Every additional hour spent sitting doubles the risk of adults over the age of 60 becoming disabled, regardless of one's exercise routine, a new Northwestern Medicine study reports.
The correlation is so strong, the study shows, that if there are two 65-year-old women, one who sits for 12 hours a day and another for 13 hours a day, the latter is 50 percent more likely to be disabled.
The study's lead author explains some ways people can avoid sitting for long periods of time.
"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 their participation in moderate or vigorous activity," Dorothy Dunlop, professor of medicine at Northwestern University Feinberg School of Medicine, said in the press release.
Disability affects more than 56 million Americans, and is defined by limitations in carrying out basic activities, such as eating, dressing or bathing oneself, getting in and out of bed and walking across a room. Disability increases the risk of hospitalization and institutionalization and is a leading source of health care costs, accounting for $1 in $4 spent, the researchers note.
Researchers sampled 2,286 adults aged 60 and older from the National Health and Nutrition Examination Survey, and compared them to participants in similar health who do the same amount of moderate vigorous physical activity. From 2002 to 2005, they were asked to wear accelerometers to measure the time they spent sitting and engaged in physical activity.
The study is not without its limitations, however. Because it only looks at one point in time, the experiment and its results don't irrefutably determine a cause and effect relationship between sedentary behavior and disability.
"It draws attention to the fact that this is a potential problem," said Dunlop, who is doing a longitudinal study on sedentary behavior and disability risk.
