Applying GIS in physical activity research: community walkability and walking behaviours.

Physical activity provides many health benefits, including reduced risk of cardiovascular disease, Type II diabetes and some cancers. Environmental exposure factors (e.g., the built environment) are now receiving ever-increasing attention. Large-scale interdisciplinary studies on the association between attributes of local community environments and residents’ physical activity are being conducted. We will focus on findings from Australia - the Physical Activity in Localities and Community Environments (PLACE) study. PLACE is examining factors that may influence the prevalence and the social and spatial distribution of walking for transport and walking for recreation. A stratified two-stage cluster sampling strategy was used to select 32 urban communities (154 census collection districts), classified as high and low ‘walkable’ using a GISbased walkability index (dwelling density, intersection density, net retail area and land use mix) and matched for socio-economic status. We report data on a sub-sample of 1,216 residents who provided information on the perceived attributes of their community environments (e.g., dwelling density, access to services, street connectivity) and weekly minutes of walking for transport and for recreation. Moderate to strong associations were found between GIS indicators of walkability and the corresponding self-report measures. The walkability index explained the same amount of neighborhood-level variance in walking for transport as did the complete set of self-report measures. No significant associations were found with walking for recreation. Relevant GIS-based indices of walkability, for purposes other than transport need to be   developed.