Association of objectively measured and perceived environment with accelerometer-based physical activity and cycling : a Swiss population-based cross-sectional study of children

We tested whether objectively assessed neighbourhood characteristics are associated with moderate-to vigorous physical activity (MVPA) and cycling in Swiss children and adolescents and assessed the mediating role of the perception of the environment.; The cross-sectional analyses were based on data of 1306 participants aged 6-16 years of the population-based SOPHYA study. MVPA was measured by accelerometry, time spent cycling and the perceived environment by questionnaire. Objective environmental parameters at the residential address were GIS derived. In all analyses, personal, social and environmental factors were considered.; MVPA showed significant positive associations with perceived personal safety and perceived access to green spaces but not with respective objective parameters. Objectively assessed main street density and shorter distance to the next public transport were associated with less cycling in adolescents. Parents' perceptions did not mediate the observed associations of the objectively assessed environment with MVPA and cycling.; Associations between the environment and physical activity differ by domain. In spatial planning efforts to improve objective environments should be complemented with efforts to increase parental sense of security.