BACKGROUND Increasing emphasis has been placed on improving physical activity levels through multilevel interventions. This study aims to examine moderating effects of neighborhood safety (crime and traffic) and social support (from parent and sibling/peer) for physical activity in the relationship between the built environment and moderate-to-vigorous physical activity (MVPA) outside school hours among adolescents in Melbourne. METHODS Data were from the NEighbourhood Activity in Youth study conducted among adolescents in Melbourne, Australia (n = 358, 15.3 (SD = 1.5) years). MVPA outside school hours was assessed by accelerometer. Built environment features within 1 km and 2 km residential buffers including recreation facilities, park area, and walkability and its components were assessed using Geographic Information Systems. Neighborhood safety, social support for physical activity and sociodemographic information were self-reported by adolescents. Multilevel linear regression models were used to estimate associations. RESULTS Support for physical activity from sibling/peer positively moderated the relationship between recreation facilities (1 km), residential density (2 km) and MVPA. Recreation facility (count within 2 km), walkability (1 km and 2 km) and residential density (1 km) had significant positive associations with MVPA outside school hours. CONCLUSION The built environment appeared to have stronger facilitating effects on MVPA among adolescents who had favourable support for physical activity from their sibling or peer. Multilevel interventions that target the built environment and social factors are needed to promote MVPA outside school hours among adolescents.

中文翻译：

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青少年的建筑环境和体育活动：邻里安全和社会支持的调节作用。


背景技术越来越重视通过多层次干预来提高身体活动水平。本研究旨在探讨社区安全（犯罪和交通）和社会支持（来自父母和兄弟姐妹/同伴）对体育活动的调节作用，在建筑环境与课外中度至剧烈体育活动（MVPA）之间的关系中在墨尔本的青少年中。方法 数据来自对澳大利亚墨尔本青少年进行的社区青少年活动研究（n = 358，15.3 (SD = 1.5) 岁）。课外时间的 MVPA 通过加速度计进行评估。使用地理信息系统对 1 公里和 2 公里住宅缓冲区内的建筑环境特征（包括娱乐设施、公园区和步行性及其组成部分）进行了评估。青少年自行报告了社区安全、体育活动的社会支持和社会人口统计信息。使用多级线性回归模型来估计关联性。结果 兄弟姐妹/同伴对体育活动的支持正向调节娱乐设施（1 公里）、居住密度（2 公里）和 MVPA 之间的关系。娱乐设施（2 公里以内的计数）、步行能力（1 公里和 2 公里）和居住密度（1 公里）与课外 MVPA 呈显着正相关。结论 对于兄弟姐妹或同龄人对体育活动给予积极支持的青少年来说，建成环境似乎对 MVPA 具有更强的促进作用。需要针对建筑环境和社会因素采取多层次干预措施，以在青少年课外时间推广 MVPA。