Residents of highly walkable neighbourhoods in Canadian urban areas do substantially more physical activity: a cross-sectional analysis

Abstract

Background: Research has shown that neighbourhood walkability is associated with small differences in physical activity; however, the health impacts of these small differences have been questioned. We examined the size of the association of walkability with accelerometer-measured physical activity in a large, national-level Canadian population, and compared results to physical activity levels recommended in international guidelines. Our primary objective was to investigate the direction and size of the differences in physical activity that were related to walkability, and whether these differences depended on age. Methods: Participants were included from among respondents to the 2007-2011 Canadian Health Measures Surveys who lived in urban areas and were aged 6-79 years. The Canadian Health Measures Surveys are ongoing cross-sectional surveys of a Canada-wide population. Respondents were divided into quintiles based on Street Smart Walk Score® values of their census dissemination areas. For all respondents and age subgroups, we used covariate-adjusted generalized linear models to estimate differences between quintiles in accelerometer-measured moderate-to-vigorous physical activity (MVPA) and sedentary time. Results: We included 7180 respondents. Differences in participant MVPA between highest and lowest Street Smart Walk Score quintiles were 3.2 (95% confidence interval [CI] -3.2 to 9.6) minutes/day for ages 6-11 years, 11.4 (95% CI 5.3 to 17.4) minutes/day for ages 12-17 years, 9.9 (95% CI 2.4 to 17.4) minutes/day for ages 18-29 years, 14.9 (95% CI 10.2 to 19.6) minutes/day for ages 30-44 years, 11.5 (95% CI 6.7 to 16.3) minutes/day for ages 45-64 years and 6.9 (95% CI 3.1 to 10.8) minutes/day for ages 65-79 years. There were no significant differences in sedentary time in any age group. Interpretation: In all groups except the youngest, participants in the most walkable areas did significantly more MVPA than those in the least walkable areas. For several age groups, this difference was approximately one-half to two-thirds of the amount recommended in guidelines for physical activity. Substantially higher MVPA levels suggest that residents of highly walkable areas may have greater health benefits.