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Effect of altering substrate availability on metabolism and performance during intense exercise

Published online by Cambridge University Press:  09 March 2007

John A. Hawley*
Affiliation:
Exercise Metabolism Group, Department of Human Biology & Movement Science, R.M.I.T. University, Victoria 3083, Australia
Louise M. Burke
Affiliation:
Department of Sports Nutrition, Sports Medicine & Applied Physiology, The Australian Institute of Sport, ACT 2616, Australia
Damien J. Angus
Affiliation:
Exercise Physiology and Metabolism Laboratory, Department of Physiology, The University of Melbourne, Victoria 3052, Australia
Kieran E. Fallon
Affiliation:
Department of Sports Nutrition, Sports Medicine & Applied Physiology, The Australian Institute of Sport, ACT 2616, Australia
David T. Martin
Affiliation:
Department of Sports Nutrition, Sports Medicine & Applied Physiology, The Australian Institute of Sport, ACT 2616, Australia
Mark A. Febbraio
Affiliation:
Exercise Physiology and Metabolism Laboratory, Department of Physiology, The University of Melbourne, Victoria 3052, Australia
*
*Corresponding author: Dr John A. Hawley, fax +61 3 9467 8181, email John.hawley@rmit.edu.au
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Abstract

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The purpose of this study was to determine the effect of altering substrate availability on metabolism and performance during intense cycling. Seven highly trained men ingested a random order of three isoenergetic meals 90 min before cycling at 80 % maximal oxygen uptake (VO2max) for 20 min (about 310 W), followed by a 600 kJ time trial lasting about 30 min. Meals consisted of either 1·2 g saturated fat/kg body mass (BM) with 3500 U heparin intravenously (HIFAT) to elevate circulating plasma free fatty acid (FA) concentration, 2·5 g carbohydrate/kg BM (CHO) to elevate plasma glucose and insulin concentrations or 2·5 g carbohydrate+20 mg nicotinic acid/kg BM (NA) to suppress lipolysis and reduce free FA concentration. HIFAT elevated free FA concentration (HIFAT 1·3 (SEM 0·2), CHO 0·2 (sem 0·1), NA 0·1 (sem 0·1) mm; P<0·001), lowered the RER (HIFAT 0·94 (sem 0·01), CHO 0·97 (sem 0·01), NA 0·98 (sem 0·01); P<0·01) and increased the rate of fat oxidation (HIFAT 24 (sem 3), CHO 12 (sem 2), NA 8 (sem 3) μmol/kg per min; P<0·01) during the 20 min ride. Marked differences in fat availability and fuel utilisation, however, had little effect on performance in the subsequent time trial (HIFAT 320 (sem 16), CHO 324 (sem 15), NA 315 (sem 13) W). We conclude: (1) increased fat availability during intense cycling increases the rate of fat oxidation; but (2) the reduction in the rate of carbohydrate oxidation in the presence of high circulating plasma free FA is unlikely to enhance intense exercise performance lasting about 1 h; (3) substrate selection during intense (about 80 % VO2max) exercise is dominated by carbohydrate oxidation.

Type
Research Article
Copyright
Copyright © The Nutrition Society 2000

References

Bergman, BC & Brooks, GA (1999) Respiratory gas-exchange ratios during graded exercise in fed and fasted trained and untrained men. Journal of Applied Physiology 86, 479487.CrossRefGoogle ScholarPubMed
Bergstrom, J, Hultman, E, Jorfeldt, L, Pernow, B & Wahren, J (1969) Effect of nicotinic acid on physical working capacity and on metabolism of muscle glycogen in man. Journal of Applied Physiology 26, 170176.CrossRefGoogle ScholarPubMed
Borg, G (1975) Simple rating method for estimation of perceived exertion. In Physical Work and Effort, pp. 3946. [Borg, G, editors]. New York: Pergamon.Google Scholar
Brooks, GA & Mercier, J (1994) Balance of carbohydrate and lipid utilization during exercise: the "crossover" concept. Journal of Applied Physiology 76, 22532261.CrossRefGoogle ScholarPubMed
Camps, L, Reina, M & Lobera, M (1990) Lipoprotein lipase: cellular origin and functional distribution. American Journal of Physiology 258, C673C681.CrossRefGoogle ScholarPubMed
Carlson, LA, Havel, RJ, Ekelund, LG & Holmgren, A (1963) Effect of nicotinic acid on the turnover rate and oxidation of the free fatty acids of plasma in man during exercise. Metabolism Clinical Experiment 12, 837845.Google ScholarPubMed
Costill, DL, Coyle, E, Dalsky, G, Evans, W, Fink, W & Hoopes, D (1977) Effects of elevated plasma FFA and insulin on muscle glycogen usage during exercise. Journal of Applied Physiology 43, 695699.CrossRefGoogle ScholarPubMed
Coyle, EF, (1997) Fuels for sport performance. In Perspectives in Exercise Science and Sports Medicine. Volume 10. Optimising Sport Performance 105129. [Lamb, DR and Murray, R, editors]. Carmel, IN: Cooper Publishing Group.Google Scholar
Coyle, EF, Jeukendrup, AE, Wagenmakers, AJM & Saris, WHM (1997) Fatty acid oxidation is directly regulated by carbohydrate metabolism during exercise. American Journal of Physiology 273, E268E275.Google ScholarPubMed
Dipalma, JR & Thayer, WS (1991) Use of niacin as a drug. Annual Review of Nutrition 11, 169187.CrossRefGoogle ScholarPubMed
Dyck, DJ, Peters, SJ, Wendling, PS, Chesley, A, Hultman, E & Spriet, LL (1996) Regulation of muscle glycogen phosphorylase activity during intense aerobic cycling with elevated FFA. American Journal of Physiology 270, E116E125.Google ScholarPubMed
Dyck, DJ, Putman, CT, Heigenhauser, GJF, Hultman, E & Spriet, LL (1993) Regulation of fat–carbohydrate interaction in skeletal muscle during intense aerobic cycling. American Journal of Physiology 265, E852E859.Google ScholarPubMed
Flynn, MG, Costill, DL, Hawley, JA, Fink, WJ, Neufer, PD, Fielding, RA & Sleeper, MD (1987) Influence of selected carbohydrate drinks on cycling performance and glycogen use. Medicine & Science in Sports & Exercise 19, 3740.CrossRefGoogle ScholarPubMed
Gore, CJ, Catcheside, PG, French, SN, Bennett, JM & Laforgia, DJ (1997) Automated VO2max calibrator for open circuit indirect calorimetry systems. Medicine & Science in Sports & Exercise 29, 10951103.CrossRefGoogle ScholarPubMed
Hawley, JA, (2000) Nutritional strategies to enhance fat oxidation during aerobic exercise. In Clinical Sports Nutrition 428454. [Burke, LM and Deakin, V, editors]. Sydney: McGraw-Hill.Google Scholar
Hawley, JA, Brouns, F & Jeukendrup, AE (1998) Strategies to enhance fat utilisation during exercise. Sports Medicine 25, 241257.CrossRefGoogle ScholarPubMed
Hawley, JA & Noakes, TD (1992) Peak sustained power output predicts VO2max and performance time in trained cyclists. European Journal of Applied Physiology 65, 7983.CrossRefGoogle Scholar
Hawley, JA, Palmer, GS & Noakes, TD (1997) Effects of 3 days of carbohydrate supplementation on muscle glycogen content and utilisation during a 1-h cycling performance. European Journal of Applied Physiology 75, 407412.CrossRefGoogle ScholarPubMed
Hodgetts, V, Coppack, SW, Frayn, KN & Hockaday, TDR (1991) Factors controlling fat mobilization from human subcutaneous adipose tissue during exercise. Journal of Applied Physiology 71, 445451.CrossRefGoogle ScholarPubMed
Hopkins, WG, Burke, LM & Hawley, JA (1999) Design and analysis of research on sport performance enhancement. Medicine & Science in Sports & Exercise 31, 472485.CrossRefGoogle ScholarPubMed
Horowitz, JF, Mora-Rodriguez, R, Byerley, LO & Coyle, EF (1997) Lipolytic suppression following carbohydrate ingestion limits fat oxidation during exercise. American Journal of Physiology 273, E768E775.Google ScholarPubMed
Kjaer, MB, Kiens, B, Hargreaves, M & Richter, EA (1991) Influence of active muscle mass on glucose homeostasis during exercise in humans. Journal of Applied Physiology 71, 552557.CrossRefGoogle ScholarPubMed
Marcus, C, Sonnenfeld, T, Karpe, B, Bolme, P & Arner, P (1989) Inhibition of lipolysis by agents acting via adenylate cyclase in fat cells from infants and adults. Pediatric Research 26, 255259.CrossRefGoogle Scholar
Murray, R, Bartolli, WP, Eddy, DE & Horn, MK (1995) Physiological and performance responses to nicotinic-acid ingestion during exercise. Medicine & Science in Sports & Exercise 27, 10571062.CrossRefGoogle ScholarPubMed
Neufer, PD, Costill, DL, Flynn, MG, Kirwan, JP, Mitchell, JB & Houmard, J (1987) Improvements in exercise performance: effects of carbohydrate feedings and diet. Journal of Applied Physiology 62, 983988.CrossRefGoogle ScholarPubMed
Odland, LM, Heigenhauser, GJ, Hollidge-horvat, MG & Spriet, LL (1998) Effects of increased fat availability on fat-carbohydrate interaction during prolonged exercise in men. American Journal of Physiology 274, R894R902.Google ScholarPubMed
Okano, G, Sato, Y & Murata, Y (1998) Effect of elevated blood FFA levels on endurance performance after a single fat meal ingestion. Medicine & Science in Sports & Exercise 30, 763768.CrossRefGoogle ScholarPubMed
Okano, G, Sato, Y, Takumi, M & Sugawara, M (1996) Effect of 4-h pre-exercise high carbohydrate and high fat meal ingestion on endurance performance and metabolism. International Journal of Sports Medicine 17, 530534.CrossRefGoogle Scholar
Pernow, B, Havel, RJ & Jennings, DB (1967) The second wind phenomenon in McArdles syndrome. Acta Medica Scandinavia Suppl. 472, 294307.CrossRefGoogle Scholar
Pernow, B & Saltin, B (1971) Availability of substrates and capacity for prolonged heavy exercise in man. Journal of Applied Physiology 31, 416422.CrossRefGoogle ScholarPubMed
Peronnet, F & Massicotte, D (1991) Table of nonprotein respiratory quotient: an update. Canadian Journal of Sports Science 16, 2329.Google ScholarPubMed
Pinter, JK, Hayashi, JA & Watson, JA (1967) Enzymatic assay of glycerol, dihydroxyacetone and glyceraldehyde. Archives of Biochemistry Biophysics 121, 404.CrossRefGoogle Scholar
Pitsiladis, YP, Smith, I & Maughan, RJ (1999) Increased fat availability enhances the capacity of trained individuals to perform prolonged exercise. Medicine & Science in Sports & Exercise 31, 15701579.CrossRefGoogle ScholarPubMed
Randle, P, Garland, P, Hales, C & Newsholme, E (1963) The glucose fatty acid cycle. Its role in insulin sensitivity and the metabolic disturbances of diabetes mellitus. Lancet 1, 785789.CrossRefGoogle ScholarPubMed
Robergs, RA; Roberts, SO; 2000 Fundamental Principles of Exercise Physiology, pp. 67. Boston, MA: McGraw Hill.Google Scholar
Romijn, JA, Coyle, EF, Hibbert, J & Wolfe, RR (1992) Comparison of indirect calorimetry and a new breath 13C/12C ratio method during strenuous exercise. American Journal of Physiology 263, E64E71.Google Scholar
Romijn, JA, Coyle, EF, Sidossis, LS, Gastaldelli, A, Horowitz, JF, Endert, E & Wolfe, RR (1993) Regulation of endogenous fat and carbohydrate metabolism in relation to exercise intensity and duration. American Journal of Physiology 265, E380E391.Google ScholarPubMed
Romijn, JA, Coyle, EF, Sidossis, LS, Zhang, XJ & Wolfe, RR (1995) Relationship between fatty acid delivery and fatty acid oxidation during strenuous exercise. Journal of Applied Physiology 79, 19391945.CrossRefGoogle ScholarPubMed
Sidossis, LS, Gastaldelli, A, Klein, S & Wolfe, RR (1997) Regulation of plasma fatty acid oxidation during low- and high-intensity exercise. American Journal of Physiology 272, E1065E1070.Google ScholarPubMed
Spriet, LL, Maclean, DA, Dyck, DJ, Hultman, E, Cederblad, G & Graham, TE (1992) Caffeine ingestion and muscle metabolism during prolonged exercise in humans. American Journal of Physiology 262, E891E898.Google ScholarPubMed
Vukovich, MD, Costill, DL, Hickey, MS, Trappe, SW, Cole, KJ & Fink, WJ (1993) Effect of fat emulsion, infusion and fat feeding on muscle glycogen utilization during cycle exercise. Journal of Applied Physiology 75, 15131518.CrossRefGoogle ScholarPubMed
Whitley, HA, Humphreys, SM, Campbell, IT, Keegan, MA, Jayanetti, TD, Sperry, DA, Maclaren, DP, Reilly, T & Frayn, KN (1998) Metabolic and performance responses during endurance exercise after high-fat and high-carbohydrate meals. Journal of Applied Physiology 85, 418424.CrossRefGoogle ScholarPubMed