I agree. When I was a kid, we played football or soccer in the fall, basketball in the winter, baseball in the spring and maybe kickball or whiffleball over the summer (though we were more likely riding our bikes all over town, looking for trouble.) But these days, the kids play their sport during the sport's traditional season. Then they play the same sport for a club/travel team in the off season. And then, during whatever time that's left, they go to camps, clinics, and clubs to get further reps/practice on that same sport. They're using the same muscles in the same way all year round, and its causing injuries. My anectdotal evidence? My daughter plays varsity volleyball. Lots of girls popping advil (vitamin A) before every game. That shouldn't be normal for 17 year old girls.