Intensity, frequency, duration, and volume of physical activity and its association with risk of depression in middle- and older-aged Chinese: Evidence from the China Health and Retirement Longitudinal Study, 2015

The general benefit of physical activity (PA) to one's mental health has been widely acknowledged. Nevertheless, the specific type and amount of PA that associates with lower risk of depression in China awaits further investigation. The present study was conducted on middle- and older-aged Chinese population with two objectives: 1) to understand the patterns of PA; 2) to measure the associations between depression and PA at different levels from various aspects.Using data from the China Health and Retirement Longitudinal Study (CHARLS, 2015), we selected 9118 community residents aged 45 years and older. Depressive symptoms were measured by 10-item Center for Epidemiologic Studies (CES-D 10). Multivariate logistic regression model was performed to examine the association between risk of depression and PA from four aspects including intensity, frequency, duration, and volume.Spending 1-2 days/week (OR = 0.58, 95% CI: 0.36, 0.91), less than 30 minutes each time (OR = 0.66, 95% CI: 0.42, 1.03) or 150-299 min/week (OR = 0.49, 95% CI: 0.28, 0.87) on Moderate Physical Activity (MPA) was associated with lower odds of depression in women. Spending 3-5 days/week (OR = 1.98, 95% CI: 1.29, 3.05) or 6-7 days/week (OR = 1.50, 95% CI: 1.07, 2.11), 4 hours and longer each time (OR = 1.65, 95% CI: 1.18, 2.32), 300 min/week or longer (OR = 1.65, 95% CI: 1.22, 2.24) on Vigorous Physical Activity (VPA) in total, or 2250 Metabolic Equivalent of Task (OR = 1.73, 95% CI: 1.26, 2.38) on Moderate-to-Vigorous PA was associated with higher risk of depression in men.The association between depression and PA depended largely on intensity and gender. Lower frequency, shorter duration, and moderate amount of MPA was associated with lower risk of depression in women. Risk of depression was higher in men who spent higher frequency, longer duration, and overlong time on VPA.