Study Shows Benefits of Exercise on Children’s Sleep

Onefourth of overweight children may have sleep problems that regular physical activity can largely resolve, researchers say. Research published in the November 2006 issue of Obesity shows a surprising 25 out of 100 overweight, inactive children tested positive for sleepdisordered breathing, including telltale snoring. After about three months of vigorous afterschool exercise, the number of children who tested positive for a sleep disorder was cut in half, according to Dr. Catherine L. Davis. In children who exercised the longest, the number was reduced by 80 percent. The children were among 100 boys and girls age 7 to 11 enrolled in a study of the effects of exercise on metabolism. For that study, the children were divided into three groups: a control group, a group that exercised 20 minutes daily and one that exercised 40 minutes daily. Researchers found the average score for all children who exercised improved on the Pediatric Sleep Questionnaire.

“Existing data suggest about 2 percent of children have sleep problems, but with 37 percent of children now considered overweight, the percentage may be much higher,” said Dr. Davis, an MCG clinical health psychologist and the study’s first author.

“We believe this study is a red flag to pediatricians to ask parents about their children’s snoring,” she said. “Not sleeping well can affect behavior and the ability to function in school. We don’t know yet if it affects development.” “The longterm consequences of sleepdisordered breathing on children are unknown,” the study authors wrote. “There may be lasting benefits of prevention or amelioration of sleepdisordered breathing as a result of protection from neural insult during childhood.” Dr. Davis likens sleepdisordered breathing in children to the increasing incidence of lifestylerelated type 2 diabetes. “Nobody used to think type 2 diabetes happened in kids, either,” said Dr. Davis, who studies the impact of exercise on the risk of the disease in children. “We thought type 2 diabetes was something you got at maybe 50, not 15. It has become a major media sensation because it is so shocking.” When Georgia researchers first gave the Pediatric Sleep Questionnaire to parents, they were surprised by how many children tested positive for symptoms including snoring, loud breathing and daytime inattentiveness. Interestingly, sleepiness was not an issue; sleepdeprived children are more likely to be hyperactive than listless. Caffeine may also subvert sleepiness, the researchers said. To learn more about sleep patterns in overweight children, Dr. Davis has started a similar study using wristbands to record movement during sleep and fingertip pulse oximeters to measure oxygen levels.

Dr. Amy R. Blanchard, pulmonologist and director of the MCG Georgia Sleep Center, is working with Dr. Davis on the new study and hopes their monitoring approach