By Genevra Pittman NEW YORK (Reuters Health) - Weekly yoga classes eased pain and improved functioning in a study of patients with chronic lower back pain; but the yoga sessions weren't any better than regular stretching classes. Participants in both types of classes had better functioning and fewer symptoms after three months than patients in a control group. "We've known for a while that exercise is good for back pain," said Dr. Timothy Carey, from the University of North Carolina, Chapel Hill, who wrote a commentary published with the study. Yoga, he told Reuters Health, "seems to be a perfectly good option for people with back pain, but it is not a preferred option." Finding that yoga and stretching had about equal effects means it was probably the stretching involved in yoga, and not the relaxation or breathing components of the practice, that helped improve functioning and pain symptoms, researchers said today in Archives of Internal Medicine. The stud...