Sucres, métabolisme musculaire et exercice physique

Muscles mainly draw their energy from lipids and carbohydrates. During physical exercice, glucose consumption by muscle considerably increases. Glucose, oxidized during physical activity, comes from glycogen stores from liver and muscles, and/or from ingested carbohydrates. Performance could be enhanced by the increase of intracellular glycogen stores and by carbohydrate ingestion before and during exercice. Several mechanisms may be involved: maintaining blood glucose and high levels of CHO oxidation, sparing endogenous glycogen, delaying time to exhaustion. However, short-term exercices (< 1 hour) do not require changes in food intake. Beyond, it seems important to make sufficient glycogen stores before exercise, using suitable diets. Glycogen stores replenishment after exercise should be done as soon as possible after the end of exercise. Based on this knowledge, nutrition recommendations can be made to sportmen and women, according to the type of exercise and of studied subjects.