The research published in the November edition of the journal Obesity looked into 100 overweight children aged 7 to 11 in Augusta, Georgia. A quarter of the kids snored or had other sleep-related breathing problems, reported the online edition of the health magazine WebMD.
The researchers randomly split the kids into three groups. One group got 40 minutes of supervised aerobic exercise - such as tag, basketball, soccer or jump rope - every day for about 13 weeks. Another group got 20 minutes of the same sort of daily aerobic exercise.
For comparison, kids in the third group weren't assigned for any aerobic exercise but were free to continue their usual activities.
After about 13 weeks, the researchers took feedback from the parents on the snoring of the children and their sleep related breathing problems.
The found that kids in the exercise groups had a bigger drop in snoring and sleep-related breathing problems than those not assigned to exercise.
Both exercise groups showed a similar drop in snoring, said Catherine L. Davis her colleagues from the Medical College of Georgia who conducted the study.
But kids assigned to exercise at least 40 minutes a day showed the biggest overall improvement in sleep-related breathing problems, they said.
Since the study included only obese children, it's not clear if the findings apply to kids who aren't overweight, they added.