Energy metabolism of medium-chain triglycerides versus carbohydrates during exercise

  • J. Décombaz
  • M. -J. Arnaud
  • H. Milon
  • H. Moesch
  • G. Philippossian
  • A. -L. Thélin
  • H. Howald


Medium-chain triglycerides (MCT) are known to be rapidly digested and oxidized. Their potential value as a source of dietary energy during exercise was compared with that of maltodextrins (MD). Twelve subjects exercised for 1 h on a bicycle ergometer (60% \(\dot V\)O2 max), 1 h after the test meal (1MJ). The metabolism of MCT was followed using 1-13C-octanoate (Oc) as tracer and U-13C-glucose (G) was added to the 13C-naturally enriched MD.

After MCT ingestion no insulin peak was observed with some accumulation of ketone bodies (KB), blood levels not exceeding 1 mM. Total losses of KB during exercise in urine, sweat and as breath acetone were small (<0.2 mmol·h−1). Hence, the influence of KB loss and storage on gas exchange data was negligible.

The partition of fat and carbohydrate utilization during exercise as obtained by indirect calorimetry was practically the same after the MCT and the CHO meals. Oxidation over the 2-h period was 30% of dose for Oc and 45% for G. Glycogen decrements in the Vastus lateralis muscle were equal. It appears that with normal carbohydrate stores, a single meal of MCT or CHO did not alter the contribution of carbohydrates during 1 h of high submaximal exercise. The moderate ketonemia after MCT, despite substantial oxidation of this fat, led to no difference in muscle glycogen sparing between the diets.

Key words

Muscle glycogen 1-13C-octanoate U-13C-glucose Ketones Respiratory exchange ratio 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. åstrand PO, Rodahl K (1970) Textbook of work physiology. MacGraw-Hill, New York, p 617Google Scholar
  2. Bach A, Debry G, Metais P (1977) Hepatic metabolism of medium chain triglycerides. Bibl Nutr Diet 25: 24–35Google Scholar
  3. Baker N, Shreeve WW, Shipley RA, Incefy GE, Miller H (1954) C14 studies in carbohydrate m etabolism. 1. The oxidation of glucose in normal human subjects. J Biol Chem 211: 575–592PubMedGoogle Scholar
  4. Balasse EO, Fery F, Neef MA (1978) Changes induced by exercise in rates of turnover and oxidation of ketone bodies in fasting man. J Appl Physiol 44: 5–11PubMedGoogle Scholar
  5. Berger M, Kemmer FW, Goodman MN, Zimmermann-Telschow H, Ruderman NB (1978) Ketone body metabolism in isolated perfused muscle in various metabolic states. In: Soling HD, Senfert D (eds) Biochemical and clinical aspects of ketone body metabolism. Georg Thieme, Stuttgart, pp 192–203Google Scholar
  6. Bergström J (1962) Muscle electrolytes in man. Determined by neutron activation analysis on needle biopsy specimens. A study on normal subjects, kidney patients, and patients with chronic diarrhoea. Scand J Clin Lab Invest [Suppl 68] 14: 1–110Google Scholar
  7. Bergström J, Hermansen L, Hultman E, Saltin B (1967) Diet, muscle glycogen and physical performance. Acta Physiol Scand 71: 140–150PubMedGoogle Scholar
  8. Bogardus C, LaGrange BM, Horton ES, Sims EA (1981) Comparison of carbohydrate-containing and carbohydrate-restricted hypocaloric diets in the treatment of obesity: endurance and metabolic fuel homeostasis during strenuous exercise. J Clin Invest 68: 399–404PubMedGoogle Scholar
  9. Christensen EH, Hansen O (1939) HypoglykÄmie, ArbeitsfÄhigkeit und Ermüdung. Skand Arch Physiol 81: 172–179Google Scholar
  10. Consolazio CF, Johnson RE, Pecora LH (1963) Physiological measurements of metabolic functions in man. McGraw-Hill, New-York, p 316Google Scholar
  11. 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. J Appl Physiol 43: 695–699PubMedGoogle Scholar
  12. Décombaz J, Roux L (1980) Glycogen utilization in exercise after increased plasma fatty acids or ketone bodies (Research note) Int J Vit Nutr Res 50: 210–211Google Scholar
  13. Freund G, Weinsier RL (1966) Standardized ketosis in man following medium chain triglyceride ingestion. Metabolism 15: 980–991PubMedCrossRefGoogle Scholar
  14. Hagenfeldt L (1979) Metabolism of free fatty acids and ketone bodies during exercise in normal and diabetic man. Diabetes [Suppl 1] 28: 66–70PubMedGoogle Scholar
  15. Hales CN, Randle PJ (1963) Immunoassay of insulin with insulin-antibody precipitate. Biochem J 88: 137–148PubMedGoogle Scholar
  16. Hermansen L, Hultman E, Saltin B (1967) Muscle glycogen during prolonged severe exercise. Acta Physiol Scand 71: 129–139PubMedGoogle Scholar
  17. Hickson RC, Rennie MJ, Conlee RK, Winder WW, Holloszy JO (1977) Effects of increased plasma fatty acids on glycogen utilization and endurance. J Appl Physiol 43: 829–833PubMedGoogle Scholar
  18. Issekutz B, Miller HI, Rodahl K (1966) Lipid and carbohydrate metabolism during exercise. Fed Proc 25: 1415–1420PubMedGoogle Scholar
  19. Ivy JL, Costill DL, Fink WJ, Maglischo E (1980) Contribution of medium and long chain triglycerides intake to energy metabolism during prolonged exercise. Int J Sports Med 1: 15–20CrossRefGoogle Scholar
  20. Keppler D, Decker K (1970) Glykogen. Bestimmung mit Amyloglucosidase. In: Bergmeyer HU (ed) Methoden der enzymatischen Analyse, vol. II, 2nd ed. Verlag Chemie, Weinheim, pp 1089–1094Google Scholar
  21. Keys A, BroŽek J, Henschel A, Mickelson O, Taylor HL (1950) The biology of human starvation. University of Minnesota Press, Minneapolis, pp 74, 512, 717Google Scholar
  22. Lusk G (1928) The elements of the science of Nutrition (4th ed). W. B. Saunders, Philadelphia, p 65Google Scholar
  23. Minuk HL, Hanna AK, Marliss EB, Vranic M, Zinman B (1980) Metabolic response to moderate exercise in obese man during prolonged fasting. Am J Physiol 238: E322-E329PubMedGoogle Scholar
  24. Owen OE, Reichard GA, Jr (1971) Human forearm metabolism during progressive starvation. J Clin Invest 50: 1536–1545PubMedCrossRefGoogle Scholar
  25. Passonneau JV, Lauderdale VR (1974) A comparison of three methods of glycogen measurement in tissues. Anal Biochem 60: 405–412PubMedCrossRefGoogle Scholar
  26. Phinney SD, Horton ES, Sims EAH, Hanson JS, Danforth E, LaGrange BM (1980) Capacity for moderate exercise in obese subjects after adaptation to a hypocaloric diet. J Clin Invest 66: 1152–1161PubMedGoogle Scholar
  27. Phinney SD, Bistrian BR, Evans WJ, Wolfe RW, Blackburn GL (1981) Reduced carbohydrate oxidation during submaximal exercise by trained cyclists after adaptation to an eskimo diet. [Abstract] Med Sci Sports 13: 111Google Scholar
  28. Randle PJ, Newsholme EA, Garland PB (1964) Regulation of glucose uptake by muscle. 8. Effects of fatty acids, ketone bodies and pyruvate, and of alloxan-diabetes and starvation, on the uptake and metabolic fate of glucose in rat heart and diaphragm muscles. Biochem J 93: 652–665PubMedGoogle Scholar
  29. Rayussin E, Pahud P, Dörner A, Arnaud MJ, Jéquier E (1979) Substrate utilization during prolonged exercise preceded by ingestion of 13C-glucose in glycogen depleted and control subjects. Pflügers Arch 382: 197–202CrossRefGoogle Scholar
  30. Reichard GA Jr, Haff AC, Skutches CL, Paul P, Holryde CP, Owen OE (1979) Plasma acetone metabolism in the fasting human. J Clin Invest 63: 619–626PubMedGoogle Scholar
  31. Rennie MJ, Winder WW, Holloszy JO (1976) A sparing effect of increased plasma fatty acids on muscle and liver glycogen content in the exercising rat. Biochem J 156: 647–655PubMedGoogle Scholar
  32. Rennie MJ, Holloszy JO (1977) Inhibition of glucose uptake and glycogenolysis by availability of oleate in well-oxygenated perfused skeletal muscle. Biochem J 168: 161–170PubMedGoogle Scholar
  33. Sanbar SS, Hetenyi G, Jr, Forbath N, Evans JR (1965) Effect of infusion of octanoate on glucose concentration in plasma and the rates of glucose production and utilization in dogs. Metabolism 14: 1311–1323PubMedGoogle Scholar
  34. Sapir DG, Owen OE (1975) Renal conservation of ketone bodies during starvation. Metabolism 24: 23–33PubMedCrossRefGoogle Scholar
  35. Sonnenberg GE, Keller U (1979) Application of ketone body tracer infusions to determine ketone body turnover during non-steady state in man [Abstract]. In: 10th Congress of the International Diabetes Federation, Vienna, September 1979, vol. 481. Excerpta Medica, p 221Google Scholar
  36. Wick AN, Drury DR (1941) The effect of concentration on the rate of utilization of Β-hydroxybutyric acid by the rabbit. J Biol Chem 138: 129–133Google Scholar
  37. Ye YY, Zee P (1976) Relation of ketosis to metabolic changes induced by acute medium-chain triglycerides feedings in rats. J Nutr 106: 58–67Google Scholar

Copyright information

© Springer-Verlag 1983

Authors and Affiliations

  • J. Décombaz
    • 2
  • M. -J. Arnaud
    • 2
  • H. Milon
    • 2
  • H. Moesch
    • 2
  • G. Philippossian
    • 2
  • A. -L. Thélin
    • 2
  • H. Howald
    • 1
  1. 1.Research Institute of the Swiss School for Physical Education and SportsMagglingen/MacolinSwitzerland
  2. 2.Nestlé Research DepartmentLa Tour-de-PeilzSwitzerland

Personalised recommendations