Outdoor play in children: Associations with objectively-measured physical activity, sedentary behavior and weight status

• The majority of children spend > 1 h/day playing outdoors on weekends (not weekdays).
• Outdoor play is associated with sedentary time, light PA, and MVPA.
• Associations of outdoor play with PA persist for weekdays, weekends, and after-school.
• Outdoor play is inversely associated with being overweight in boys.
• PA of overweight boys who play outdoors for > 2 h/day similar to normal-weight boys

ObjectivesTo determine the amount of time children play outdoors and examine associations with weekday, weekend and after-school physical activity (PA), sedentary behavior (SB), and weight-status (normal-weight, overweight/obese).MethodsData were extracted from Project BEAT (Toronto, 2010–2011; www.beat.utoronto.ca). Children's (n = 856; mean age = 11 ± 0.6 years) PA and SB were measured using accelerometry. Outdoor play (OP) was assessed via parental report and collapsed into three categories (< 1 h/day, 1–2 h/day, > 2 h/day) and differences in anthropometric and PA characteristics were assessed.Results55.1%, 37.2%, and 7.7% of children played outdoors for < 1 h/day, 1–2 h/day and > 2 h/day, respectively, on weekdays. OP was higher on weekends and in boys. OP was associated with SB, light PA and MVPA at all time-points, whereby children attaining < 1 h/day had lower activity profiles. Boys playing outdoors for < 1 h/day were more likely to be overweight/obese and had lower PA levels than normal weight boys. However, overweight/obese boys who spent > 2 h/day playing outdoors had PA profiles similar to normal weight counterparts.ConclusionEncouraging children to spend more time outdoors may be an effective strategy for increasing PA, reducing SB, and preventing excess weight gain (particularly boys' play).