This national Canadian study examined the associations between several features ofthe neighbourhood built environment and physical inactivity in youth and estimatedthe proportion of physical inactivity within the youth population that isattributable to neighbourhood built environment features. Neighbourhood walkability,density of cul-de-sacs, and park space were independently related to physicalinactivity, although these associations were modest in strength. Nonetheless,because the prevalence of youth residing in non-ideal neighbourhoods was high, ahigh proportion of physical inactivity within the population was attributable tothese three neighbourhood built environment features.
A key difference in the current study and previous studies examining the associationsbetween the neighbourhood built environment and physical activity within youth isthat our study considered multiple built environment features and involved ageographically diverse sample from across the country. Previous studies did notsimultaneously examine all relevant built environment features and typically studiedsmall samples from small geographic regions (e.g., a single city).
The relationship between walkability and total physical inactivity observed in thisstudy and some other studies of youth [49–51] is opposite to what has been shown in adults [52, 53]. Adults from neighbourhoods with greater walkability have higher totalphysical activity levels than adults from neighbourhoods with a lower walkability , while youth from neighbourhoods with greater walkability have lowertotal physical activity levels than youth from neighbourhoods with a lowerwalkability [49–51]. The opposite patterns observed for adults and youth is likely explainedby the different forms of activity that they tend to engage in. While activetransportation is the most common method in which adults engage in physical activity , it only accounts for a small proportion of youths’ total physicalactivity [55, 56]. A much greater proportion of youths’ total physical activity ismade up of active play and organized sport . As such, the negative relationship between neighbourhood walkability andtotal physical activity in youth reported here and in other studies may reflect thatfeatures of highly walkable neighbourhoods inhibit active play and/or sport. Theremay be greater traffic and safety concerns in highly walkable urban neighbourhoodswhere the streets and houses are tightly packed together (left panel ofFigure 1) which may act as a barrier for youth to gooutside and engage in sport and play as they might do in less busy and populatedareas . Indeed, in our study sample perceptions around heavy traffic and itbeing unsafe in the neighbourhood for young children to play outdoors were slightlymore prominent in the most walkable neighbourhoods (data not shown).
Although neighbourhood parks and public green spaces provide a freely accessiblespace for youth to be active, such space was not independently associated withphysical inactivity in the present study. Thus, while park space appears toinfluence the physical activity and body weight of younger children (e.g.,<12 years old) [15, 38], the results from this and other studies [20, 58, 59] suggest that this is not the case in older children and adolescents.Indeed, park users are primarily younger children and older adults [38, 60], and the amenities in most neighbourhood parks (e.g., monkey bars,slides, swings, etc.) are better suited to younger children than to adolescents . Adolescents may travel outside of their home neighbourhood to usecommunity parks with courts and fields, as these amenities are more suitable for thetypes of activities they engage in .
Many youth engage in physical activity in public spaces designed for motorizedvehicles such as streets and parking lots . Our findings suggest that the risk of physical inactivity is increasedby 30% for youth residing in a neighbourhood with a low density of cul-de-sacs.Similar associations have been found in the US and Australia [20, 56]. Cul-de-sacs may encourage physical activity by providing an open areafor youth to participate in unorganized sport and play (e.g., street hockey, catch,skateboarding) in close proximity to their home.
Consistent with our findings, a recent literature review concluded that thenumber/density of neighbourhood recreational facilities, as measured objectivelyusing GIS, is not associated with physical activity in youth . Aspects such as fees, quality, and accessibility of these facilities maybe more relevant for adolescent use than presence alone . Furthermore, recreational facilities may be more important at thecommunity level than at the neighbourhood level. That is, youth are often drivenoutside of their neighbourhood to participate in organized team and club sportsoccurring at facilities in other areas of their extended community .
Previous studies examining the relationship between neighbourhood aesthetics andphysical activity in youth have reported positive [25, 26, 63], negative , and null [65, 66] associations. Thus, as suggested by our findings, there does not appearto be a clear and consistent effect of aesthetics on physical activity within youth.Youth living in aesthetically unpleasant neighbourhoods may become immune to itsaesthetic features, and such features of the environment may not be responsible fordeterring physical activity .
The PAR% values for physical inactivity for the three neighbourhood built environmentfeatures independently associated with physical inactivity were 23% for moderate orhigh walkability, 16% for low cul-de-sac density, and 15% for a moderate amount ofpark space. This suggests that the neighbourhood built environment has a meaningfulimpact on youths’ physical inactivity at the population level. This alsosuggests that these three built environment features would be key targets if theonly goal was to improve youths’ physical activity levels. However, asdiscussed above, these built environment features appear to impact physical activitydifferently in adults, youth, and children. Thus, it will be challenging to optimizethe built environment for the entire population. For example, optimizing streetconnectivity and walkability to increase physical activity within adults may have anadverse impact on youths’ total physical activity levels. An alternative thatmay suit all ages would be to design neighbourhoods with poorly connected streetnetworks and lots of cul-de-sacs, but with well-connected walking and cyclingpathways integrated into the design to facilitate active transportation . Future built environment research that simultaneously studies adults,youth, and children is needed.
Key strengths of this study are the use of a large sample of Canadian youth, thesimultaneous consideration of multiple built environment features, and thegeneralizability of the study methodology. While the findings may only be relevantfor Canadian youth living in close proximity to their schools, the use ofcontemporary statistical modeling, the population attributable risk, and thesimultaneous investigation of multiple built environment features is novel.
There are several limitations of this study. The use of a questionnaire to assessphysical activity may have led to misclassification of this behaviour as youth tendto misreport activity levels [68, 69]. It is likely that this measurement error was non-differential and wouldhave led to underestimated RR and PAR% estimates. Secondly, GIS databases are notalways up-to-date, which would have further contributed to non-differentialmisclassification. Third, this was a cross-sectional study, and therefore we cannotbe certain that the observed relations were causal in nature. However, given thatyouth have limited autonomy in determining where they live, this study was likelynot susceptible to reverse causality. Fourth, we did not assess the presence ofbackyards and driveways at the home, and therefore we may not have fully capturedall aspects of the neighbourhood built environment that may influence youths’physical activity. Fifth, participants were assigned to school neighbourhoods basedon the place where they reported that they lived most often; we were not able toaccount for the fact that some youth may split their time in different homes.Finally, the 2010 Canadian HBSC survey was primarily completed in the colder monthsof the year when physical activity levels are at their lowest , and this may have impacted the associations that were observed.