(Associated Press) -- Tai chi eased painful joints and other symptoms of fibromyalgia in a small but well-done study of this ancient Chinese form of exercise.

Tai chi (ty-CHEE') combines meditation with slow, gentle movements, deep breathing and relaxation. It can improve muscle strength, balance, sleep, coordination and, some evidence suggests, fibromyalgia.

Symptoms of the illness include fatigue, body pain, and tender points in joints, muscles and other soft tissues. It is most common in middle-aged women. Its cause is unknown, and the lack of obvious signs or definitive tests has led some doctors to question whether it is a physical or psychological problem.

The study led by Dr. Chenchen Wang at Tufts University School of Medicine in Boston involved 66 fibromyalgia patients assigned to try either tai chi or wellness education and stretching exercises twice a week for 12 weeks.

Symptoms improved significantly for the tai chi group and little for the others, as measured by a commonly used questionnaire. Improvements were seen in pain, mood, quality of life, sleep and exercise capacity, and remained at 24 weeks after the study's start.

The results are in Thursday's New England Journal of Medicine.

In an editorial, two doctors and an Oriental medicine specialist from Beth Israel Deaconess Medical Center in Boston called the results "provocative" and "striking," but said that it's unclear how much of the benefit is due to a placebo effect. The results need to be repeated in a larger study, they conclude.

The study's main sponsor was the government's National Center for Complementary and Alternative Medicine. Several authors have received federal grants for mind-body research and one has financial ties to companies that make drugs to treat fibromyalgia.

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