Sex Differences in Bench Press Muscle Activation With and Without Pre‐Exhaustion of Triceps Brachii

The aim of this study was to investigate possible sex-differences in upper-body relative strength and the magnitude of muscle activity during the bench press exercise with and without pre-exhaustion (PreEx) of triceps brachii (TB) before the bench press. Resistance trained women (n = 15) and men (n = 15) were assigned to a crossover design where the order of PreEx was block randomized. Each participant completed two 10RM bench press, one without PreEx and one which followed immediately after PreEx to failure with 5 minutes rest in between. Before bench press electromyography electrodes were attached to muscles pectoralis major (PM), TB and deltoideus anterior (DA) and data were normalized to maximum voluntary isometric contraction (%MVIC). For data analyses, a mixed model ANOVA was used. Results showed that both women and men performed a similar number of repetitions in the bench press after PreEx (p = 0.55). A sex-difference was found in TB muscle activation where PreEx before bench press increased TB activation in women (post-hoc p = 0.02) but not in men (post-hoc p = 0.36). Moreover, PM activation increased similarly in women and men (post-hoc p < 0.01 for both) following PreEx, while no changes in DA activation were detected in either sex. During the bench press without PreEx, no sex-differences in muscle activation (%MVIC) were found in any of the three muscles examined. In conclusion, in resistance-trained women, PreEx of the TB enhances activation of both the TB and PM during the bench press, whereas in men, PreEx increases activation only in the PM.