Couch Potato Nation: Nearly half of Americans sit for far too many hours a day and don’t get any exercise at all, a new study finds. A survey of some 5,900 adults found that nearly 26 percent sit for more than eight hours a day, 45 percent don’t get any moderate or vigorous exercise during the week, and about 11 percent sit more than eight hours a day and are physically inactive.

“Being sedentary increases the risk for heart disease, high blood pressure and dying early,” said lead author Emily Ussery.

She is an epidemiologist at the National Center for Chronic Disease Prevention and Health Promotion, part of the U.S. Centers for Disease Control and Prevention.

Ussery pointed out that sitting may not be bad in itself, but is a proxy for not getting enough exercise.

Study co-author Peter Katzmarzyk added, “In recent years, we have begun to understand the health hazards of excessive sitting.”

Although all the reasons why prolonged sitting is unhealthy aren’t known, Katzmarzyk speculates that “when people sit, they deactivate the large muscles in their legs, and this has a host of metabolic consequences that seem to be harmful.”

Source: Most Americans spend too much time sitting, study finds – CBS News