Chanting “om” might help ease your aching back, but only if it comes at the end of yoga practice. A new study finds that the physical act of doing yoga — but not its meditative aspect — may help reduce symptoms of chronic back pain.
Based on smaller previous studies, researchers thought it was some combination of yoga’s stretching and mental elements — deep breathing and relaxation — that improved back sufferers’ function. But the current study found that yoga worked no better than intensive stretching alone, suggesting that it’s the physical exercise, not the mindfulness component, that matters.
Whether doing yoga or stretching, however, it takes effort: participants in the study attended weekly 75-minute yoga or stretching classes for 12 weeks, and did additional 20-minute at-home practices with the help of instructional CDs or DVDs at least three days a week.
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The trial, published on Monday in the Archives of Internal Medicine, is the largest to date on yoga and chronic back pain, a condition that affects millions of adults and often doesn’t have an easy solution. People spend billions of dollars a year seeking relief from pills, doctors, physical therapists and chiropractors. Although there’s no shortage of available treatments for low back pain, including exercise, it’s not entirely clear how they stack up against one another in terms of effectiveness.
For the new study, researchers recruited 228 adults in the Seattle area, all of whom had moderate chronic back pain but were fairly active despite their conditions. The participants were randomly assigned to do either yoga or intensive stretching or, as the control group, to use “self care.”
The yoga group did viniyoga, a style of hatha yoga that focuses on postures that stretch and strengthen back and leg muscles, and include breathing exercises and guided deep relaxation. The intensive stretching class was similarly devoted to exercises that stretch and strengthen trunk and leg muscles, except without the guided breathing and relaxation. And finally, the self-care group was given a book to read, The Back Pain Helpbook, which offers advice on exercise and lifestyle changes for back pain.
Over time, all study participants saw improvements in function, but those doing yoga and stretching did significantly better than the self-care group. By the end of their three-month classes, more than half of those in each exercise group reported at least 50% improvement in measures of day-to-day disability, compared with less than a quarter of the controls.
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At each follow-up interview — conducted at 6, 12 and 26 weeks after the start of the interventions — yoga and stretch class participants were also significantly more likely to rate their back pain as better, much better or completely gone, compared with the self-care group. “More participants in the yoga and stretching groups were very satisfied with their overall care for back pain,” the authors wrote.
Yoga and stretching also helped people get off their pain medications. After 12 weeks, twice as many people in the yoga and stretching classes (40%) reported decreasing their medication use, compared with the self-care group (20%). That benefit lasted for another 3½ months after the classes ended.
Neither yoga nor stretching was more effective than the other, however. “We expected back pain to ease more with yoga than with stretching, so our findings surprised us,” said Karen Sherman, lead author of the study and a senior investigator at the Group Health Research Institute in Seattle, in a statement.
The findings may be attributed in part to the fact that the exercise classes ended up being so similar to each other. The stretching classes were more intensive than most such classes, with participants holding each stretch for a relatively long time. “People may have actually begun to relax more in the stretching classes than they would in a typical exercise class,” Sherman said. “In retrospect, we realized that these stretching classes were a bit more like yoga than a more typical exercise program would be.”
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In an accompanying commentary, Dr. Timothy Carey of the University of North Carolina said doctors should feel comfortable prescribing either yoga or stretching for patients with back pain. “Are the results from this trial actionable for practice?” he wrote. “Yes.”
But Sherman cautioned that not any yoga or stretching class will do. The classes in the study were designed specifically for people with back problems and with no previous yoga or stretching experience. “It’s important for the classes to be therapeutically oriented, geared for beginners and taught by instructors who can modify postures for participants’ individual physical limitations,” she said.
Sora Song is the editor of TIME Healthland. Find her on Twitter at @sora_song. You can also continue the discussion on TIME Healthland’s Facebook page and on Twitter at @TIMEHealthland.