The purpose of the study was to develop an explanatory model of the exercise/depression relationship using a rural-residing population of elderly aged 65 or older. Subjects were selected from the 3,673 persons who participated in the Iowa 65+ Rural Health Study. The 2,084 subjects with complete data, valid information about depressive symptoms, and ability to walk across a small room were divided into two cohort groups at baseline: those with few and those with more depressive symptoms. Logistic regression models using walking status, demographic variables, and chronic health conditions were developed to predict depressive symptoms for this population at a 3-year follow-up. Consistent with previous studies using mixed-age cohorts, physical activity was negatively associated with depressive symptoms. We concluded that the relationship between exercise and depressive symptoms may be manifested in both subjects with more and few depressive symptoms because both groups benefited from daily walking.
K.E. Mobily is with the Department of Sport, Health, Leisure, and Physical Studies, The University of Iowa, Iowa City, IA 52242. L.M. Rubenstein, J.H. Lemke, and R.B. Wallace are with the Department of Preventive Medicine and Environmental Health, and M.W. O’Hara is with the Department of Psychology, The University of Iowa.