Changes in Physical Activity and Sedentary Behavior Associated with Exercise Interventions in Depressed Adults

Abstract

PURPOSE: Exercise training programs are beneficial for depression, but less is known about their impact on non-intervention physical activity patterns and sedentary behavior patterns in depressed adults. We determined the extent to which participation in light-, moderate- and vigorous-intensity exercise intervention programs influenced the habitual physical activity and sedentary behavior patterns in depressed adults. METHODS: Accelerometer data were collected pre- and post-treatment from a subset of depressed participants randomized to one of three 12-week exercise intervention programs: light (n=21), moderate (n=25) and vigorous (n=22) exercise. Mixed models examined changes in accelerometer-measured overall time spent in sedentary, light and moderate-to-vigorous physical activity (MVPA); accumulated sedentary and MVPA bouts; and number of MVPA bouts and interruptions in sedentary time. RESULTS: Overall sedentary time decreased while overall light activity increased across all intervention groups but neither significantly so. The light exercise intervention group reduced their MVPA minutes (-8.22, 95% CI: -16.44, -0.01), time in MVPA bouts (-8.44, 95% CI: -14.27, -2.62), and number of activity bouts (-0.43, 95% CI: -0.77, -0.09). The moderate exercise intervention group reduced the time in MVPA bouts (-6.27, 95% CI: -11.71, -0.82) and number of sedentary interruptions (-5.79, 95% CI: -9.11, -2.46). No changes were observed for the vigorous exercise intervention group. CONCLUSIONS: On the whole, participating in a structured exercise intervention did not lead people who are affected by depression to significantly reduce their overall light physical activity nor to increase their sedentary time. Participation in the light and moderate exercise intervention programs was associated with reductions in overall MVPA, but this was not evident for the vigorous exercise intervention program.