WASHINGTON (AP) _ Exercise can help older people avert a form of arthritis that can turn ordinary activities such as getting out of bed into a painful _ perhaps impossible _ chore, a study finds.
Those who regularly walked or did weight training were less likely to lose abilities to perform activities of daily living, such as getting out of bed, the study says.
The report is the first to demonstrate that exercise can help people avoid relying on others for help in these ordinary activities, said researcher Brenda Penninx of the Wake Forest University School of Medicine.
Penninx and her colleagues looked at 250 participants ages 60 and older. When the study started, all could perform normal activities, despite osteoarthritis of the knee. Osteoarthritis is characterized by progressive deterioration of cartilage, and affects more than 80 percent of those who reach the age of 70.
The participants were divided into three groups. One walked for 40 minutes three times a week. Another spent the same amount of time on weight training _ two sets of 12 repetitions of nine exercises, most of them for the legs. The third did no exercise and served as a comparison group.
Results of the study were published in the Oct. 22 issue of Archives of Internal Medicine.
After 18 months, 53 percent of the non-exercise group reported they had lost some or all ability to transfer from a bed to a chair, bathe, use the toilet or dress. In comparison, about 37 percent of exercisers did, and the difference between walking and weight training was so slight that researchers considered the benefits alike.
``I definitely think that people with knee osteoarthritis would benefit from a resistance or aerobic program,'' Penninx said. ``What this study shows is that exercise is beneficial.''
And the anti-disability benefits may extend beyond the knee, because 75 percent of the study participants had arthritis elsewhere, Penninx said.
Previous studies have found that exercise reduces pain and improves muscle tone, balance and the ability to do things such as walk, but this is the first to go to the next level and examine prevention of disability, Penninx said.
The study gives a stronger foundation to current medical support for exercise.
``I can't think of anybody I wouldn't put on an individual exercise program,'' said Dr. Roland Moscowitz, a medical professor at Case Western University. Walking on a treadmill almost always helps, and weight training can help too, provided the person in charge of training knows how to avoid damaging a patient's joints, he said.
Exercise probably is best for people in early stages, before development of joint deformity, extensive cartilage loss and continuing pain, said Dr. Marian Minor of the University of Missouri.
``I'm trying to make a case for prescription of exercise early _ not thinking you are going to rescue people later,'' said Minor, a researcher who was not connected with the Wake Forest study.
In addition, keeping people active will reduce the chance that a sedentary lifestyle will lead them to develop heart disease in addition to the arthritis, Minor said.