Performing high-intensity exercise prior to receiving cognitive behavioral therapy (CBT) does not lead to enhanced outcomes in patients with major depressive disorder (MDD); however, improving physical fitness may improve symptom change during CBT. These study findings were published in Journal of Affective Disorders.
Researchers conducted a longitudinal, randomized controlled trial that comprised 120 outpatients (aged 18-65 years) with MDD and mild or moderate depressive symptoms. Participants were recruited with flyers and online advertisements at the Center for Psychotherapy at the Humboldt Universitat zu Berlin in Germany. Researchers included 34 healthy control participants. Anticipating higher dropout rates with physical exercise programs, participants were randomly assigned in a 2:3:3 ratio into a waiting list control group (WL; n=30), a high-intensity exercise group (HEX; n=45), or low-intensity exercise group (LEX; n=45), respectively. Participants then underwent 12 weeks of exercise training or waiting before all patients received manual-assisted CBT.
Participants were unblinded to group allocation by waiting list or exercise while blinded to specific exercise allocation. CBT therapists were blinded whereas exercise instructors were unblinded. Exclusion criteria included suicidal ideation, borderline or antisocial personality disorder, severe depressive symptoms, body mass index less than 18 kg/m2 or greater than 35 kg/m2, and the use of beta-blockers or benzodiazepines within the previous week.
At baseline, participants with MDD were well-matched in sex, age, education, and fitness with healthy control participants. Participants with MDD had higher dysfunctional attitudes, global severity of mental health problems, depressive symptoms, and lower reported physical activity than the healthy control participants at baseline.
A total of 75 participants completed the waiting period or exercise program and CBT (WL, n=23; HEX, n=22; LEX, n=30). Dropout rate was greater among women (42.6%) than in men (25.4%). After the 12 weeks, no changes were observed in physical fitness in LEX or in WL; physical fitness did improve in HEX. From baseline to post-CBT, all groups saw improvement in depressive symptoms. Depressive symptoms improved significantly in all 3 groups, but there was no statistical significance in improvement comparing groups. The researchers found the amount of improvement in fitness predicted the following CBT response according to regression analyses.
Study limitations include the high dropout rate, preparatory CBT sessions may have influenced depressive symptoms prior to post-CBT assessment, participant bias toward CBT, and participants with severe MDD not included.
Study authors concluded, “While depressive symptoms improved significantly following exercise treatment in the HEX as hypothesized, a comparable response was found also in the LEX and WL groups, unexpectedly. Also, after a subsequent CBT, no mean differences in depressive symptoms were detected between groups.” Because regression analysis revealed the amount of individual improvement in fitness predicted subsequent CBT response, they suggest future studies assess personalized training programs.
Heinzel S, Schwefel M, Sanchez A, et al. Physical exercise training as preceding treatment to cognitive behavioral therapy in mild to moderate major depressive disorder: a randomized controlled trial. J Affect Disord. Published online September 14, 2022. doi:10.1016/j.jad.2022.09.024