Sex Differences in the Temporal Recovery of Neuromuscular Function Following Resistance Training in Resistance Trained Men and Women 18 to 35 Years

Abstract

To investigate sex differences in the temporal recovery of neuromuscular function following resistance training (RT), eleven men and eight women 18–35 years completed a single RT bout (barbell back-squats, 80 % 1RM, 5 sets × 5 reps, 25 % duty cycle, then 1 set × max reps). Measures of muscle function (isometric, concentric, eccentric knee extensor strength, and countermovement jump (CMJ) height), serum creatine kinase activity (CK) and lower-body muscle pain were assessed before RT (0 h), +4 h, +24 h, +48 h, and +72 h post-RT. Data are mean % change from PRE (SD) and effect size (ω2, d). Men and women had similar RT-experience (men, 2.1 (0.8) years vs. women 2.4 (1.0) years, P = 0.746, and d = 0.3) and 1RM strength per kg lean mass (men, 1.9 (0.2) kg⋅kg-1 vs. women, 1.8 (0.3) kg⋅kg-1, P = 0.303, and d = 0.3). A 36 (12)% increase in lower-body muscle pain was reported following RT (P < 0.05, d > 0.9). There was an absence of any overt change in CK [+24 h, 74 (41) IU⋅L-1; pooled mean (SD)]. Decrements in knee extensor strength and CMJ height were observed +4 to +72 h for both men and women (P < 0.05, ω2 = 0.19–0.69). Sex differences were apparent for CMJ height (+24 h men, -10 (6)% vs. women, -20 (11)%, P < 0.001, and d = 1.8) and isokinetic concentric strength (+24 h men, -10 (13)% vs. women -25 (14)%, P = 0.006, and d = 1.8), with a more pronounced loss and prolonged recovery in women compared to men (e.g., CMJ + 72 h men, -3 (6)% vs. women, -13 (12)%, P = 0.051, and d = 1.1). We conclude that the different temporal recovery patterns between men and women are not explicable by differences in muscle strength, RT performance, experience, muscle damage or fatigability.

A strength-oriented exercise session required more recovery time than a power-oriented exercise session with equal work

“…Small to trivial impairments of neuromuscular performance were observed after both the exercise sessions. More specifically, measures of CMJ and SJ heights and sprint times were reduced by 1–8%, which are at the low end compared to previous studies (∼2–20%; Raastad & Hallen, 2000 ; Howatson, Brandon & Hunter, 2016 ; Raeder et al, 2016 ; Davies, Carson & Jakeman, 2018 ; Hiscock et al, 2018 ). We believe that this discrepancy is because our participants were well trained, and more importantly, they were familiarized with the exercises and tests.…”

Peer Review #1 of "A strength-oriented exercise session required more recovery time than a power-oriented exercise session with equal work (v0.1)"

“…Small to trivial impairments of neuromuscular performance were observed after both the exercise sessions. More specifically, measures of CMJ and SJ heights and sprint times were reduced by 1-8%, which are at the low end compared to previous studies (2-20%; (Raastad and Hallen, 2000;Howatson et al, 2016;Raeder et al, 2016;Davies et al, 2018;Hiscock et al, 2018)). We believe that this discrepancy is because our participants were well trained, and more importantly, they were familiarized with the exercises and tests.…”

Differential Stimulation of Post-Exercise Myofibrillar Protein Synthesis in Humans Following Isonitrogenous, Isocaloric Pre-Exercise Feeding

“…Participants completed sets of 10 barbell back-squats to volitional exhaustion. For the back-squat, participants fixed a loaded barbell (70% 1RM) across the shoulders on the trapezius (above the posterior aspect of the deltoids) and flexed hips and knees until thighs were parallel to the floor, and then extended hips and knees were in an upright standing position [20]. Each repetition was performed at a cadence of 6 s (timed by a metronome or visible timer).…”