We know that regularly getting some exercise, no matter how little, can keep you alive longer. But new research out Monday suggests that even an hour’s worth of walking per week can help older adults with ailing knees avoid painful, isolating disabilities down the road.
The researchers looked at data from an earlier project studying thousands of middle-aged and elderly Americans with knee osteoarthritis, the Osteoarthritis Initiative, which began in 2004. At the beginning of the project, the volunteers got a full medical check-up and answered questions about their lifestyle habits, then had their health periodically followed for up to 8 years.
For the current study, the researchers looked at around 1,500 adults who had knee pain but no other disability at the beginning, then tracked them over a four-year period.
By the end of those four years, they found that only 3 percent of people who reported getting an hour of moderate to vigorous exercise (the equivalent of at least a brisk walk that leaves you breathing a little heavy) became so disabled that they could no longer safely cross the street on their own, while 24 percent of people who didn’t meet that exercise threshold were disabled by the end of the study period—an eightfold difference in risk. The exercisers were also half as likely to have trouble with daily activities like putting on clothes or taking a shower on their own (12 percent vs 23 percent).
The findings were published Monday in the American Journal of Preventive Medicine.
Exercise is already known to help prevent conditions like knee osteoarthritis, the most common form of arthritis in the knee. And it can also improve symptoms, reduce pain, and slow down the disease’s progression in people who already have the degenerative joint disease. But Dunlop and her team were motivated to find the least amount of exercise it took to feel these effects, since many older people with knee pain find it hard enough to move.
“Much evidence shows physical activity is beneficial for people with arthritis. What this study additionally demonstrates is as little as one hour of brief walking each week is beneficial to help people maintain abilities which are central to being independent,” lead author Dorothy Dunlop, professor of preventive medicine at Northwestern University Feinberg School of Medicine, told Gizmodo.
Currently, it’s estimated that more than 30 million Americans have knee osteoarthritis in at least one leg—a number that will only rise with an aging population. And agencies like the Centers for Disease Control and Prevention recommend that adults with osteoarthritis try to get around two-and-a-half hours worth of moderate exercise a week at least. The team say their findings should put people daunted by that recommendation more at ease.
“This is encouraging news because one hour may be a feasible goal for many people with stiff or aching joints for whom the standard two-and-a-half hours of activity per week difficult,” said Dunlop.
One possible caveat of the study, though, is that the people capable of exercising in the first place might have already been healthier in general than those who subsequently didn’t exercise much. But other research has consistently linked exercise to benefits in preventing or managing knee osteoarthritis. As always, the takeaway message is to get moving, as much and as often as you can—even if it’s just for a stroll around the block.