Physical inactivity is considered a major public health problem. We analyze participation in physical activity using data from a nationally representative sample of individuals in 1998 and 2000 augmented with additional state-level data on government spending on parks and recreation. We find considerable variation in participation and time spent in physical activity across different groups of physical activity. Spending on parks and recreation increases participation in group sports but reduces participation, and time spent, in walking for exercise, suggesting that parks and recreation spending may not be an effective policy tool for increasing physical activity. (JEL I200, I120, I180, L830)