Light Activity Key to Reversing Childhood Obesity, Study Says

New research indicates that light physical activity may be the key to reversing childhood obesity, finding that activities like long walks, household chores, and biking were associated with a larger reduction in total body fat mass than shorter bursts of moderate-to-vigorous exercise.

The study, published in Nature Communications, was conducted by researchers from University of Exeter, University of Finland, University of Bristol, and University of Colorado. Previous research has found a significant link between sedentary lifestyles in children and adolescent obesity. To combat obesity, the World Health Organization recommends at least 60 minutes of moderate-to-vigorous exercise each day. However, according to the study, 80 percent of adolescents fail to meet that number.

For this investigation, researchers sought to better understand the effectiveness of moderate-to-vigorous exercise compared to light activity in reducing fat mass gain. To do so, they used data from the University of Bristol’s Children of the 90s database, which involved 6,059 children monitored from ages 11 to 24. The study measured participants' sedentary time and light and moderate-to-vigorous physical activity using waist-worn accelerometers. Additionally, it collected data on fat mass, skeletal muscle mass, blood markers, and other health indicators.

The findings revealed that light physical activity is up to ten times more effective than moderate-to-vigorous activity in reducing fat mass gain. During the 13-year period, sedentary time increased significantly, while light physical activity decreased. Each minute of light activity was linked to a 3.6-gram reduction in body fat, indicating a substantial impact on overall fat mass reduction. In contrast, moderate-to-vigorous activity showed a minimal effect on fat mass.

“These new findings strongly emphasize that light physical activity may be an unsung hero in preventing fat mass obesity from early life,” said Andrew Agbaje, MD, of the University of Exeter. “It is about time the world replaced the mantra of ‘an average of 60 minutes a day of moderate-to-vigorous physical activity’ with ‘at least 3 hours a day of light physical activity’. Light physical activity appears to be the antidote to the catastrophic effect of sedentary time in the young population.”

According to Dr. Agbaje, these results indicate that healthcare guidelines and institutions should focus more on light activity than moderate-to-vigorous exercise to prevent fat gain.

“Our study provides novel information that would be useful in updating future health guidelines and policy statements,” he said. “Public health experts, health policymakers, health journalists and bloggers, pediatricians, and parents should encourage continued and sustained participation in light physical activity to prevent childhood obesity.”