An early night can reduce a child’s weight just as much as exercise

Children playing soccer

Getting extra sleep can reduce a child's weight just as well as exercise, according to a new study.

The research, published in Pediatrics, shows how children can achieve equivalent physical and mental health benefits by choosing different activity trade-offs across the day.

The study, led by the Murdoch Children's Research Institute and the University of South Australia, and supported by the National Heart Foundation of Australia, examined the optimal balance between children's physical activity, sleep, and sedentary time across the 24-hour day to better inform tailored lifestyle choices.

On a minute-for-minute basis, moderate-to-vigorous physical exercise was shown to be 2-6 times more potent than sleep or sedentary time.

While exercise has a greater and faster impact on physical health and wellbeing, children may be able to achieve the same 7.4 per cent reduction in body mass index (BMI) by either:

  • exercising 17 more minutes (moderate-to-vigorous exercise) OR
  • sleeping an extra 52 minutes OR
  • reducing their sitting or sedentary time by an extra 56 minutes

Similarly, children may significantly improve their mental health by either:

  • exercising 35 minutes more (moderate-to-vigorous exercise), OR
  • sleeping an extra 68 minutes OR
  • reducing their sitting or sedentary time by 54 minutes

The study assessed 1179 children aged 11-12 years, from the Child Health CheckPoint Study, which was led by researchers from MCRI.

International guidelines suggest that children need 9-11 hours' sleep, 60 minutes of physical exercise, and no more than two hours of recreational screen time per day, yet only 7 per cent of children are regularly meeting these goals.

The Heart Foundation's Director of Physical Activity, Adjunct Professor Trevor Shilton, said the Heart Foundation was happy to support such an innovative approach to investigating children's physical health and mental wellbeing.

"This study confirms that physical activity is the quickest and most effective way to deliver benefits for children's physical health and mental wellbeing. But the findings also offer some flexibility for families," he said.

"Helping young people make healthy choices and helping families create an environment that supports them in these choices can improve their quality of life in the future, as well as reducing their risk of chronic diseases, such as heart disease."