Riding a bike or walking to school 3.5 days or more a week lowered obesity risk by 33 percent compared to those who never bicycled or walked to school, the study found. There was no association between active commuting and a lower risk of being overweight, however.
Drake said it was likely that active commuting just didn't provide enough physical activity to lower the risk of being overweight. The same seemed true of physical education classes.
Another expert, Dana Rofey, an assistant professor of pediatrics and the director of behavioral health at Children's Hospital of Pittsburgh, said, "physical education classes generally aren't consistent enough or long enough to make a difference in the risk of obesity and overweight."
But, even if phys-ed classes are infrequent, "any movement is better than no movement at all," she added.
Because high school sports participation provides moderate to strenuous exercise, the researchers estimated that if all teenagers played on two or more sports teams each year, the rate of obesity would drop by 26 percent. And, if all teens walked or bicycled to school most days, the authors believe obesity would decline by about 22 percent.
Drake suggested trying to get kids involved in sports earlier than high school. "The earlier you start, the more likely you are to stay in it," he said.
And, if your kids aren't natural athletes or especially competitive, he added, "I believe there is an activity our there for every child, and I would encourage parents to let them try many activities," he said. If a child dislikes baseball, maybe ice skating or dance would be better activities, he suggested.
Rofey said for kids who really balk at traditional physical activities, start with just getting them out of the house. Have them volunteer at an animal shelter. Walking dogs isn't strenuous
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