Associations of Residential Density with Adolescents’ Physical Activity in a Rapidly Urbanizing Area of Mainland China

Abstract

In the context of recent social and economic transitions in China, lack of physical activity among adolescents is an emerging health risk, particularly so in rapidly expanding urban areas. Evidence from Western countries suggests that built environment attributes can influence the physical activity participation of young people, but whether or not this is the case for China is unknown. We recruited high school students from ten urban districts in Nanjing, Mainland China (n=2,375; mean age=13.9± 1.0 years old; 46% boys; survey response rate=89%). The outcome variable was selfreported recreational physical activity time; the primary explanatory variable was the residential density of the urban districts. Analysis was conducted using mixed-effects logistic regression models. After adjustment for potential confounding variables, including sedentary behavior and green space, there was a consistent and graduated association between residential density and physical activity; residential density was significantly negatively associated with recreational physical activity time for students from the higher tertile of residential density (OR; 95% CI=0.64; 0.42 to 0.97) compared to those from the lower tertile. The direction and magnitude of the negative association between residential density and physical activity was similar for boys and girls. It should be a public health priority to identify the particular urban environment attributes that can encourage and support young people's participation in physical activity.

Walking, obesity and urban design in Chinese neighborhoods

“…Respondents in these middle income neighborhoods with a lower State of Place™ Index did less walking for various purposes, which may at least partly explain their higher BMIs. Findings also challenged existing research (Xu et al, 2009(Xu et al, , 2010 that linked high density with low levels of (recreational only) physical activity.…”

“…The few empirical studies conducted have produced some counterintuitive findings: in the Chinese context, high density has been associated with reduced recreational physical activity (Xu et al, 2009) and increased overweight (Xu et al, 2010). Extremely high density may limit open space and parks, leaving little space for walking or other physical activity.…”

“…For example, in the studies noted above, the density measure was based on the aggregate of 13 districts within a city of 8 million people (Xu et al, 2009). At this level, the density measure may be capturing confounding effects from some unobserved or unmeasured built environment factors.…”

What is a walkable place? The walkability debate in urban design

“…Many of the aspects of environments perceived to enhance walkability, and which are reviewed elsewhere in this paper, were not found to increase the amount of actual walking (also Bauman et al 2012). Logically, for example, places deemed "walkable" in one definition may be too convenient to allow much exercise (Van Dyck et al 2009a;Lovasi et al 2009;Gebel et al 2009Gebel et al , 2011Xu et al 2010).…”

Healthy Environment and Healthy Living in Urban China: An Emerging Field in Research

“…Adults were the research subjects for three out of four studies. Only one study 32 focused on adolescents. Studies in the US and other developed countries showed that built environmental attributes might have different impacts on adults and children.…”