Abstract

Background: Most children do not meet the physical activity recommendations from the World Health Organization, and there is limited evidence about the associations between school environment factors and physical activity patterns in children.

Aim: The aim of this study was to examine associations between Swedish school children’s physical activity patterns and school environment factors during school hours.

Methods: In this cross-sectional study 312 children from 2^nd grade and 266 children from 5^th grade were invited to participate (aged 8-11 years, from five public elementary schools in Stockholm). 323 (170 girls and 153 boys) children accepted (195 2^nd grade and 128 5^th grade) and provided parental informed consent (56% participation rate). The inclusion criteria were that children must be enrolled in either the 2nd or 5th grade at the time of the study. Physical activity and sedentary time were measured with wrist-worn accelerometers. School environment factors consisted of physical activity policies during school hours, physical activity policies before or after school hours, mobile phone bans during recess, organized physical activity during recess, organized physical activity during lessons, size of the schoolyard (m²/child) and the children’s own perception of the schoolyard opportunities for physical activity. To assess the associations between the school environment factors and physical activity patterns, linear regression was used. P- value of ≤ 0.05 was set as probability level. All models were adjusted for sex, age, body mass index, accelerometer non-wear time, and parental education and school clustering.

Results: The total sample included 278 participants from five schools. The sample was slightly skewed towards girls (52.7%) compared to boys (47.3%) and the mean age was 10.0 years (± 1.5). The prevalence of overweight and obesity was 7.1%. There was a significant association between the size of the schoolyard and minutes spent sedentary for both boys (β = -1.45, 95% CI: -2.64, -0.26) and for girls (β = -1.67, 95% CI: -2.76, -0.57). The results showed significant associations between a physical activity policy during school hours and minutes spent in moderate to vigorous physical activity for boys (β = 13.34, 95% CI:10.66, 16.04), not for girls (β = -1.03, 95% CI: -3.62, 1.57). There was no association between the children’s own perception of opportunities for physical activity and physical activity patterns.

Conclusion: Physical activity policies during school hours are associated with increased levels of moderate to vigorous physical activity in boys, but not girls. Also, increased size of the schoolyard is associated with decreased levels of sedentary time.