The Autoregulation Rest-Redistribution Training Method Mitigates Sex Differences in Neuromuscular and Perceived Fatigue During Resistance Training.

Abstract

To examine the sex differences in performance and perceived fatigue during resistance training prescribed using traditional (TRA) and autoregulation rest-redistribution training (ARRT) approaches. Twelve resistance-trained men and 12 women completed 2 sessions including the bench-press exercise matched for load (75% of 1-repetition maximum), volume (24 repetitions), and total rest (240s). Sessions were performed in a counterbalanced randomized design with TRA consisting of 3 sets of 8 repetitions with 120-second interset rest and ARRT employing a personalized combination of clusters, repetitions per cluster, and between-clusters rest regulated with a 20% velocity-loss threshold. The effects of TRA and ARRT on velocity loss, unilateral isometric peak force, and rating of fatigue (ROF) were compared between sexes. The velocity loss was generally lower during ARRT compared with TRA (-0.47% [0.11%]), with velocity loss being mitigated by ARRT to a greater extent among males compared with females (-0.37% [0.15%]). A smaller unilateral isometric peak force decline was observed after ARRT than TRA among males compared with females (-38.4 [8.4]N). Lower ROF after ARRT than TRA was found among males compared to females (-1.97 [0.55]AU). Additionally, males reported greater ROF than females across both conditions (1.92 [0.53]AU), and ARRT resulted in lower ROF than TRA overall (-0.83 [0.39]AU). The ARRT approach resulted in decreased velocity loss, peak force impairment, and ROF compared with TRA in both sexes. However, male subjects exhibited more pronounced acute within-session benefits from the ARRT method.