Most health professionals recommend physical activity to soothe the symptoms of rheumatoid arthritis (RA).  However, a recent study found that two in five adults (42 percent) who have RA are inactive.

The study, funded by a grant from the National Institute for Arthritis and Musculoskeletal and Skin Diseases (NIAMS), highlighted a need for public health measures to motivate people with this autoimmune disease to up their physical activity, the researchers say.

"While there is much evidence of the benefits of physical activity, RA patients are generally not physically active, and physicians often do not encourage regular physical activity in this patient population," said Dr. Jungwha Lee, an assistant professor in the Department of Preventive Medicine at Northwestern University Feinberg School of Medicine in Chicago, Illinois. "Our study aims to expand understanding of the risk factors associated with inactivity among adults with RA and encourage clinical interventions that promote participation in physical activity."

According to the Arthritis Foundation, RA affects about 1.3 million Americans, and there is no cure. It involves the immune system attacking the thin membrane that lines the joints, causing irreversible damage. However, there are highly effective treatments. Engaging in moderate physical activity on a regular basis is recommended because it decreases fatigue, strengthens muscles and bones, and increases flexibility and stamina. Exercise also helps patients attain an improved sense of well-being, the Foundation reports.

In the study, researchers found that while 42 percent of the RA patients studied were inactive, 53 percent lacked strong motivation for exercise, and 49 percent did not strongly believe that physical activity had benefits to their condition. These risk factors - which account for 65 percent of the participants' inactivity - are modifiable, the researchers said.

"Physical inactivity among RA patients is a public health concern," Dr. Lee concluded in the study. "Our results suggest that public health initiatives need to address the lack of motivation to exercise and promote the benefits of physical activity to reduce the prevalence of inactivity in those with RA."

Exercise can also improve symptoms for people who have osteoarthritis, which usually affects older adults because it is caused by aging and the "wear and tear" on joints, the Foundation reports. Joint replacement surgeries and medications can help, but physical activity can improve the condition in the same ways it helps those with RA - strengthening bones and muscles and improving overall well-being.