Physical activity and mortality among middle-aged and older adults in the United States

Background: Physical activity (PA) has been routinely linked to lower all-cause mortality, yet extant research in the United States is primarily based on nonrepresentative samples. Evidence is scant on the relative and independent merits of leisure-time (LTPA) versus non-leisure-time (NLTPA) activities and how the PA-mortality link may vary across racial-ethnic-gender groups. Methods: Data were from Health and Retirement Study which began in 1992 collecting data on individuals aged 51-61 years who were subsequently surveyed once every 2 years. The current study assessed group-specific effects of LTPA and NLTPA measured in 1992 on mortality that occurred during the 1992-2008 follow-up period. Cox proportional hazard analyses were performed to examine the PA-mortality link. Results: Net of a wide range of controls, both LTPA and NLTPA showed a gradient negative relation with mortality. No gender-PA interaction effects were evident. Some interaction effects of PA with race-ethnicity were found but they were weak and inconsistent. The mortality reduction effects of PA seemed robust across racial-ethnic-gender groups. Conclusions: Regardless of personal Background, PA is a major health promoting factor and should be encouraged in aging populations. More research is needed to assess relative merits of different types and domains of PA.