Exercise optional? Researchers find children can stay healthy, avoid obesity by sleeping more

ADELAIDE, Australia — As school vacations near, many parents worry about their kids falling into bad habits during their summer daze. Without school to make sure children are getting their daily physical activity and balanced meals, the job for working moms and dads to keep their youngsters healthy gets even harder. While not every family will have time for extra exercise, a new study finds there are other ways of keeping kids in shape. Researchers from the University of South Australia say children can actually trade physical activity for sleep and still lose weight!

Study authors discovered children can achieve a reduction in body mass index (BMI) by either extra exercise or extra sleep. The surprising results come from a study on how children can maintain good physical and mental health through various “activity trade-offs” during a 24-hour period.

Researchers, partnering with the Murdoch Children’s Research Institute, examined amounts of exercise, sleep, time spent sitting during a child’s day. The team broke down the impact of these three activities on a minute-by-minute basis among 1,179 children between 11 and 12 years-old.

Exercise is still the best way to stay fit

The results reveal moderate-to-vigorous physical exercise is two to six times more beneficial to health than sleep or sedentary behavior. Overall, exercise contributes to a 7.4 percent decrease in BMI among children.

Despite those numbers, study authors also discovered kids can achieve the same exact benefits by sleeping more and sitting less. To reduce BMI and improve physical well-being, researchers say children can:

  • Perform moderate-to-vigorous exercise for 17 more minutes daily
  • Sleep for 52 more minutes each night
  • Reduce their time sitting by 56 minutes a day

To improve mental health however, the team finds children will need to do a little more work — sort of. To significantly boost mental health, the study recommends children exercise for 35 more minutes, sleep for 68 extra minutes, or spend 54 fewer minutes sitting.

Busy families can still live healthy lives

Data on the children comes from the cross-sectional Child Health CheckPoint Study. Researchers measured the physical well-being of each participant by examining BMI, waist size, and body fat levels. For the group’s mental health, study authors looked at each child’s responses to the Pediatric Quality of Life Inventory survey.

Lead researcher Dr. Dot Dumuid says families have a lot on their plates each day. Despite this, there are still ways to keep kids from becoming obese or suffering mentally without rearranging their schedules.

“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 seven percent of children are regularly meeting these goals,” Dr. Dumuid says in a university release. “With so many competing priorities and commitments, it’s helpful to know which activities deliver the greatest ‘bang for your buck’.”

“For families with very little available time, small increases in moderate-to-vigorous exercise could be an option to improve children’s health and wellbeing; alternatively an earlier night could equally deliver the same health benefits – importantly, it’s the flexibility that these findings offer that make them so valuable,” Dumuid continues. “Exploring trade-offs between children’s activities is a promising way for families to make healthy choices that suit their regular family schedule.”

The study appears in the journal Pediatrics.