I think it has a lot to do with the parents. If kids see parents enjoying exercise, the kids will be inclined to exercise as well. The converse seems to be try also. I work with an overweight guy and his 5 y/o daughter cannot wear a 2 piece bathing suit because she is too big. He also bought her a motorized car to drive to the park a 1/4 mile down a walking path instead of taking a bike. My kids bike to the park