1.) Four fewer hours in the day to exercise.

2.) Four more hours in the day where it's really easy to snack on the sorts of foods that lead to weight gain and hurt your health.If you were asked why watching television for four hours a day increases your risk of dying, you'd probably cite one or both of the reasons above. Your response would make sense because both contribute, but a recent study done in Australia found something else.That watching four or more hours a day of television reduces the total time during the day that you do something that has been linked to a lower incidence of death.Move your body.Before you dismiss this study as one that does nothing more than reassert the obvious, consider the study's most surprising find: that the incidence of a higher death risk in those who watch four or more hours of television a day held true even in a group of people whom you would think would be able to do so without any ill effects: regular exercisers.Yes, even in the regular exercisers among 8,800 people aged 25 and over who took part in the Australian Diabetes, Obesity, and Lifestyle Study, increasing amounts of daily television viewing increased the risk of death, a fact that leads lead author Dr. David Duncan, a researcher at the Baker IDI Heart and Diabetes Institute in Melbourne, to say that it's not a lack of traditional exercise that's hurting our health, but a lack of "incidental moving around, walking around, standing up and utilizing muscles that [doesn't happen] when we're plunked on a couch in front of a television."While previous studies found a correlation between increased television viewing time and the incidence of heart disease, this study is the first to correlate increased television viewing time to all types of death. And it did so rather convincingly.According to a report in Medical News Today, those in the study who watched four or more hours of television a day were 46 percent more likely to die of any cause and 80 percent more likely to die of cardiovascular disease than those in the study watched less than two hours a day.While four or more hours of television viewing a day may seem unusual or extreme, it's not. The Nielsen Company, well known for its television ratings, determined that Americans watched an average of 151 hours a month of television during the fourth quarter of 2008, which equates to about five hours a day.Equally as distressing is that Dunstan and his colleagues believe other sedentary activities, such as working on a computer, playing video games or even reading a book or taking a bus or train increase the risk of death.In related research, Dr. Marc Hamilton, a scientist at Pennington Biomedical Research Center in Baton Rogue, Louisiana, has discovered a concrete reason why long periods of inactivity harm the health. During that time, the body stops pulling fat from the bloodstream to use as energy.As a result, more than normal remains in the bloodstream, increasing the risk of artery damage that can eventually lead to heart disease.From the broken-record departmentWhen mainstream medical advice suggested moderate exercise three to four times a week as a way to safeguard health years ago, I expressed the opinion that more intense exercise is better. And continued to do so.Twice already this year, in fact, I have written columns expressing that sentiment and citing research that suggests it is true.That's why I read with interest and a bit of self-satisfaction rash of articles about the time of the Winter Olympics that suggested shorter, more intense sessions of exercise are not only a smart way for those who are time-crunched to manage to exercise, but also a more effective form of exercise.One study compared people on a typical jogging regiment to those who used interval training as a way to increase intensity and shorten workouts and found that the interval trainers doubled their endurance and increased their strength by more than 10 percent. Their speed also increased five percent.It's results like these that have caused Jan Helgerud, exercise expert at the Norwegian University of Science and Technology, to say, "[Interval training] is like finding a new pill that works twice as well. . . . We should immediately throw out the old way of exercising."Please be advised that those used to more moderate rates of exercise need to add intensity to their workouts gradually and that those beginning or returning to exercise after a period of inactivity should consult a doctor first.