Exercise is important for health, but avoiding prolonged periods of sitting is nearly as important. Just get up and move about during the day. The more you move, the greater the health benefits are likely to be.

Each additional hour spent in front of the TV increased the risk of dying from heart disease by 18 percent and the overall risk of death by 11 percent, according to the study, which was published Monday on the Web site of Circulation, an American Heart Association journal.

Prolonged watching of television equals a lot of sitting, which invariably means there’s an absence of muscle movement. If your muscles stay inactive for too long, it can disrupt your metabolism.

What’s more, exercise doesn’t necessarily make up for long sessions in front of the tube. Researchers compared groups of adults who exercised the same amount but watched varying amounts of TV, those who watched more TV were still at a higher risk of dying during the study.

You can be active and also watch high amounts of television. Television isn’t necessarily replacing our exercise time, he explains, but it is replacing everyday, “non-sweaty” movements as basic as standing and walking from room to room. The positive health effects of these seemingly negligible activities are underestimated.

The amount of television a person watches is a good index of the overall time they spend sitting. But there’s also some evidence that watching TV may be unhealthier than other sedentary activities.
Reading or doing homework doesn’t seem to be associated with risk factors as much as television viewing.
It’s the other things you’re doing during television viewing, like snacking.

Studies show that television leads to an increase in the consumption of energy-dense, snack-type foods. It’s a stimulus for poor dietary behavior, whereas some of the other types of sedentary behavior are less likely to stimulate poor snacking behaviors. And because it burns so few calories — about the same as sleeping, hour for hour — watching TV tends to reduce a person’s overall energy output.

The bottom line? Exercise is important for health, but avoiding prolonged periods of sitting is nearly as important. Just get up and move about during the day. The more you move, the greater the health benefits are likely to be.