Does self-selection influence the relationship between park availability and physical activity?

Abstract

Objective: Increased proximity to parkland is associated with physical activity (PA). This study explored the extent to which self-selection--the idea that active persons simply seek out neighborhoods more endowed with active resources--influences the relationship between park availability and PA.

Method: In August 2007, measures of parkland availability within 1 km, importance placed on living near parks, and park-based PA participation were assessed for 585 adults in Waterloo, Ontario.

Results: Logistic regression revealed that (i) participants who placed greater importance on neighborhood open space were not more likely to live near more parkland; (ii) both park importance and park space availability were associated with increased, and relatively equal, odds of engaging in at least some park-based PA; and (iii) participants who placed a low importance on living near parks but had a higher amount of park space nearby were significantly more likely to engage in park-based PA than participants who also placed a low importance on parks but had less nearby park space.

Conclusion: The issue of self-selection does not solely account for the relationship frequently observed between park space availability and PA. Future prospective and intervention studies are needed to draw more definitive conclusions about causality.