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.
Dept of Sociology, University of Utah, Salt Lake City, UT.
Ming
M
Wen
Lifeng
L
Li
Dejun
D
Su
D000375:Aging / Q000208:ethnology*; D005006:Ethnicity / Q000706:statistics & numerical data*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007407:Interviews as Topic; D007899:Leisure Activities; D008297:Male; D008875:Middle Aged; D009026:Mortality / Q000208:ethnology*; D009043:Motor Activity; D011159:Population Surveillance; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012959:Socioeconomic Factors; D014481:United States / Q000453:epidemiology