Significant effect of a pre-exercise high-fat meal after a 3-day high-carbohydrate diet on endurance performance

Nutrients. 2012 Jul;4(7):625-637. doi: 10.3390/nu4070625. Epub 2012 Jun 27.


We investigated the effect of macronutrient composition of pre-exercise meals on endurance performance. Subjects consumed a high-carbohydrate diet at each meal for 3 days, followed by a high-fat meal (HFM; 1007 ± 21 kcal, 30% CHO, 55% F and 15% P) or high-carbohydrate meal (HCM; 1007 ± 21 kcal, 71% CHO, 20% F and 9% P) 4 h before exercise. Furthermore, just prior to the test, subjects in the HFM group ingested either maltodextrin jelly (M) or a placebo jelly (P), while subjects in the HCM ingested a placebo jelly. Endurance performance was measured as running time until exhaustion at a speed between lactate threshold and the onset of blood lactate accumulation. All subjects participated in each trial, randomly assigned at weekly intervals. We observed that the time until exhaustion was significantly longer in the HFM + M (p < 0.05) than in HFM + P and HCM + P conditions. Furthermore, the total amount of fat oxidation during exercise was significantly higher in HFM + M and HFM + P than in HCM + P (p < 0.05). These results suggest that ingestion of a HFM prior to exercise is more favorable for endurance performance than HCM. In addition, HFM and maltodextrin ingestion following 3 days of carbohydrate loading enhances endurance running performance.

Keywords: carbohydrate oxidation; fat oxidation; glycogen; marathon; metabolism.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Blood Glucose / analysis
  • Cross-Over Studies
  • Diet*
  • Dietary Carbohydrates / administration & dosage*
  • Dietary Fats / administration & dosage*
  • Double-Blind Method
  • Energy Metabolism / physiology
  • Fatty Acids, Nonesterified / blood
  • Glycogen / metabolism
  • Humans
  • Insulin / blood
  • Lactates / blood
  • Male
  • Nutritional Status
  • Physical Endurance / physiology*
  • Pulmonary Gas Exchange
  • Running / physiology*
  • Young Adult


  • Blood Glucose
  • Dietary Carbohydrates
  • Dietary Fats
  • Fatty Acids, Nonesterified
  • Insulin
  • Lactates
  • Glycogen