Does running increase the risk of knee injury or osteoarthritis?
No. Contrary to widespread belief, running vigorously well into your later years does not raise the risk of knee osteoarthritis (swelling of the joint, with pain and stiffness, caused by wear and tear) or other disabilities. To the contrary, it can improve overall health, cutting the death rate in half, according to two new studies by Dr. James Fries, a professor of medicine at Stanford University. Both studies bolster previous research on exercise, disability, and longevity.
"The persistent myth about exercise - and running, in particular - is that it increases joint problems, arthritis, and will ultimately destroy joints and lead to disability," said William J. Evans, an exercise physiologist and chair of nutritional longevity at the University of Arkansas for Medical Sciences. Not only is this "not true," he said, but the opposite is true: "There is decreased disability after decades of running."
Both Fries and Evans noted that while the two new papers focus on running, they believe the results apply to all aerobic exercise. "This study has a very pro-exercise message," said Fries, a mountaineer and longtime runner. "If you had to pick one thing to make people healthier as they age, it would be aerobic exercise."
In one of his new studies, published in the Archives of Internal Medicine, Fries gave annual questionnaires to 538 runners and 423 healthy men and women. All were at least 50 years old when the study began in 1984. After 21 years of follow up, only 15 percent of the runners had died, compared to 34 percent of the non-runners, a greater than two-fold difference.
Just as important, Fries said, the runners were less likely to be disabled. They were able to delay disability - defined as anything that can make it more difficult to perform normal daily tasks - by 16 years.
In the other study, published in the American Journal of Preventive Medicine, Fries focused on 45 runners and 53 non-runners, all aged 50 or more in 1984, and gave them periodic knee X-rays to detect possible osteoarthritis. After 18 years of testing, there was no increase in risk among runners, he said.
Bottom line? Get up and exercise, at least half an hour a day, at least five days a week, Fries said. And go at a speed that causes you to break and maintain a sweat, but not so fast that you can't talk to an exercise partner.
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