Too much screen time may be worse for girls

January 7, 2009 The study in the American Journal of Preventive medicine finds teenaged girls who spend more than two hours of screen time a day watching TV, surfing the web or text messaging are less likely to be physically fit.

Boys who were part of the same study were more likely to be able to sit and still be fit.

Researchers theorize boys may be less affected because their growth spurts have led to sufficient muscle mass. That enables them to maintain fitness and still engage in a large amount of sedentary behavior.