Regular physical exercise and its association with depression: A population-based study short title: Exercise and depression

•Stronger association in exercise duration than exercise time in each session is showed.•Regular physical exercise has a low chance of exhibiting symptoms of depression.•Exercise regularly to be relieved from depressive symptoms should be encouraged. This study is to estimate the relation between regular physical exercise and the risk of depressive disorder and depressive symptoms. Data from the Korean Longitudinal Study of Aging (KLoSA) from 2008 to 2018 were used, and 3,070 research samples were included at baseline at 2008. To analyze the relation between physical exercise and risk of depression, a generalized estimating equation (GEE) model and chi-square test were used. The estimate of Center for Epidemiologic Studies Depression (CESD) in those with “< 3 h” of exercise per week was 0.033 higher (95% Confidence Interval [CI]: 0.001 – 0.065 p-value: 0.046) compared to those with “5 h or more” of exercise per week. In terms of exercise duration, the estimates for CESD was 0.153 higher (95% CI: 0.111 – 0.195 p-value: