Abstract
Evidence supports the antidepressant effects of resistance exercise training (RET); however, findings among young adults at-risk for elevated depressive symptoms are limited. This randomized controlled trial examined the effects of eight weeks of ecologically-valid, guidelines-based RET, compared to a wait-list control, on depressive symptoms among 55 young adults (26±5y; 36 female) with and without subclinical, or analogue, Generalized Anxiety Disorder (AGAD; Psychiatric Diagnostic Screening Questionnaire GAD subscale ≥6 and Penn State Worry Questionnaire ≥45) and Major Depressive Disorder (AMDD). Following a three-week familiarization period, participants completed one-on-one, twice-weekly RET sessions. The 16-item, self-reported Quick Inventory of Depressive Symptomatology (QIDS) assessed depressive symptoms. RM-ANCOVAs examined between-group differences, and significant interactions were decomposed with simple effects analysis. Hedges' d effect sizes (95%CI) quantified the magnitude of differences in change between groups across time. Stratified analyses were conducted among subsamples with AMDD and AGAD. There were no baseline depressive symptom differences between groups. Attendance was 83%, and compliance was 80%. RET induced statistically significant, clinically-meaningful, large-magnitude reductions in depressive symptoms from baseline to week eight in the total (d = 1.01; [95%CI: 0.44-1.57]), AMDD (d = 1.71; [95%CI: 0.96-2.46]), and AGAD (d = 1.39; [95%CI: 0.55-2.24]) samples. These findings support guidelines-based RET as a promising treatment for mild depression.