This study examined the effects of different volumes of resistance training on muscle size and function over a 10-wk period. Low volume = 3 sets per muscle group per week; moderate = 6 sets; high = 12 sets. Twenty-seven men with 1–4 yrs weight training experience were randomly assigned to the different training volumes and trained 4 days a week. A periodized routine was used; exercises, training intensity, and number of training days were the same for each group. The only variation between conditions was the number of sets per exercise. Pre and post measurements assessed muscular size via ultrasound; strength via maximum squat and bench press; and power via vertical jump and bench press throw. Urinary concentrations of test-osterone and cortisol were also analyzed to assess the responses to training conditions. All 3 training volumes significantly (p < 0.05) increased muscle size, strength, and upper body power, with no significant between-group differences. There were no significant changes in hormonal concentrations. The results support the use of low volume training for muscular development over a 10-wk period.