The Association Between Geographic Information System-Based Neighborhood Built Environmental Factors and Accelerometer-Derived Light-Intensity Physical Activity Across the Lifespan: A Cross-Sectional Study

Background. Evidence on correlates of accelerometer-derived light-intensity physical activity (LPA) is scarce. The aim of this study was to examine associations between Geographic Information System (GIS)-based neighborhood built environmental factors and accelerometer-derived LPA, and to investigate the moderating effect of age group (adolescents, adults, older adults) on these associations. Methods. Objective data were used from three similar observational studies conducted in Ghent (Belgium) between 2007 and 2015. Accelerometer data were collected from 1652 participants, and GIS-based neighborhood built environmental factors (residential density, intersection density, park density, public transport density, entropy index) were calculated using sausage buffers of 500 m and 1000 m around the home addresses of all participants. Linear mixed models were performed to estimate the associations. Results. A small but significant association was observed between residential density (500 m buffer) and LPA in the total sample (B=-0.002; SE=0.0001; p=0.04), demonstrating that every decrease of 1000 dwellings per surface buffer was associated with a two minute increase in LPA. Intersection density, park density, public transport density and entropy index were not related to LPA, and moderating effects of age group were absent. Conclusions. The small association, in combination with other non-significant associations suggests that the neighborhood built environment, as classically measured in moderate-to-vigorous intensity physical activity research, is of limited importance for LPA. More research is needed to unravel how accelerometer-derived LPA is accumulated, and to gain insight into its determinants.