"The benefits of exercise before surgery are very clear," said study author Daniel Rooks, assistant professor of medicine at Harvard Medical School, and Beth Israel Deaconess Medical Center in Boston. "The more you can do for yourself physically before surgery, the better off you are."
Rooks added that it was a well-known fact that physically fit people tolerate osteoarthritis better. "Their muscles and soft tissues are stronger and better conditioned, which helps stabilize the knee, protect the joints and allow people with arthritis to move with less discomfort," he said, but the effect of exercise on people with severe arthritis who are facing surgery was less clear.
Rooks and his colleagues studied patients who were about to have surgery for hip- or knee-replacement, and divided them into two groups; an exercise group and a non-exercise group. The exercise group took part in one-hour group exercise sessions three times a week, engaging in water exercises, stationary bikes, machine and dumbbell weightlifting, abdominal strengthening exercises, and stretching.
"It is not unlike a program that you or I would go through," Rooks said.
Of the exercise study group, only 12 of 36 patients had to be discharged to rehabilitation centers after their surgery, compared to 23 of the 43 patients who did not exercise, according to Rooks. Even though the relatively short exercise period of six weeks wasn't enough to boost muscle strength significantly, Rooks noted it ended up benefiting the participants anyway.
"We saw that their level of function stabilized and their pain stabilized prior to surgery," Rooks said. "Those who did not exercise, their function and pain got worse." He added that some of the benefits might have occurred because the participants "were just feeling more confident and comfortable that they could exert themselves without hurting themselves."
According to Rooks, the ultimate finding of the study is that arthritis should not preclude exercising, and it is actually a reason to begin or keep exercising.
A second study, published in the same issue of Arthritis Care & Research, found that weight training aimed at the muscles along the front of the thigh -- the quadriceps -- might help patients with osteoarthritis in their knees.
The study analyzed 221 subjects both with and without knee arthritis -- only 174 participants remained in the study through the entire 30-month period -- and asked them to take part in weight lifting or "range-of-motion" exercises. The researchers found that both groups lost leg strength, but those who lifted weights suffered the loss more slowly. The researchers were unsure as to the exact mechanism for this phenomenon.
Those with arthritis didn't report any reduction in knee pain through exercise, and participants turned in conflicting reports about whether weight training might have a positive effect on the narrowing of space between joints, said lead researcher Alan Mikesky, a professor at Indiana University's department of physical education. The researchers said more studies are needed.
Dorothy Dunlop, research associate professor at Northwestern University's Institute for Healthcare Research, noted that previous studies have suggested exercise can reduce disability in people with arthritis.
"In addition," she said, "Physical activity has broad health benefits: It improves endurance, reduces depression and is linked to reduced premature mortality."
Dunlop noted that, unfortunately, 24 percent of arthritis patients do not take part in moderate-intensity physical activity, according to a 2001 federal survey.
"The Arthritis Foundation and the Centers for Disease Control have designed programs that provide safe and beneficial physical activities for persons with arthritis," she said. "The opportunities are there. The benefits of physical activity are real. The consequences of inactivity are serious. It is time for persons with arthritis to get moving."