What beneficial effects were maintained following a supervised high intensity interval training intervention among...

High-intensity interval training (HIIT) improves metabolic health, psychiatric symptoms, and functioning in individuals with psychotic disorders. However, research on the maintenance of HIIT benefits is limited. This study examines whether benefits were maintained six months post-supervised HIIT and identifies factors influencing their maintenance. Sixty-six individuals (61% men; 30.73 ± 7.23 years old) with psychotic disorders participated in a 6-month supervised HIIT intervention (T1-T2), followed by a 6-month unsupervised period with free access to exercise facilities (T2-T3). Psychiatric symptoms and functioning were assessed at T1, T2, and T3. To examine the maintenance of supervised HIIT benefits, we used linear mixed model to compare scores between T1 and T3. To identify factors associated with maintenance of supervised HIIT benefits, participants were divided into two groups based on their attendance to T3 assessment. A one-way ANOVA compared these groups on psychiatric symptoms and functioning T2. Benefits on negative (p = 0.01) and general (p = 0.03) symptoms observed at T2 were maintained at T3. Only younger age was significantly associated with HIIT benefit maintenance (p = 0.02). Consistent with prior research, long-term benefits were observed only for negative and general symptoms. Neither functioning nor symptoms predicted maintenance of supervised HIIT benefits. Lack of improvement in functioning may relate to the absence of social components in the PA intervention. Also, missing data on physical activity during the follow-up period limits interpretation. Finally, future studies should assess the role of continued physical activity and social factors in sustaining benefits.