CBT+ for Depression

This study investigates the effects of a novel intervention approach, intentionally sequencing aerobic exercise immediately prior to therapy sessions (i.e., cognitive behavioral therapy \[CBT\]) to determine its effects on both specific and common factors underlying the antidepressant effect of CBT (i.e., mechanisms of CBT). To assess the utility of this treatment augmentation, investigators plan to conduct a randomized controlled trial involving 40 adults with Major Depressive Disorder who will watch a nature documentary while either resting quietly (termed 'CalmCBT') or exercising at a moderate intensity ('ActiveCBT') immediately prior to 8 weekly sessions of CBT. It is hypothesized that target CBT mechanisms of antidepressant action (i.e., self-reported working alliance and behavioral activation) will be more effectively engaged by ActiveCBT vs. CalmCBT.