In order to examine the effects of different rest intervals between sets on the training volume completed during a workout, fifteen male bodybuilders served as subjects (Mean SD, age= 25.28±2.01; mass=73.06±8.33 kg; height=176.33±6.30cm). All of the subjects performed a minimum of 3 strength workouts per week for a period of 2 years. Data collection took place over a period of four sessions with four testing session each week. During the first session, one repetition of the maximum (1RM) for the Bench Press (BP) was tested. Each of the next three sessions included four sets of exercises were performed with a 75% of 1RM load. Rest between sets was randomly assigned from: a timed 3-min rest period; a 1:3 work: rest ratio (1:3 W/R) and achieving a post exercise heart rate of 60% age-predicted maximum (60% Post-HR). The repetitions to exhaustion from set 2 to set 4 were significantly higher in 3-min rest condition than 1:3 W/R and a 60% Post-HR rest conditions (P<0.05), and there is no significant differences between the 60% Post-HR and 1:3 W/R conditions. Within each condition the number of repetitions to exhaustion decreased significantly for each set (P≤ 0.01). Our results showed that 3-min rest interval was more effective method of recovery than the 60% Post-HR and 1:3 W/R conditions during the 4 sets of bench press to exhaustion.
