A traditional Chinese martial art can help reduce pain and improve knee function among seniors with osteoarthritis, American researchers have found.

"Tai chi is a mind-body approach that appears to be an applicable treatment for older adults with knee osteoarthritis," Dr. Chenchen Wang, co-author of a study published in the November issue of Arthritis Care & Research, said in a release.

Tai chi features slow, rhythmic movements designed to relax people and enhance balance, strength and flexibility.

In the study, researchers looked at 40 people with confirmed knee osteoarthritis from Boston who were in otherwise good health. They had an average age of 65.

Half the study participants took Yang-style tai chi sessions for one hour, twice a week for three months. The sessions included 10 minutes each of self-massage and review of principles, breathing techniques and relaxation, and 30 minutes of tai chi movements.

The rest took two 60-minute classes per week for three months to learn about diet and nutrition, and treatments for osteoarthritis. These participants also stretched for 20 minutes.

At the end of the 12-week period, people practising tai chi showed a significant decrease in knee pain on a standard pain scale compared with those in the control group.

The findings show the need to further evaluate the biological mechanisms of tai chi to extend its benefits to a wider population, Wang said.

No severe adverse events were reported.

Osteoarthritis affects an estimated 3,000,000 or one in 10 Canadians, according to the Arthritis Society.