Objectives: We have a limited understanding of the epidemiological association between objectively measured physical activity and depression among older adults. Therefore, the purpose of this study was to examine the association between accelerometer-assessed physical activity and depression symptoms among a nationally representative sample of US older adults.
Methods: Data from the 2005-2006 National Health and Nutrition Examination Survey was used. 708 older adults (65+ years) wore an ActiGraph 7164 accelerometer for at least 4 days, and completed data on the study covariates along with depression, as assessed by the Patient Health Questionnaire-9.
Results: After controlling for age, gender, race-ethnicity, body mass index, marital status, education, comorbidity index, and physical functioning, for every 60-minute increase in light-intensity physical activity, participants were 20% (OR = 0.80; 95% CI: 0.67-0.95; p = 0.01) less likely to be depressed. Moderate-to-vigorous physical activity was also inversely associated with depression (OR = 0.78; 95% CI: 0.64-0.94; p = 0.01).
Conclusion: These findings suggest that promoting physical activity, even light-intensity physical activity, may have positive mental health effects among older adults. Future prospective and experimental studies are warranted.