In order to examine the effects of different rest intervals between sets on the training volume completed during a workout, eleven male bodybuilders served as subjects (Mean SD, age= 22±1.4; mass=75±7.6 kg). 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 weeks with four testing session each week. During the first week, one repetition of the maximum (1RM) for the Bench Press (BP), Arm Curls (AC), Military Press (MP) and Leg Press (LP) were tested. Each of the next three weeks included four testing sessions (Saturday, Monday, Wednesday, Friday), during which four sets of exercises were performed with an 85% of 1RM load. During each testing session only one exercise was performed. During each testing session, exercises were performed with a 1, 2, or 5- minute rest interval between the sets. The training volume was defined as the number of repetitions completed over 4-sets and was measured for each rest condition and for each exercise. A statistical analysis was conducted separately for the training volumes in each exercise, and one-way repeated analyses of variance (ANOVA) with the Bonferroni Post Hoc demonstrated the significant differences between the training volume for each rest condition and exercise tested (P<0.05). The 5-minute rest between sets resulted in the highest training volume completed for all exercises, with the 2- and 1- minute rest conditions following in descending order. Our primary results support rest interval length as a strategy for increasing training volume, which is believed to enhance and stimulate greater strength and hypertrophy adaptations. Therefore, for the athletes that were involved in weight training programs in order to improve their maximum strength, it must be noted that rest interval length between sets is a critical component of a resistance-training program and this factor can lead to longer volumes of work.
