After tracking almost 9000 people for six years, Australian researchers found that people who watch TV for more than 4 hours a day are “46 percent more likely to die of any cause and 80 percent more likely to die of cardiovascular disease than people who reported spending less than two hours a day”.
Also, the big problem is that exercising won't help too much with this problem. Even if you exercise daily, prolonged sedimentary periods cause problems that are extremely hard to be undone. Put simply, you really should avoid long periods of sitting, even if you're doing something else (most people sit while watching TV though).
