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 non-representative 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 to 61 years who were subsequently surveyed once every two years. The present 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.