . . . . . . . . . . . . . . . . . 474 APPENDIX D Calculations and Conversations . . . . . . . . . . . . . . . . . . . . 480 APPENDIX E Growth and Body Mass Index Charts . . . . . . . . . . . . . . . . 483 APPENDIX F Dietary Reference Intakes . . . . . . . . . . . . . . . . . . . . . . . . . 488
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CONTENTS
Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .xvi How to Use This Book . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xviii About the Authors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .xxiii Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xxiv
SECTION 1 The Basics of Sports Nutrition . . . . . . . . . . . . . . . . . . . . . . . . . 1 CHAPTER 1 Introduction to Sports Nutrition . . . . . . . . . . . . . . . . . . . . . . . 3
What is sports nutrition? 4 Why study sports nutrition? 4 What are the basic nutrients? 4
What are carbohydrates? 5 What are proteins? 5 What are fats? 5 What are vitamins? 5 What are minerals? 5 What is water? 6
How does the body produce energy? 6 What are the dietary reference intakes? 6 What are enriched and fortified foods? 7 What are the basic nutrition guidelines? 7
What are the Dietary Guidelines for Americans? 7 What is the MyPlate food guidance system? 9
How should athletes interpret the information on food labels? 11 Who created the food label regulations? 11 How can the ingredient list be useful to athletes? 11 How can the nutrition facts panel be useful to athletes? 12 How can the percent daily value be useful to athletes? 14 How can nutrient content claims be useful to athletes? 15 How can health claims be useful to athletes? 16
What are the factors to consider when developing an individualized sports nutrition plan for athletes? 17
Why should a sports nutrition plan consider an athlete’s health history? 18 Why should a sports nutrition plan consider a sport’s bioenergetics and logistics? 19 Why should a sports nutrition plan consider an athlete’s total
weekly training and competition time? 19 Why should a sports nutrition plan consider an athlete’s living
arrangements, access to food, and travel schedule? 19 How can sports nutrition knowledge be converted into practical applications? 20 Key Points of Chapter 21 Study Questions 21 References 22
CHAPTER 2 Nutrients: Ingestion to Energy Metabolism . . . . . . . . . . . .23 What happens to nutrients after they are ingested? 24
What are the functions of the various parts of the digestive system? 24
Contents v
How are carbohydrates digested, absorbed, transported, and assimilated in the body? 27
What happens to carbohydrates once they are put into the mouth? 27 How are the simple sugars absorbed into the intestinal wall? 29 What happens to carbohydrates once they make it into the blood? 31 What happens to carbohydrates once they make it to the cells of the body? 31
How are fats digested, absorbed, transported, and assimilated in the body? 31 What happens to fats once they are put into the mouth? 34 What happens to the fats once they are absorbed? 34 What happens to fats once they make it to the cells? 35
How are proteins digested, absorbed, transported, and assimilated in the body? 35 What happens to proteins once they are put into the mouth? 35 How are proteins absorbed into the intestinal wall? 37 What happens to amino acids once they make it to the bloodstream? 38 What happens to amino acids once they make it to the cells of the body? 39
How are minerals, vitamins, and water absorbed and transported in the body? 40 What is energy metabolism, and why is it important? 41 What is energy? 41 What is the human body’s source of chemical energy? 42 How do cells make ATP? 44 What are the three energy systems? 44
What are the characteristics of the phosphagen system? 46 What are the characteristics of the anaerobic and aerobic energy systems? 47
How do the energy systems work together to supply ATP during sport performance? 47
What metabolic pathways are involved with the energy systems? 49 Key Points of Chapter 56 Study Questions 57 References 58
CHAPTER 3 Carbohydrates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .59 What’s the big deal about carbohydrates? 60 What are carbohydrates? 60 How are carbohydrates classified? 61
What are simple sugars? 61 What are complex carbohydrates? 63 Are artificial sweeteners carbohydrates? Are they beneficial or harmful? 65
What functions do carbohydrates serve in the body? 66 How can carbohydrates affect overall health? 67
What role does fiber play in health? 67 What role do simple sugars have in health? 68
How much carbohydrate should be consumed daily? 68 What is the relationship between current body weight and carbohydrate intake? 69 How can carbohydrate needs be determined based
on a percentage of total calories? 69 What impact does the stage of training or competition
schedule have on carbohydrate intake? 70 What are the various sources of dietary carbohydrates? 70
What are the best carbohydrate choices within the grains group? 71 What are the best carbohydrate choices within the fruit and
vegetable groups? 71 What are the best carbohydrate choices within the dairy/alternative group? 71 What are the best carbohydrate choices within the protein foods group? 72
Can foods containing simple sugars or artificial sweeteners be used as a source of carbohydrates? 72
What are the glycemic index and glycemic load, and how can they be used in sports nutrition? 72
What is glycemic load? 73 How does the glycemic index relate to exercise? 74
How are carbohydrates utilized during exercise? 74 How much carbohydrate is stored within the body? 75 Why are carbohydrates an efficient fuel source? 76 Does carbohydrate intake enhance performance? 76 Does carbohydrate intake delay fatigue? 76
What type, how much, and when should carbohydrates be consumed before exercise? 77
What should an athlete eat on the days leading up to an important training session or competition? 78
What should an athlete eat in the hours leading up to an important training session or competition? 78
What type, how much, and when should carbohydrates be consumed during exercise? 81
What types of carbohydrates should be consumed during exercise or sport? 81 How much carbohydrate should be consumed during exercise or sport? 81 When should carbohydrates be consumed during exercise or sport? 83
What type, how much, and when should carbohydrates be consumed after exercise? 83
When should carbohydrates be consumed after exercise or sport? 83 What type of carbohydrates should be consumed after exercise or sport? 84 How much carbohydrate should be consumed after exercise or sport? 85 What are some examples of good meals/snacks for after exercising? 85
Key Points of Chapter 86 Study Questions 87 References 87 Additional Resources 90
CHAPTER 4 Fats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .91 What’s the big deal about fats? 92 What are fats? 92 How are lipids (fats) classified? 92
What are triglycerides? 92 What is the molecular structure of a triglyceride? 92 What are some of the functions of triglycerides in the body? 93 What are fatty acids? 94 What are phospholipids? 98 What are sterols? 99 Is there such a thing as artificial fats? 100
How much fat is recommended in an athlete’s diet? 101 Can a diet be too low in fat? 102 Can a diet be too high in fat? 102
Which foods contain fat? 103 How much fat is in the grains group? 103 How much fat is in the fruit and vegetable groups? 103 How much fat is in the dairy/alternative group? 103 How much fat is in the protein foods group? 104 How much fat is in the oils? 104
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How can the percentage of calories from fat be calculated for specific foods? 104 What’s the big deal about cholesterol? 106
What is dietary cholesterol, and which foods contain it? 106 How is blood cholesterol classified? 106
How can fats affect daily training and competitive performance? 108 What type, how much, and when should fats be consumed before exercise? 110
Is a single high-fat meal prior to exercise beneficial? 110 Is a short-term pattern of eating high-fat meals beneficial
to exercise performance? 110 Is a long-term pattern of eating high-fat meals beneficial
to exercise performance? 110 What are the recommendations for fat intake prior to exercise? 111
What type, how much, and when should fats be consumed during exercise? 111 What type, how much, and when should fats be consumed after exercise? 112 Key Points of Chapter 113 Study Questions 113 References 114 Additional Resources 115
CHAPTER 5 Proteins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116 Why is protein important to athletes? 117 What are proteins? 117
What is the difference between a “complete” and an “incomplete” protein? 119 What are the main functions of proteins in the body? 121 What is nitrogen balance? 123 How much protein should athletes consume daily? 123
How can protein requirements be calculated based on body weight? 123 How do various dietary and training factors affect protein recommendations? 124 Can too much protein be harmful? 126
Which foods contain protein? 127 Which foods in the grains group contain protein? 127 Which foods in the fruit and vegetable groups contain protein? 127 Which foods in the dairy/alternative group contain protein? 128 Which foods make up the protein foods group? 128 Do foods in the oils and empty calories group contain protein? 128
Are protein supplements beneficial? 129 What is the quantity of protein or amino acids in the
product? Is the supplement necessary? 129 What is the cost of protein supplements? 131 Will protein supplements enhance performance? 131 Are there any risks associated with taking the supplement? 132
Why is protein essential for daily training? 132 What type, how much, and when should protein be consumed before exercise? 133
What type and how much protein should be consumed 4 to 24 hours prior to training or competition? 134
What type and how much protein should be consumed 1 to 4 hours prior to training or competition? 134
What type, how much, and when should protein be consumed during exercise? 134 What type, how much, and when should protein be consumed after exercise? 135
Which type of protein or amino acid source is most beneficial to consume after exercise? 135
Is there a recovery benefit of combining carbohydrates and proteins after exercise? 136
Contents vii
How much protein should be consumed after exercise? 136 When should protein or amino acids be consumed after exercise? 137
Key Points of Chapter 138 Study Questions 138 References 139 Additional Resources 140
CHAPTER 6 Vitamins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141 What’s the big deal about vitamins? 142 What are vitamins? 142 How are the dietary needs for vitamins represented? 142 What are the water-soluble vitamins? 142
Why is thiamin important to athletes? 144 Why is riboflavin important for athletes? 144 Why is niacin important for athletes? 145 Why is vitamin B6 important for athletes? 147 Why is vitamin B12 important for athletes? 149 Why is folate important for athletes? 151 Why is biotin important for athletes? 152 Why is pantothenic acid important for athletes? 154 Why is choline important for athletes? 154 Why is vitamin C important for athletes? 156
What are the fat-soluble vitamins? 157 Why is vitamin A important for athletes? 158 Why are the carotenoids important for athletes? 160 Why is vitamin D important for athletes? 161 Why is vitamin E important for athletes? 164 Why is vitamin K important for athletes? 166
Which vitamins or compounds have antioxidant properties? 166 What are free radicals? 166 What is the relationship between free radicals and exercise? 168 Do athletes need antioxidant supplements? 168
What are phytochemicals? 170 What are phenolic compounds? 170 What are organosulfides? 171 What is lycopene? 171 How can athletes increase phytochemical consumption through whole foods? 172
Key Points of Chapter 174 Study Questions 175 References 175 Additional Resource 177
CHAPTER 7 Minerals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178 What’s the big deal about minerals? 179 What are minerals? 179 What are the major minerals? 179
Why is calcium important for athletes? 181 Why is phosphorus important to athletes? 183 Why is magnesium important for athletes? 184 Why is sodium important for athletes? 187 Why is chloride important for athletes? 188 Why is potassium important for athletes? 188 Why is sulfur important for athletes? 190
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What are the trace minerals? 191 Why is iron important for athletes? 191 Why is zinc important for athletes? 195 Why is chromium important for athletes? 196 Why is fluoride important for athletes? 197 Why is copper important for athletes? 199 Why is manganese important for athletes? 200 Why is iodine important for athletes? 201 Why is molybdenum important for athletes? 201 Why is selenium important for athletes? 202 Are other trace minerals important for athletes? 203
Key Points of Chapter 206 Study Questions 206 References 207 Additional Resources 209
CHAPTER 8 Water . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 210 What’s the big deal about water? 211
What are the functions of water in the body? 211 What are the sources of water? 212 What are the ways in which we lose body water? 213
What are the consequences of poor water balance? 214 Is it possible to overhydrate the body? 216 How can hydration status be monitored? 216
How much fluid do individuals need on a daily basis? 218 What are the current recommendations for daily fluid intake? 218 Can certain beverages, foods, or medications contribute to fluid losses? 219 What are some practical guidelines for consuming fluids on a daily basis? 220
What is the role of preexercise hydration? 220 How much fluid should be consumed before exercise? 220 What types of fluids should be consumed? 220 What are practical guidelines for consuming fluids before exercise? 222
What is the role of hydration during exercise? 222 What is the magnitude of water and electrolyte losses during exercise? 222 How much fluid should be consumed during exercise? 223 What types of fluids should be consumed during exercise? 225 What are some practical guidelines for consuming fluids during exercise? 230
What is the role of postexercise hydration? 233 How much fluid should be consumed? 233 What types of fluids should be consumed? 233 Are supplements beneficial after exercise? 234 What are some practical guidelines for consuming
fluids after exercise? 235 Key Points of Chapter 236 Study Questions 236 References 237
CHAPTER 9 Nutritional Ergogenics . . . . . . . . . . . . . . . . . . . . . . . . . . . . 239 What is an ergogenic aid? 240 What are dietary supplements? 241
Why do athletes use dietary supplements? 241 What are the regulations governing dietary supplements? 242 Are some supplements better or safer than others? 244
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Where can information on nutritional ergogenic aids be found? 246 What tools are available to research information on ergogenic aids? 246 What is doping? 248 What are some of the commonly encountered doping substances? 251
Which nutritional ergogenic aids are commonly used as anabolic agents, prohormones, and hormone releasers? 251
Which nutritional ergogenic aids are commonly used to reduce fat mass? 253 Which nutritional ergogenic aids are commonly used as anticatabolics? 253 Which vitamins and minerals are commonly used as nutritional ergogenic aids? 254
What types of dietary supplements and nutritional ergogenics are commonly used by endurance athletes, strength/power athletes, and team sport athletes? 254
Key Points of Chapter 259 Study Questions 259 References 260
SECTION 2 The Practical Application of Sports Nutrition . . . . . . . . 261 CHAPTER 10 Nutrition Consultation with Athletes . . . . . . . . . . . . . . . 263
Why is nutrition consultation and communication with athletes important? 264 How much do athletes know about sports nutrition? 264 Who provides nutrition assessment and education to athletes? 265 How does the consultation process with athletes begin? 266 What is a diet history? 266
What is a health history questionnaire? 266 Why is an inquiry about supplement use important? 268 What type of food intake information should be obtained from the athlete? 268 How is an exercise/training log used in a nutrition consultation? 271 Which clinical assessments should be conducted in
the initial consultation session? 272 How are food records analyzed? 273
How do you compare dietary intake to nutrition recommendations? 274 What are the steps for the initial consultation with the athlete? 277
How is rapport established with an athlete? 278 How can you determine the reasons for a requested consultation? 278 How is the nutrition assessment conducted? 278 How can an athlete’s readiness for change be assessed? 281 How can appropriate nutrition goals be established? 283 How can appropriate nutrition education be provided to an athlete? 284 How should a consultation be summarized and closed? 285
What are the steps for a follow-up consultation with the athlete? 285 What should walk-in or short sessions with athletes involve? 286 Are there any concerns about the confidentiality of the health, nutrition,
and exercise information provided by the athlete? 287 Key Points of Chapter 289 Study Questions 289 References 290
CHAPTER 11 Weight Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 291 What are the common weight management concerns for athletes? 292 What are the prevalence and significance of overweight and obesity? 292
What are the main health consequences and health risks of overweight and obesity? 293
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What methods are used to determine weight status? 294 What is body mass index? 294 What can measures of body fat distribution tell us? 295
Why is body composition important? 296 What makes up the composition of the body? 296 What are the methods for measuring body composition? 297 How does body composition affect sport performance? 301
What are the components of energy intake and energy expenditure? 302 What influences energy intake? 302 What are the components of energy expenditure? 303
What methods do athletes use to lose weight? 306 How are weight and body composition goals for athletes determined? 306 How are energy needs for weight loss determined? 307 What dietary changes are necessary for athletes to lose weight? 307 How do exercise and physical activity influence weight loss for athletes? 309 How does goal setting help athletes lose weight? 310 What are the summary recommendations for athletes regarding weight loss? 311
What are the weight loss issues for athletes in weight classification sports? 312 What happens when weight loss efforts develop into
disordered eating patterns? 315 What are the different types of eating disorders? 315 What are the main concerns regarding female athletes
and eating disturbances/disorders? 317 What are the main concerns regarding male athletes and
eating disturbances/disorders? 319 What are the best treatment options for eating disorders? 320 How can eating disorders be prevented? 320
How can athletes gain weight healthfully? 322 What kind of resistance training program is best for gaining weight? 322 How can an athlete achieve a positive energy balance? 323 How can an athlete achieve a positive nitrogen balance? 324 Do athletes need dietary supplements to gain weight? 324 What other dietary practices might help an athlete gain weight? 325
Key Points of Chapter 326 Study Questions 327 References 327 Additional Resources 329
CHAPTER 12 Endurance and Ultra-Endurance Athletes . . . . . . . . . . . 330 What is different about endurance athletes? 331 What energy systems are utilized during endurance exercise? 331 Are total energy needs for endurance athletes different from
energy needs of other types of athletes? 331 How are daily energy needs calculated for endurance athletes? 332 How many calories should be consumed during
endurance training or competition? 333 How many calories are required after a training session or competitive event? 334
Are macronutrient needs different for endurance athletes? 334 How important are carbohydrates to endurance athletes? 335
How are daily carbohydrate needs calculated for endurance athletes? 335 How should endurance athletes carbohydrate-load before competition? 336 Should carbohydrates be consumed in the hours or