The potential for yoga to be used to treat low back pain is being investigated by researchers.
Some research suggests yoga can help
Millions of UK people suffer from chronic low back pain, and existing treatments have only a limited effect.
A team of academics, yoga teachers and practitioners have joined forces to find out if a 12-week course of yoga can make a difference.
The Arthritis Research Campaign-backed project will assess moves from the two most popular types of yoga.
These are lyengar yoga and hatha yoga, favoured by the British Wheel of Yoga.
More than 260 people between the ages of 18 and 65 who have had back pain in the past 18 months will be recruited for the trial.
Recent, small studies in the US have shown that yoga can be helpful for back pain sufferers.
But David Torgerson, director of the University of York Clinical trials Unit, and Jennifer Klaber Moffett, deputy director of the Institute of Rehabilitation at the University of Hull, believe a bigger study is needed to unequivocally establish the benefits.
Professor Torgerson said: "Yoga offers a combination of physical exercise with mental focus that may make it a suitable therapy for the treatment of low back pain.
"If the trial shows yoga to be effective then this low-cost treatment will have a considerable impact in the quality of life of patients with back pain."
Yoga develops flexibility and muscular endurance by allowing the muscles to be stretched and strengthened.
Patients will be recruited from GP surgeries from September and the 12-week classes, to be held in north and central London, York, Manchester and Cornwall, will begin in November.
The classes will be run by 10 experienced yoga teachers who have all received specialist training.
No difficult poses
Half the participants will take part in yoga classes, and the other half will receive the usual care.
They will be assessed at the end of the classes, then six months and a year later to see if there are any longer-term benefits.
The yoga classes will be carefully structured for people who are complete novices and will not involve any difficult poses.
They will be graduated over the 12-week period, starting off gently and becoming more demanding, with a combination of stretches, bends, lying sitting, standing and relaxing poses.
Patients will also be encouraged to practise daily at home.
Anna Semlyen, a yoga teacher who is helping to run the classes, said: "Regular yoga increases the benefits, and we would hope that at the end of the 12 weeks people would carry on."