Whether hunching over a computer screen, spending hours behind the wheel of your car, or plopping down on the couch for an evening of television, we all do it. What do all of those things have in common? Sitting! The bad news is that we are more sedentary than any previous generation. In fact, most adults spend over nine hours a day doing sedentary activities. Research shows that long periods of sitting down, even for people who are otherwise physically active, take a toll on your health.