Effect of protein source on resistive-training-induced changes in body composition and muscle size in older men 1 , 2 , 3

BACKGROUND: Aging is associated with reductions in muscle mass and strength, but nutrition and exercise interventions can delay this progression and enhance the quality of life. OBJECTIVE: We examined whether the predominant source of protein consumed by older men influenced measures of muscle size and strength, body composition, resting energy expenditure, and skeletal muscle creatine concentrations in response to 12 wk of resistive training.