Physical activity as a mediator of the associations between perceived environments and body mass index in Chinese adolescents

• Published in: Health & place 2018-11, Vol.54, p.37-42
• Main Authors: Wang, Jing-jing, Wang, Mei, Lau, Patrick W.C., Ainsworth, Barbara E., He, Gang, Gao, Yang
• Format: Article
• Language: English
• Subjects: Adolescents; Availability; Body mass; Body mass index; Body size; Body weight; Built environments; Children & youth; Environmental aspects; Exercise; Exercise physiology; Health technology assessment; Home environment; Neighborhoods; Obesity; Physical activity; Physical fitness; School environment; Youth
• ISSN: 1353-8292; 1873-2054
• DOI: 10.1016/j.healthplace.2018.09.004

This study examined whether physical activity (PA) mediated the relationships of four PA-related environmental settings (home, school, neighborhood environments and convenient facilities) with body mass index (BMI) among Chinese adolescents aged 13–18 years. Two setting indicators were assessed: (1) perceived availability of environmental resources and (2) perceived importance of environmental resources. Mediation analysis indicated that PA mediated the associations of perceived availability of the home environment, convenient facilities, and perceived importance of the school environment and BMI z-score with ratios of mediating to total effects of 46.2%, 37.1%, and 37.5% respectively. Findings suggest that PA is a mechanism by which several environmental correlates may affect adolescents’ body weight. •PA mediated the association of the home environment on adolescents’ BMI.•PA mediated the association of the convenient facilities on adolescents’ BMI.•School environment was not associated with adolescents’ PA or BMI.•PA mediated the association of perceived importance of the school environment on adolescents’ BMI.•Associations between neighborhood environment in ultra-dense urban cities and PA need further research.