We know a lot about how kids use their time during the school term, both at school and at home, but very little about how they use their time on holidays, when it is harder to access and assess them. The few studies that have been done suggest that on holidays kids are less active, spend more time in front of screens, and more time sedentary. Diet quality also declines, and caloric intake increases. 

As a result, weight increases and fitness declines faster during holidays than during the school terms. In one US study, the entire annual increase in children’s weight occurred over the summer holidays. Some studies suggest that the declines are worse for kids from disadvantaged families, increasing the gap between the rich and the poor.

These effects may be due to the lack of structure that kids experience during the holidays. At school, there are (ideally) programmed activity periods, healthy tuckshop food, and minimal screen time. During the holidays, sporting competitions often stop, there is open access to food in the home, and kids often have unsupervised screen time. The structured day hypothesis may explain relative declines during the holiday period.

Studies have also shown that in general kids who engage in programmed activity during the summer break — holiday camps, activity days, sports — do better than kids who do not. There is a strong holiday camp culture in Europe and North America, but not in Australia. We should also look at empowering parents to keep kids active during the endless summers, and perhaps even at shortening the summer holiday period.