In this blog for our Evidence for Everyday Health Choices series, Jack Leahy, Cochrane UK’s Communications and Engagement Officer, writes about his own experience of practising yoga and the latest Cochrane evidence on yoga for people with chronic non-specific low back pain.
“Keep twisting! Wring out all those toxins!”
“Now lie back and feel the stale blood drain out of your legs.”
“Relax and feel small to moderate improvements in back-related function at three and six months.”
Two of those quotations are biologically impossible instructions I have received in yoga classes; the other is based on a recent Cochrane review. Whilst I feel there is often too much ‘woo’ around yoga practice, I enjoy the classes and there is a growing evidence base for the benefits of yoga. It won’t wring toxins from your body (your liver and kidneys will do that), but let’s take a look at some of the evidence on yoga for chronic non-specific low back pain (or general back ache to most people).
What does the evidence say?
Low back pain
A recent Cochrane review concluded that yoga may improve back pain at three to four months compared to no exercise. However, the pain improvement was not enough to be meaningful to patients.
The review authors also found that yoga probably increases the risk of increased back pain compared to no exercise. To me, this is common sense, when you undertake any form of exercise, you increase your risk of injury!
They found it was unclear whether yoga was beneficial compared to other forms of exercise or whether adding yoga to another type of exercise was more effective than another type of exercise on its own.
The review authors also looked at whether yoga was beneficial for back function. That is to say, how yoga improved the activity-limiting aspects of low back pain. People taking part in the studies were asked to complete the Roland-Morris Disability Questionnaire to assess this. Did yoga help patients walk faster? Did it improve sleep quality? Did it help people putting on their socks in the morning? This last question really highlights how debilitating low back pain can be. Getting dressed in the morning can become a long struggle.
They found that yoga compared to no exercise may improve back function for up to a year. The review authors found that for back function, as with back pain, it was unclear whether yoga was beneficial compared to other forms of exercise or whether adding yoga to another type of exercise was more effective than another type of exercise on its own.
How reliable is the evidence?
The reason for the uncertainty in the results on back pain and function (all those mays and unclears) is that the studies the review authors looked at were poorly designed. Most of the studies were not blinded. That is to say both the participants (yogis) and the practitioners (yoga teachers) were aware who was practising yoga and who was not. This is pretty obvious, I think anyone who has been mid way through Camel pose (Ustrasana) is fully aware they are doing it. This leaves room for an unconscious bias when the participants report on their back pain and function.
The review authors call for more, better-designed trials comparing yoga to no exercise to improve the reliability of the effects of yoga. They also call for trials that investigate other important outcomes such as depression and quality of life.
What is my experience?
I’ve not been diagnosed with chronic low back pain, but after sitting at a desk all day, my shoulders and back feel stiff and are sometimes painful. After a yoga class, I feel better. What I take from the Cochrane review is that exercise may be good for chronic low back pain. Yoga is a form of exercise and may improve your back pain. But it is not clear that yoga is better than other forms of exercise.
I practise yoga because it is the only form of exercise that I have stuck with for any length of time. I have 3 pairs of swimming goggles and a pair of squash shoes that are longing to be taken out of the cupboard and fulfil their potential. Yet it is my yoga mat that reaches sweat-soaked Nirvana every week. Namaste.
Yoga treatment for chronic non-specific low back pain. Cochrane Database of Systematic Reviews 2017, Issue 1. Art. No.: CD010671. DOI: 10.1002/14651858.CD010671.pub2., , , , , .