A longitudinal study of children's outside play using family environment and perceived physical environment as predictors.

Background: A natural and cheap way of increasing children's physical activity is stimulating unstructured outside play.

Purpose: This study examined whether characteristics of the family and perceived physical environment were associated with the duration of children's outside play.

Methods: Parents participating in the "Be Active, Eat Right" cluster RCT control group (N = 2007) provided information on potential predictors of outside play (i.e. family and perceived physical environment) of their 5-year-old child by questionnaire. Child outside play was assessed by parental reports both at five and seven years. Linear regression analyses, adjusted for seasonality, were performed to evaluate associations between potential predictors and child outside play. Linear mixed models were fitted to evaluate the relationship between potential predictors and the development of outside play over two years, with season entered as a random factor.

Results: Family environment was the strongest construct predicting child outside play, while parent perceived physical environment had no significant association with child outside play. Parental habit strength and the presence of rules were the strongest predictors of increased outside play. Parent perceived difficulty in improving child outside play was the strongest predictor of decreased outside play.

Conclusion: Family environment predicted child outside play and not perceived physical environment. Parental rules and habit strength regarding improving outside play were associated with an improvement of child's engagement in outside play.