Supplemental Material for: Does high-intensity exercise combined with exposure sessions improve treatment outcomes in obsessive-compulsive disorder? A randomized controlled trial in inpatients.

Ninety-seven inpatients with OCD participated in an eight-week exposure-based treatment phase during inpatient care, comprising two sessions per week, and were randomly assigned to either high-intensity exercise (ExpoHI) or low-intensity control (ExpoLI) administered immediately after a standardized exposure and response prevention (ERP) session. OCD severity was assessed using the Yale–Brown Obsessive Compulsive Scale (Y-BOCS) at admission, discharge, and six-month follow-up.

The secondary outcomes included general psychopathological symptoms. </p><p dir="ltr">Results: ExpoHI showed significantly greater reductions in Y-BOCS scores at discharge (between-group difference: −3.14 points, p = .009), corresponding to a moderate-to-large between-group effect size (Cohen’s d = 0.76), which was maintained at the six-month follow-up (p = .030; Cohen’s d = 0.68). Responder rates at discharge were significantly higher in the ExpoHI group (85.4%) than in the ExpoLI group (61.2%) (p = .011), whereas remission rates did not differ between groups.

ExpoHI also showed greater reductions in depressive symptoms at follow-up. </p><p dir="ltr">Conclusions: High-intensity exercise immediately following exposure therapy produced greater reductions in obsessive–compulsive symptoms than the active control condition. These findings suggest that exercise may be a feasible adjunct for exposure-based treatment.</p>