Recovery of endurance running capacity: effect of carbohydrate-protein mixtures

Including protein in a carbohydrate solution may accelerate both the rate of glycogen storage and the restoration of exercise capacity following prolonged activity. Two studies were undertaken with nine active men in study A and seven in study B. All participants performed 2 trials, each involving a 90 min run at 70% VO2max followed by a 4 h recovery. During recovery, either a 9.3% carbohydrate solution (CHO) or the same solution plus 1.5% protein (CHO-PRO) was ingested every 30 min in volumes providing either 1.2 g CHO · kg-1 · h-1 (study A) or 0.8 g CHO · kg-1 · h-1 (study B). Exercise capacity was then assessed by run time to exhaustion at 85% VO2max. Ingestion of CHO-PRO elicited greater insulinemic responses than CHO (P less than or equal to 0.05) but with no differences in run times to exhaustion. Within the context of this experimental design, CHO and CHO-PRO restored running capacity with equal effect.