Abstract
BACKGROUND: In the largely cross-sectional literature, built environment characteristics such as walkability and recreation centres are variably related to physical activity. Subgroup-specific effects could help explain inconsistent findings, yet few studies have compared built environment associations by key characteristics such as sex or life stage. METHODS: Using data from the National Longitudinal Study of Adolescent Health (wave I 1994-5, wave III 2001-2; n=12 701) and a linked geographic information system, cross-sectional relationships between moderate to vigorous physical activity (MVPA) bouts and built and socioeconomic environment measures were estimated. Negative binomial generalised estimating equation regression modelled MVPA as a function of log-transformed environment measures, controlling for individual sociodemographics and testing for interactions with sex and life stage (waves I and III, when respondents were adolescents and young adults, respectively). RESULTS: Higher landscape diversity (coefficient 0.040; 95% CI 0.019 to 0.062) and lower crime (coefficient -0.047; 95% CI -0.071 to -0.022) were related to greater weekly MVPA regardless of sex or life stage. Higher street connectivity was marginally related to lower MVPA (coefficient -0.176; 95% CI -0.357 to 0.005) in females but not males. Pay facilities and public facilities per 10 000 population and median household income were unrelated to MVPA. CONCLUSIONS: Similar relationships between higher MVPA and higher landscape diversity and lower crime rate across sex and life stage suggest that application of these environment features may benefit broad populations. Sex-specific associations for street connectivity may partly account for the variation in findings across studies and have implications for targeting physical activity promotion strategies.