Effects of Leisure and Non-Leisure Physical Activity on Mortality in U.S. Adults over Two Decades

Purpose To estimate the effects of the components of total physical activity, leisure-time and non-leisure activity, on all-cause mortality over two decades in a large, nationally representative sample of U.S. adults. Methods We used the first National Health and Nutrition Examination Survey (NHANES I, 1971–1975) and its Epidemiologic Followup Study (NHEFS), which tracked deaths of NHANES I participants through 1992. Using multivariable Cox regression, and multiple imputation for missing values of control variables, we related baseline leisure-time and non-leisure physical activity to all-cause mortality during follow-up, controlling for other risk factors. Adults 35 through 59 years of age (N = 5884) and 60 through 74 years of age (N = 4590) were analyzed separately. Results For persons aged 35–59, moderate non-leisure activity at baseline significantly reduced mortality risk over the next two decades by about 26%, high non-leisure activity by about 37%, compared with low non-leisure activity. For persons 60–74, risk reductions were 34% and 38%, respectively. Leisure-time activity was associated with lower mortality, but was not consistently significant when both types of activity were entered in the regressions. Conclusions Over two decades, non-leisure physical activity was associated with a substantial reduction in all-cause mortality. These results contribute to a growing number of studies that support the importance of measuring all physical activity.