Promoting physical activity to improve the outcome of depression in later life (ACTIVEDEP)

INTERVENTION: Resistance exercise at home 3 times per week (3 sets of 10‐15 reps for each major muscle group) and 150 minutes of aerobic exercise a week (eg, swimming, cycling, walking, or exercise step), usually 30 minutes per day over 5 days during the 12‐week treatment phase. CONDITION: Depressive disorder in adults aged 50 years and older PRIMARY OUTCOME: 50% reduction in the scores of the Montgomery‐Asberg Depression Rating Scale (MADRS) Remission of symptoms (no longer meeting criteria for depressive episode), as established by a formal diagnostic telephone interview using the module for current major depressive disorder from the Structured Clinical Interview for DSM‐IV‐TR Research Version (SCID), between baseline and week 12 of the intervention. SECONDARY OUTCOME: Change in participants' level of physical activity as measured by the Community Healthy Activities Model Program for Seniors (CHAMPS) questionnaire Change in physiological measures ‐ Functional Reach Test, Timed Chair Stand, Timed Up and Go, Cardiorespiratory Capacity INCLUSION CRITERIA: ‐ age 50 years or over, of either sex ‐ meet Diagnostic and Statistical Manual of Mental Disorders (4th Edition) (DSM‐IV) criteria for the diagnosis of major depressive episode within the context of a depressive disorder ‐ fluent in written and spoken English