Here's even more incentive for older people to limit the amount of time they spend sitting each day.
New research published in the Journal of Physical Activity & Health shows an association between each extra hour of time spent sitting, and an increased risk of disability. Plus, researchers found that this association was independent of moderate vigorous physical activity. (Disability is defined as having limited ability to engage in everyday tasks, such as bathing, eating, dressing and walking from room to room.)
Look at the relative risk for disability associated with sedentary time and other chronic conditions (story continues below infographic): 
The study, led by Dorothy Dunlop, Ph.D., a professor of medicine at Northwestern University Feinberg School of Medicine, is based on data from 2,286 adults ages 60 and older who were part of the National Health and Nutrition Examination Survey. All of the study participants wore accelerometers (they were instructed to wear them from the time they got up in the morning to when they went to bed) to objectively track their sedentary time and moderate vigorous physical activity between 2002 and 2005. Researchers compared people who all had similar health statuses and the same moderate vigorous activity levels. Overall, 3.6 percent of the people in the study had disability. And the study participants spent 8.9 hours, on average, being sedentary each day.
The researchers found that the risk of disability doubled for each additional hour a person spent being sedentary. "So if you take two 65-year-old women, with the same health profile and same amount of exercise, and one woman is sedentary 12 hours, her risk of being in that pool of disabled people is about 6 percent," Dunlop explained to HuffPost. "You take a second woman who is sedentary 13 hours, her risk of being in that disabled pool is 9 percent."
The researchers also looked at how certain chronic illnesses, such as arthritis, cancer and obesity, raised the risk of disability. Arthritis, for instance: If you took two 65-year-olds with the same sedentary time, smoking status and amount of moderate vigorous activity, but one had arthritis and one did not, the one with arthritis would have about a 220 percent increased risk of disability, Dunlop explained.