Acute bench press performance responses to two inter-set rest periods in recreationally trained men and women.

BACKGROUND In resistance training, inter-set rest defines training stress and influences fatigue, muscle recovery and the sustainability of force output in subsequent sets. Therefore, this investigation compared acute performance responses and kinematic and kinetic measures between men and women in the bench press exercise with two different rest intervals.

METHODS Twenty-two recreationally trained men and women (age 24.6±2.3 years, height 170.6±7.5 cm, body mass 71.9±11.3 kg) were assigned four sets of 8 repetitions in the bench press exercise with 75% of one-repetition maximum with one- and two minutes of rest between sets in a randomized, cross-over design study. During the exercise, we used a linear position transducer for kinetic and kinematic data acquisition. A 2x4 chi-square (contingency table) and 2x4 Mixed (between-within) ANOVA were used for statistical comparison with a significance level of P<0.05 to determine differences in the datasets.

RESULTS Men and women performed different number of repetitions for the one-minute rest period (chi-square = 13.43572, P=0.003784). Significant interactions were detected in the mechanical work performed for both rest periods (P=0.000026 and P=0.27275 for one-min and two-min), indicating a dissimilar trend in men and women across the sets. While average power declined significantly in both sexes as the sets progressed (P=0.000002 and P=0.000000 for one-min and two-min rest respectively), women were better in maintaining power output both in the one-min (P=0.000056) and the two-min (P=0.013725) conditions.

CONCLUSIONS Compared to males, female trainees are better in maintaining acute bench press performance over multiple sets in a typical hypertrophy workout session.