Yoga is effective at relieving chronic lower back pain, although no more effective than traditional stretching exercises, a new study — the largest and best designed on this topic to date — has found.

This is good news for the substantial (and growing) number of Americans who develop chronic lower back pain (defined as pain that lasts more than three months with symptoms severe enough to interfere with some daily activities).

The study’s findings suggest that back-pain sufferers now have two non-invasive, non-drug and relatively inexpensive treatment options for relieving their lower back pain.

Surprising results
The study, which was published online this week in the Archives of Internal Medicine, is a comparative effectiveness study, which means it compared treatments with each other rather than with no treatment (placebo). Such studies, which haven’t been done much in the past, are believed to offer physicians and patients better information about which treatments are more effective.

The authors of this study actually hypothesized before the study began that yoga would be superior to stretching exercises and to a third “self-care” treatment, reading a self-help book on pain, which was also investigated. The study’s findings — that yoga and stretching were equally effective — therefore surprised them.

Details, details
The study involved 228 adults with moderate and chronic (but non-sciatica) low back pain. They were randomly assigned to one of three groups. One group (92 patients) was offered 12 weekly yoga classes while another group (91 patients) was offered the same number of conventional stretching classes. Both of these groups were also told to practice 20 minutes a day on non-class days. The third group (45 patients) was given “The Back Pain Helpbook,” which offers information on the causes of back pain as well as exercise and lifestyle modification tips for managing the pain. Participants were followed for 26 weeks.

“Back-related dysfunction declined over time in all groups,” the study’s authors note, although the stretching group reported superior function at weeks 6, 12 and 26 and the yoga group at weeks 12 and 26 when compared with the handbook group.

Participants in the yoga and stretching groups were also less likely to be taking pain medication for their back pain at weeks 6 and 12. Medication use among the self-care group participants didn’t decrease until week 26.

Because the results were statistically the same for the yoga and stretching groups, the authors of the study conclude that the benefits of yoga for relieving lower back pain can be attributed to its emphasis on stretching and not to any of its mental components, such as deep breathing and relaxation meditation.

Caveats
This study, like all studies, has its limitations. For example, participants were recruited from a single geographic area (western Washington state), and most were relatively well educated and physically functional. It’s not clear, therefore, if other population groups would have similar results. Also, participants who were randomized to the self-care book may have been disappointed that they didn’t “get into” the yoga and stretching classes and, thus, may have been more likely to report negative outcomes.

Still, the findings suggest, as the authors of the study note, that “yoga and stretching are reasonable treatment options for persons who are willing to engage in physical activities to relieve moderately impairing back pain.” And the benefits last for at least several months.

Of course, such classes vary widely in approach and quality. So be sure, the study’s authors add, that the class you sign up for is therapeutically oriented, aimed at beginners and taught by instructors who are comfortable modifying positions for individuals with physical limitations.