"There's kind of a myth that says if you have arthritis, the good thing to do is to rest your joints," says a John Hopkins professor who co-authored a study that might bust the myth wide open.

In the study of 75 sedentary adults with rheumatoid arthritis or knee osteoarthritis published in the Journal of Rheumatology, researchers found that subjects who practiced an hour of yoga three times a week for eight weeks enjoyed higher energy, less depression, reduced pain, and improved flexibility and walking ability, reports Time.

Researchers pegged the improvement at 20 percent over those in the non-yoga control group and say the benefits were still evident nine months later. Lead author Susan Bartlett tells Medical Daily that one subject even went on to become a marathon runner.

More than 95 percent of the study's subjects were female, but Bartlett tells the website that for the purposes of this study, it made sense: 70 percent of rheumatoid arthritis sufferers are women.

One caveat, one of the researchers tells Time: Not all yoga classes are equal and could even harm arthritis patients, so he advises checking with one's doctor and seeking out the gentler regimens found in classes for older, disabled, or pregnant students before heading straight into Downward-Facing Dog.

This article originally appeared on Newser: Yoga 3 Times a Week Pays Big Dividends

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