Children's activity and diet behaviours in the summer holidays versus school year

SummaryBackgroundEvidence shows children gain more weight during the summer holidays versus the school year.ObjectivesTo examine within‐child differences in activity and diet behaviours during the summer holidays versus the school year.MethodsChildren (mean age 9.4 years; 37% male) wore accelerometers (GENEActiv; n = 133), reported activities (Multimedia Activity Recall for Children and Adolescents; n = 133) and parents reported child diet (n = 133) at five timepoints over 2 years capturing school and summer holiday values. Mixed‐effects models were used to compare school and summer holiday behaviours.ResultsChildren spent less time in moderate‐ to vigorous‐physical activity (−12 min/day; p = 0.001) and sleep (−12 min/day; p < 0.001) and more time sedentary (+27 min/day; p < 0.001) during summer holidays versus the school year. Screentime (+70 min/day; p < 0.001), domestic/social activities (+43 min/day; p = <0.001), self‐care (+24 min/day; p < 0.001), passive transport (+22 min/day; p = 0.001) and quiet time (+16 min/day; p = 0.012) were higher during the summer holidays, compensating for less time in school‐related activities (−164 min/day; p < 0.001). Diet quality was lower (−4 points; p < 0.001) and children consumed fewer serves of fruit (−0.4 serves; p < 0.001) during the summer holidays versus the school year.ConclusionsChildren are displaying poorer activity and diet behaviours during the summer holidays, which may contribute to accelerated weight gain over the holiday period.