A new study has said that people who suffer chronic lower back pain benefit equally from yoga and stretching classes.
The findings, described by authors as the largest US randomized trial on yoga to date, appear in the October 24 issue of the Archives on Internal Medicine, a journal of the American Medical Association.
"We found yoga classes more effective than a self-care book -- but no more effective than stretching classes," said lead study author Karen Sherman, a senior investigator at Group Health Research Institute in Seattle.
"We expected back pain to ease more with yoga than with stretching, so our findings surprised us," she said.
The same group of researchers conducted a smaller trial in 2005 based on a randomized sample of 101 adults. That study suggested yoga was the best remedy for back pain because those who practiced it used fewer pain relievers and had better back function.
The latest data is derived from a sample of 228 people across six cities in the western state of Washington, and while it showed a slight lead by the yoga class, the difference was not enough to matter statistically.
The subjects were assigned to 12 weekly classes that lasted 75 minutes each.
The yoga was a type known as viniyoga, which features poses adapted for the individual condition of those in the class, breathing exercises and a deep relaxation period. Classes were taught by instructors with more than 500 hours of training.