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

Abstract

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 x kg(-1) x h(-1) (study A) or 0.8 g CHO x kg(-1) x 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< or = 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.