Number of sets for muscular hypertrophy:
Krieger studied the effects of single to multiple sets per exercise on muscle hypertrophy (enlargement in muscle size) Results of the study found that multiple sets per exercise were associated with significantly greater modifications in muscle size during resistance programs. Specifically, multiple sets had 40% greater hypertrophy-related effect sizes than a single set. Also, there was a trend toward dose effects (i.e., increasing muscle size with increasing number of sets). Findings from this study suggest that performing a minimum of 2-3 sets per exercise and possibly, 4-6 sets would be more effective in achieving maximal hypertrophy in both trained and untrained subjects. (5)