OBJECTIVES. Physical activity may be constrained or facilitated by local environments. The
availability of neighborhood facilities for physical activity may be particularly relevant for
youth, who are unable to drive and whose activity is often limited to the immediate distance
they are able to walk or bicycle. Several studies have shown that proximity to recreational
facilities and parks is one of the most important predictors of physical activity. Because the
United States already has an extensive infrastructure of parks, with 70% of adults indicating …