Does whey-protein and leucine enhance physical performance, cognitive performance and lean body mass?

From: International Journal of Sports Nutrition and Exercise Metabolism

Journal rating:
rating: 54%
Study Quality:
rating: 85%

Overall Reliability

Article Quality:
rating: 5%
rating: 0%


  • 30 moderately fit participants


  • Participants supplemented their daily diet for 8 wk with either 19.7 g of whey protein and 6.2g leucine (WPL) or a calorie-equivalent placebo (P).


  • Bench-press performance increased significantly from Week 1 to Week 8 in the WPL group, whereas the increase in the P group was not significant.
  • Push-up performance increased significantly for WPL, and P showed a nonsignificant increase.
  • Total mass, fat-free mass, and lean body mass all increased significantly in the WPL group but showed no change in the P group.
  • No differences were observed within or between groups for crunches, chin-ups, 3-mile-run time, or cognition


  • Yes (without confidence)


Editors Notes

  • The authors conclude that supplementing with whey protein and leucine may provide an advantage to people whose performance benefits from increased upper body strength and/or lean body mass.