Advances in Nutrition and Top Sport

Advances in Nutrition and Top Sport

Medicine and Sport Science Vol. 32 Series Editors M. Hebbelinck, Brussels R.J. Shephard, Toronto Founder and Editor from 1969 to 1984 E. Jokl, Lexington, Ky. KARG E R. Basel München Paris. London NewYork New Delhi Bangkok. Singapore.Tokyo Sydney

Advances in Nutrition and Top Sport Volume Editor F. Brouns, Maastricht Associate Editors W.KM Saris, Maastricht E.A. Newsholme, Oxford 36 figures and 18 tables, 1991 KARGER Basel München Paris London NewYork New Delhi Bangkok Singapore Tokyo Sydney

Medicine and Sport Science Published on behalf of the International Council of Sport Science and Physical Education Library of Congress Cataloging-in-Publication Data Advances in nutrition and top sport / volume editor, F. Brouns; associate editors, W.H.M. Saris, E.A. Newsholme. (Medicine and sport science; vol. 32) `Published on behalf of the Research Committee of the International Council of Sport Science and Physical Education' Iπcludes bibliographical references and index. 1. Sports -- Physiological aspects. 2. Athletes -- Nutrition. I. Brouns, F. (Fred) II. Saris, Wilhelmus Hermanus Marla, 1949. III. Newsholme, E.Α. IV. International Council of Sport Science and Physical Education. Research Committee. V. Series. [DNLM: 1. Exercise. 2. Nutrition. 3. Sports.] ISBN 3-8055-5376-5 (alk. paper) Drug Dosage The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any change in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug. All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher. Copyright 1991 by S. Karger AG, P.O. Box, CH 4009 Basel (Switzerland) Printed in Switzerland on acid-free paper by Thür AG Offsetdruck, Pratteln ISBN 3-8055-5376-5

Contents Preface VII Coyle, E.F. (Austin, Tex.): Carbohydrate Feedings: Effects on Metabolism, Perfor mance and Recovery 1 Lemon, P.W.R. (Kent, Ohio): Does Exercise Alter Dietary Protein Requirements? 15 Anderson, R.A. (Beltsville, Md.): New Insights on the Trace Elements, Chromium, Copper and Zinc, and Exercise 38 Bendich, A. (Nutley, N.J.): Exercise and Free Radicals: Effects of Antioxidant Vitamins 59 Newsholme, Ε.A.; Parry-Billings, M.; McAndrew, N. (Oxford); Budgett, R. (Harrow): A Biochemical Mechanism to Explain Some Characteristics of Overtraining 79 Wurtman, R.J.; Lewis, M.C. (Cambridge, Mass.): Exercise, Plasma Composition, and Neurotransmission 94 Wagenmakers, A.J.M. (Maastricht): L-Carnítíne Supplementation and Performance in Man 110 Rehrer, N.J. (Brussels): Aspects of Dehydration and Rehydration during Exercise 128 Maughan, R.J. (Aberdeen); Greenhaff, P.L. (Birmingham): High Intensity Exercise Performance and Acid-Base Balance: The Influence of Diet and Induced Metabolic Alkalosis 147 Brouns, F. (Maastricht): Gastrointestinal Symptoms in Athletes: Physiological and Nutritional Aspects 166 Saris, W.H.M. (Maastricht): Exercise, Nutrition and Weight Control 200 Subject Index 217

Preface During the last decade the role of nutrition as an important factor in the preparation and performance of athletes has received renewed attention. A large number of studies have been performed in order to elucidate in particular the effect of exercise on metabolism and the effect of specific dietary measures on substrate supply and hormonal regulation. The development of a `fitness image' has led many people to start with some kind of endurance exercise and it was especially this development which has `awakened' the sports-related industry. As a result, on the one hand, the scientific community has been supported by the food industry to perform studies in the field of nutrition and exercise, a collaboration which has been shown to be of utmost importance for scientific progress in this field. On the other hand, a large number of food products have overwhelmed the sports world, many of which are claimed to improve performance and health, without any scientific evidence. In the volume presented here, the reader will find a number of chapters which stem from the special symposium `Nutrition and Top Sport' which took place during the FIMS World Conference on Sports Medicine, May 1990, Amsterdam, The Netherlands. The goal of this symposium was to provide an update of classical sports nutritional topics, such as carbohydrate, protein, fluids and electrolytes and to introduce developing fields of scientific interest which particularly focus on health and well-being of athletes, such as gastrointestinal function, immune status and free radical pathology. In addition to these chapters, several authors have been invited to present a chapter on a specific sports nutritional topic, which has recently undergone new developments and/or has led to controversial interpretations and opinions.

Preface VIII As such, the chapters on trace elements, dietary influences on acid base balance, slimming and exercise and L-carnítíne complete this book to a hopefully valuable source of information on the advancement of sports nutritional research. The symposium `Nutrition and Top Sport' as well as the preparation of this volume were supported by an `Isostar Science Grant' from Sandoz Nutrition, Bern, Switzerland. Dr. Fred Brouns Prof. Wim Η.M. Saris Prof. Eric A. Newsholme