County-level effects of green space access on physical activity.

BACKGROUND Parks and other forms of green space are among the key environmental supports for recreational physical activity. Measurements of green space access have provided mixed results as to the influence of green space access on physical activity. METHODS This cross-sectional study uses a geographical information system (GIS) to examine the relationships between the amount of and distance to green space and county-level (n = 67) moderate and vigorous physical activity (MVPA) in the state of Florida. RESULTS The gross amount of green space in a county (P < .05) and the amount of green space within defined distances of where people live (1/4 mile, P < .01; 1/2 mile, P < .05; 1 mile, P < .01) were positively associated with self-reported levels of MVPA. Distance to the nearest green space and the amount of green space furthest from where people live (10 miles) were not significantly associated with MVPA. All measures were weighted by the population living in census tracts. CONCLUSIONS The results suggest that there is an association between the accessibility created by having more green space closer to home and MVPA, but this holds only for areas up to and including 1 mile from home.