Whey protein hydrolysate supplementation accelerates recovery from exercise-induced muscle damage in females

A number of different forms of protein and their analogues have been investigated for their efficacy in ameliorating exercise-induced muscle damage (EIMD) and recovery. Preliminary data regarding whey protein hydrolysate (WPH) supplementation are promising. However, its efficacy beyond acute eccentric/resistance exercise bouts or longer-term training programmes are limited and all investigations have been conducted in male or mixed-sex groups. This study sought to elucidate whether the benefits of WPH previously reported can be demonstrated in females following repeated-sprint exercise. Twenty physically active females were assigned to consume two doses of 70 ml WPH or isoenergetic carbohydrate (CHO) for 4 days post EIMD. Measures of muscle soreness, limb girth, flexibility, muscle function and creatine kinase were collected pre, immediately post, and 24, 48 and 72 h post-exercise. Time effects were observed for all variables (p <0.05) except limb girth; indicative of EIMD. Flexibility improved beyond baseline measures following WPH by 72 h, but had failed to recover in the CHO group (p = 0.011). Reactive strength index was higher throughout recovery in the WPH group compared to CHO (p = 0.016). Reductions in creatine kinase were greater following WPH compared to CHO at 48 h post EIMD (p = 0.031). The findings suggest that four day supplementation of WPH is beneficial for reducing symptoms of EIMD and improving recovery of muscle function in physically active females.