Carbohydrates Study: Are Carbs Anticatabolic?

A soon-to-be-published study, which is slated for the Journal of Applied Physiology, shows that properly timed carbohydrate intake may be a potent stimulus for muscle gains. The study involved eight healthy men who did leg extensions for eight sets of 10 repetitions using weights that were 85% of 1RM (one-rep maximum). The men received either a carbohydrate supplement (one gram per kilogram of bodyweight) or a placebo immediately after the workout and one hour later. The extent of muscle-protein synthesis in the men was determined by specially labeled isotopes of the amino acid leucine, which is incorporated into muscle during protein synthesis.

The results showed that insulin levels climbed incrementally following the workout and that blood-glucose levels peaked at 30 and 45 minutes after ingestion of the carb supplement. Significantly, muscle-protein synthesis increased 36% more in the carb group than in those receiving the placebo. Those taking the carbs also showed decreased rates of 3-methyl histidine (a sign of muscle-protein breakdown) and urinary urea excretion (another index of muscle catabolism). This study clearly proves that consuming a certain level of carbohydrates - in this case, one gram per 2.2 pounds of bodyweight - after intensive training mitigates muscle-protein breakdown.

This, in turn, leads to a more positive nitrogen balance and consequent upgraded anabolic effects in muscle,