SAN FRANCISCO (FRONTLINE MEDICAL NEWS) – The behavioral characteristic that correlated the most with obesity in school-age children was being active less than 1 hour per day, according to findings from a prospective study.

Meredith Johnston, DO, of Eau Claire Cooperative in Columbia, S.C., performed the study with Nirupma Sharma, MD, at Children’s Hospital of Georgia in Augusta. The prospective, questionnaire-based study was conducted with 103 children, aged 5-18 years, over a 6-month period. Dr. Johnston reported the results in a poster presentation at the annual meeting of the American Academy of Pediatrics.

Being active less than 1 hour per day was significantly associated with a higher body mass index in children (P = .006 for 30 minutes to 1 hour, and P = .017 for less than 30 minutes).

“Giving a child one modifiable lifestyle factor to incorporate into their lifestyle instead of overwhelming them with multiple changes is more likely to produce significant change to prevent obesity,” Dr. Johnston said in an interview. “And finding an activity that the child enjoys will produce the best adherence and greatest long-term effects.”

Considering the findings of the study, “children should exercise 30 minutes to 1 hour a day to prevent childhood obesity,” she explained.

A recent review in the Annual Review of Public Health has shown a change in teen physical activity patterns due to an increase in screen time and a decrease in opportunities for physical activities at school and in the community. Giving patients tools for exercise such as dancing to YouTube videos or playing active video games might be a good idea, Dr. Johnston said.

Drinking more than five cans of soda in a day also was significantly associated with a higher BMI (P = .001). That lifestyle factor could be addressed at subsequent well-child visits.

Such efforts are critical, she noted, because an estimated 17% of 2- to 19-year-olds are obese, and 15% are overweight.

Dr. Johnston said she had no relevant financial disclosures.