Randomised controlled trials (RCTs) or quasi-experimental studies of exercise (delivered by someone specifically trained to deliver it) versus control in participants aged over 60 years with depressive symptoms (diagnosed by a physician interview, standardised mood measure or treating clinician) were eligible for inclusion. The exercise intervention could be a component or sole intervention. Studies had to enrol at least 80% of participants aged over 60 years and had to report appropriate outcome measures. Participants with dementia were excluded. Studies were excluded if they did not include participants who were depressed at enrolment.
The included trials studied walking, aerobics, Tai Chi, qigong and weight bearing or progressive resistance training in depressed outpatients with a mean age ranging from 65 to 82.4 years. Exercise intensity ranged from 20 to 60 minutes, typically three times per week for between six and 19 weeks. The primary outcome was the effect of exercise on depression as measured by Diagnostic and Statistical Manual of Mental Disorders IV (DSM-IV), Hamilton Rating Scale for Depression (HRS), Centre for Epidemiological Studies Depression Scale (CES-D), Geriatric Depression Scale (GDS) and Beck Depression Inventory (BDI). Participants were diagnosed with depression using DSM-IV, HRS, CES-D, GDS, and BDI. The proportion of males ranged from 50% to 81.6%.
The authors did not state how many reviewers performed study selection.