Their study showed patients who followed an eight-class programme of exercise experienced significant benefits compared to those who underwent standard treatment.

Many people who suffer back pain fear activity will lead to greater damage.

But the researchers say the exercise programme's success was so great it should be more widely available.

The Chartered Society of Physiotherapy (CSP) has responded to the findings by calling on the government to adopt back pain as one of its key areas for improving public health.

Such programmes have been shown to be beneficial to hospital inpatients before, but the researchers, based at Hull University's Institute of Rehabilitation, wanted to see if it was effective in a community setting.

Guinea pigs

They looked at 187 18- to 60-year-olds living in the York area who had suffered lower back problems for between four weeks and six months.

A year on from the therapy, patients who had attended the exercise classes suffered less pain and were better able to control the condition than those who had not.

The classes consisted of:

• A gentle warm up involving stretching and low impact aerobics
• Strengthening exercises for all the muscles in the body
• Relaxation exercises
• An educational "tip for the day", such as advising people not to worry if they feel some pain when they try a new activity, as this is not unusual - the trick is to start easy and build up slowly

She told BBC News Online: "The programme allows participants to build up confidence.

"None of the exercises focus on the back, but they all use it."

'Should be key health target'

The CSP responded to the report, published in the British Medical Journal, by calling on the government to make back pain a fifth key public health target.

At the moment, the government's priority areas, set out in the Our Healthier Nation White Paper, cancer, heart disease, accidents and suicides.

But the CSP's chief executive Phil Gray said back pain accounts for 11 million missed working days each year and merits greater attention.

He says: "This research demonstrates the effectiveness of this low cost approach to tackling the back pain epidemic."

Dr Klaber-Moffett agreed the government was missing an obvious public health target.

"It's a great pity the Healthier Nation targets didn't focus more on quality of life," she said.

'What about quality of life?'

"It's fine lengthening people's lives but what about the quality? Rehabilitation and helping people to improve their function and generally be more active and lead a more fulfilling life should be a much higher priority."

She said an important part of that was getting people to get back to work, as back pain accounted for millions of lost working days each year.

Health professionals may sometimes be overcautious in telling people to take it easy, fearing they may eat up doing more damage, she said.