With a resounding 'Duh ' comes this report based on a NEJM article - Girls stop exercising in teen years.

The study did not ask the girls why they were not exercising.

“Is it they think it’s less cool? They’re more interested in shopping? Does it seem like more of a tomboy-is activity? These are all interesting questions worth pursuing,” said Eva Obarzanek, a research nutritionist at the National Heart, Lung and Blood Institute, which funded the study.

The girls’ decline in physical activity was affected by lower levels of parental education, heavier weight, smoking and pregnancy. Girls with better-educated parents may be better informed and more encouraged to exercise, the researchers suggested.

The investigators also indicate to the reporter that obesity doubled during the teen years. What I find most disturbing is the inverse association of parental education with exericise. We have a de facto social class system (as does every country with which I am aware). How can we provide equal opportunity when a fundamental factor (parental education) puts children at such a life disadvantage? Should we do more in the schools? Would it help?