Abstract
BackgroundThere is accumulating evidence supporting the association between neighborhood built environments and adults’ physical activity (PA) and sedentary time (ST); however, few studies have investigated these associations in adolescents. A better understanding of the features of the built environment that encourage PA or ST is therefore of critical importance to promote health and wellbeing in adolescents. The aim of this study was to estimate the associations of GIS-determined and perceived walkability components in individual residential buffer zones with accelerometer-assessed moderate-to-vigorous physical activity (MVPA) and ST in adolescents.MethodsThe Built Environment in Adolescent New Zealanders (BEANZ) study was conducted in two cities (Auckland and Wellington) during the 2013-2014 academic school years. The exposure measures were subjective and objective environmental indices of activity-friendliness using four residential buffers. Road network buffers were calculated around participant’s residential addresses using the sausage buffer approach at 250 m, 500 m, 1 km, and 2 km scales. A 25 m radius was used for the buffers. Data were analysed using Generalized Additive Mixed Models in R.ResultsData were analysed from 524 participants (15.78 ± 1.62 years; 45% male). Participants accumulated ~114 min/day of moderate-to-vigorous PA (MVPA) and ~354 min/day of ST during accelerometer wear-time (~828 min/day). The estimated difference in MVPA between participants with the 1st and 3rd quartiles observed values on the composite subjective environmental index of activity-friendliness (perceived land use mix - diversity, street connectivity and aesthetics) was equivalent to ~8 min/day (~56 MVPA min/week) and for the objective environmental index of activity-friendliness (gross residential density and number of parks within 2 km distance from home) was ~6 min of MVPA/day (~45 MVPA min/week). When both indices were entered in a main-effect model, both indices remained significantly correlated with MVPA with sex as a moderator. The predicted difference in sedentary time between those with the minimum and maximum observed values on the subjective index of non-sedentariness was ~20 min/day.ConclusionsThe combined assessment of the main effects of subjective and objective indices of activity-friendliness on NZ adolescents’ PA and ST showed positive relationships with MVPA for the subjective index only. The subjective index was a significant correlate of PA in both girls and boys, while the objective index was significant only in boys when sex was entered as a moderator. Further research is warranted to understand the relationships of ST with the built environment.
Highlights
There is accumulating evidence supporting the association between neighborhood built environments and adults’ physical activity (PA) and sedentary time (ST); few studies have investigated these associations in adolescents
Evidence suggests that low physical activity (PA) and prevalence of sedentary behaviors in adolescence are negatively associated with adolescent health outcomes such as obesity, cardiovascular illnesses and metabolic disorders [1]
While New Zealand ranked second of 38 countries on the Global Report Cards for PA, approximately one-third of children and youth were insufficiently active for health, and that adolescents accumulated less PA, less active transport, and more sedentary behavior than their younger peers [5]
Summary
There is accumulating evidence supporting the association between neighborhood built environments and adults’ physical activity (PA) and sedentary time (ST); few studies have investigated these associations in adolescents. While New Zealand ranked second of 38 countries on the Global Report Cards for PA, approximately one-third of children and youth were insufficiently active for health, and that adolescents accumulated less PA, less active transport, and more sedentary behavior than their younger peers [5]. When considering the public health implications of these findings, it is important to consider that individually-based behavioral interventions: (1) are only offered to a small portion of the population (study participants) and so have limited reach, (2) affect change in a sub-sample of the study population only, and (3) have long-term effects in an even smaller subsample of the study population. Using the RE-AIM framework (reach, efficacy, adoption, implementation, maintenance [7]) it is clear that behavioral interventions are significantly limited in their ability to cause sustained and meaningful levels of behavioral change across a large portion of the population
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
