Effects of Resistance Exercise on Depressed Mood State: A Randomized Controlled Trial

PURPOSE: This secondary analysis of a randomized controlled trial (RCT) of resistance exercise training (RET) compared with a waitlist quantified the acute effects of a single resistance exercise session on depressed mood state. METHODS: Sixty-two young adults (26.6 ± 5.6 yr; 39 female) were randomized to 8 wk of World Health Organization and American College of Sports Medicine guidelines-based RET or a waitlist, with an acute RCT nested in at week 1. In the first session, RET participants completed moderate-intensity resistance exercise, comprising two sets of 8-12 repetitions of eight exercises targeting the major muscle groups. Waitlist participants completed 30 min of quiet rest. The Depression subscale of the Profile of Mood States Brief Form (POMS-B) measured depressed mood state pre- and 10 min post-session. Two group × two time (pre/post) RMANOVAs examined differences between resistance exercise and quiet rest. Subanalyses were conducted among young adults with analogue generalized anxiety disorder (AGAD), major depressive disorder (AMDD), comorbid AGAD and AMDD, and pre-exercise POMS-B ≥1 and ≥4. RESULTS: No significant group-time interaction ( F(1,59) = 1.70, P = 0.198) was found for depressed mood state. Significant main effects for time were found among the total ( F(1,59) = 14.74, P < 0.001), AGAD ( F(1,28) = 13.22, P ≤ 0.001), AMDD ( F(1,12) = 5.12, P ≤ 0.043), POMS-B ≥1 ( F(1,31) = 30.29, P < 0.001) and ≥4 ( F(1,11) = 10.71, P = 0.007) samples, such that depressed mood state reduced following a single bout of resistance exercise ( d = 0.29 to 1.26) and quiet rest ( d = 0.27 to 0.39). CONCLUSIONS: Resistance exercise and quiet rest elicited significant small-to-large and small-to-moderate magnitude reductions in depressed mood state, respectively, that were not significantly different from each other.