title: Longitudinal relations of perceived availability of neighborhood sport facilities with physical activity in adolescents: an analysis of potential moderators.
abstract: BACKGROUND
  Little is known about the longitudinal relations of environment attributes and leisure-time physical activity (PA) in adolescents, and the moderating effects of individual characteristics. This study examined the longitudinal association of the perceived availability of neighborhood sport facilities with leisure-time PA, and the potential moderating effects of age, past PA behavior, and weight status in adolescents.
  
  
  METHODS
  Among 20,933 follow-up subjects (60.9% of 34,369 baseline subjects), 9993 from 32 Hong Kong secondary schools were successfully matched with baseline (mean duration 16 months; SD 1.7) and had complete information. At baseline and follow-up, respondents reported their leisure-time PA, weight, height, and the presence of sport facilities in the neighborhood.
  
  
  RESULTS
  Increased perceived availability of sport facilities from baseline to follow-up predicted more leisure-time PA at follow-up (β = 1.029; 95% CI: 1.0111.047) overall. This effect was modified by baseline PA, with a significant effect observed only among those who had engaged in leisure-time PA more than 3 times a week.
  
  
  CONCLUSIONS
  Increasing awareness of neighborhood sport facilities or building more such facilities may help active adolescents maintain or increase their leisure-time PA. However, more comprehensive multilevel interventions that aim at enhancing potential social, personal, and environmental PA-related factors may be needed to motivate inactive adolescents.
authors: School of Public Health, Dept of Community Medicine, Hong Kong University, Hong Kong.
authors: Bonny Yee-Man
authors: BY
authors: Wong
authors: Sai-Yin
authors: SY
authors: Ho
authors: Wing-Sze
authors: WS
authors: Lo
authors: Ester
authors: E
authors: Cerin
authors: Kwok-Kei
authors: KK
authors: Mak
authors: Tai-Hing
authors: TH
authors: Lam
mesh_terms: D000293:Adolescent; D000294:Adolescent Behavior / Q000523:psychology*; D004777:Environment; D005260:Female; D006297:Health Services Accessibility; D006723:Hong Kong; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D009043:Motor Activity; D009765:Obesity / Q000517:prevention & control; D010465:Perception; D011159:Population Surveillance; D011633:Public Facilities; D012111:Residence Characteristics; D012931:Social Environment; D013177:Sports