Importance The 2008 Physical Activity Guidelines for Americans recommended a minimum
of 75 vigorous-intensity or 150 moderate-intensity minutes per week (7.5 metabolic-
equivalent hours per week) of aerobic activity for substantial health benefit and suggested
additional benefits by doing more than double this amount. However, the upper limit of
longevity benefit or possible harm with more physical activity is unclear. Objective To
quantify the dose-response association between leisure time physical activity and mortality …