Sit less, extend your life, according to a new study.

The study, published Monday in the journal BMJ Open indicates that Americans spend approximately 55 percent of their day – or seven-and-a-half hours – sitting.  However, it appears that if people reduced their time spent seated to less than three hours a day, they may boost their lifespans by an extra two years.

Furthermore, cutting TV viewing time down to less than two hours a day may extend a person’s life by approximately 1.4 years.

The researchers used data from the National Institutes of Health’s National Health and Nutrition Examination Survey (NHANES) from 2005/2006 and 2009/2010, which included nearly 167,000 adults.

“[These results] elevate the prominence of sedentary behavior,” said lead researcher Dr. Peter Katzmarzyk, a professor of population science at the Pennington Biomedical Research Center in Baton Rouge, La., “We showed that sitting is attributable for 27 percent of all deaths in the U.S., while TV viewing is attributable for 19 percent of deaths…The numbers are very similar to obesity and very similar to smoking.”

Previous studies have linked sedentary behavior with a higher risk of obesity, type 2 diabetes and cardiovascular disease, which all contribute to increased mortality rates.

According to Katzmarzyk, simply engaging in moderate exercise once a day isn’t enough to combat the negative health effects of sitting.

“What we can do from a physician standpoint is not only encourage people to be physically active for 30 minutes a day, but also encourage them to sit less,” Katzmarzyk said.   “Our physical activity guidelines say 30 minutes a day – well, what about other 23 and a half hours?

“Even among people who are active, if you sit a lot, you still have that risk,” he added.

Katzmarzyk said the workplace, in particular, is an area where improvements can be made to decrease time spent sitting and improve health.

“Some people have very active professions, like nurses, waitresses and construction workers who are constantly on their feet,” he said.  “On the other hand, there’s a large segment of the population who sit in front of computers.”

Some ideas being tested are the use of treadmill desks or stand-up desks.  Katzmarzyk also recommended walking over to a co-worker’s desk and speaking in person, rather than emailing them, as well as ‘walking meetings.’

“There are a lot of options to break up sedentary behavior during the day,” Katzmarzyk said.