) -- Kids can pass a lot of things around to each other -- germs, colds, a bad case of the giggles. Now, new research suggests that their activity levels, too, may be contagious.
A study from Vanderbilt University found that when children have friends that are more active they themselves are also likely to be more active.
Moreover, when children have close friends that regularly engage in vigorous activity they will try to keep up.
Eighty-one children between the ages of 5 and 12 were enrolled in two afterschool programs and followed over 12 weeks. During that time children were asked with whom they were friends, and their level of activity was measured using a device called an accelerometer.
The findings showed that when kids were playing with others who had higher level of activity, they were more likely to increase their own levels of physical activity.
"They have conducted hundreds of trials across the nation that has not changed kids eating behavior," said Sabina Gesell, professor of pediatrics at Vanderbilt University School of Medicine in Nashville, Tenn. and lead study author.
"We needed a new novel approach... In order to move our intervention against obesity to a new level," Gesell said. "Now we have the evidence to move forward."
Other pediatric experts agree with these findings.
"I've noticed that the more active a social network kids have, the more likely they are to be physically active," said Keith Ayoob, associate professor in the Department of Pediatrics at Albert Einstein College of Medicine in New York. "Socializing is a happy thing for kids and it prevents boredom."
Dr. Malissa J. Wood, assistant professor of medicine Harvard Medical School, is an expert in the effect of social connections on healthy behaviors. She said that the study suggests a plan of action for parents who would like to see their children adopt healthier behaviors.
"Individuals adjust behavior to have stronger connections with those whom they care about," she said. "By encouraging the active children to become 'champions' or agents of change for their peer group allows them to develop leadership skills at a young age and to positively influence their less active friends."
Gesell said it is encouraging that the foundation is already laid for implementing more physical activity for children.
"After-school programs across the country exist, there is a model in place so it could be very sustainable on large scale that is exciting," Gesell said.
But most important, she said, is for children to associate with peer groups in which physical activity is the norm.
"Peer groups matter," Gesell said. "If your child is surrounding by children who are sedentary it will be difficult for that child to be more active. If they can find more active friends it will be easy to change their activity level."