Every extra hour sitting on couch doubles seniors' disability risk, study finds

You may have heard this one before -- sitting too much can be unhealthy.

Recent studies have called out a sedentary lifestyle as a major risk factor for obesity, heart disease, diabetes, cancers and -- not surprisingly, based on those chronic conditions -- premature death.

Now, new research adds disability to the list, and paints a stark portrait of what the future might look like for many older adults. Researchers linked every additional hour a day adults over 60 spend sitting to a doubling of risk of being disabled -- regardless of whether you're getting exercise. The findings are reported in the Feb. 19 issue of the Journal of Physical Activity and Health.

"This is the first time we've shown sedentary behavior was related to increased disability regardless of the amount of moderate exercise," lead researcher Dr. Dorothy Dunlop, a professor of medicine at Northwestern University Feinberg School of Medicine in Chicago, said in a press release. "Being sedentary is not just a synonym for inadequate physical activity."

About 56 million Americans are disabled, meaning they experience limitations performing basic daily activities like getting dressed, eating, walking and bathing.

Dunlop and her team studied nearly 2,300 U.S. adults aged 60 and older who were enrolled in a nationally-representative government health and nutrition survey.

Participants wore accelerometers between 2002 and 2005 to measure how often they sat or engaged in moderate or vigorous physical activity (brisk walking is considered moderate).

More than 60 percent of the participants engaged in sedentary behavior at least 9 hours a day.

The researchers concluded if there were two 70-year-old women and one was sedentary for 12 hours a day and the other sat for an average of 13 hours, the latter would be 50 percent more likely to be disabled.

"Sedentary social activities were especially prevalent among women, a subgroup which may warrant special attention," wrote Dunlop and colleagues.

The researchers report that sitting too much was almost as strong a risk factor for causing disability as not exercising, a finding that admittedly surprised Dunlop.

"It means older adults need to reduce the amount of time they spend sitting, whether in front of the TV or at the computer, regardless" of if they're exercising.

She says strategies to reduce sitting should target the sedentary behaviors that are most commonly reported by older adults: talking on the phone, watching TV, reading and listening to music.

One suggestion the authors had was to offer physical activity during social activities for seniors such as book clubs, quilting groups or bingo. Replacing as little as 30 minutes of sitting time a day with light activity may boost older adults' physical health, they said.

Dunlop says she wears an activity tracker on her wrist that's synched to her smartphone and social network, so friends can track each other's exercise.

"It's great reinforcement to keep moving," Dunlop said.

Here are some apps that may help you keep moving, from CBSNews.com's "Eye on Apps."