Practising controlled breathing techniques can lower the amount of pain people feel, according to a recent US study.

The study has implications for sufferers of diseases that cause chronic widespread pain, and offers an explanation for why previous studies have found yoga and Zen meditation both reduce painful sensations.

Researcher Arthur Craig of the Barrow Neurological Institute at St Joseph's Hospital in Phoenix, Arizona, said that the finding fitted in with other research about the effects of fibromyalgia upon the moods and pain responses of sufferers.

For the purposes of the study, the researchers recruited two groups of women between the ages of 45 and 65.

Half of the women were fibromyalgia (FM) patients, and half of the women seemed to be healthy.

When the subjects were given painful pulses of heat on their palms, they were asked to try reducing their rate of breathing by 50%.

They were also asked to report the intensity of the pain, their discomfort with it, and how they felt emotionally.

The same trial was also performed using normal rates of breathing.

The healthy study subjects reported experiencing reduced pain.

There was a diminished pain response in the fibromyalgia patients whose emotional state improved with reduced breathing.

Craig said that the patients whose mood improved had positive energy left in their 'mental battery.'

He said that such patients could use their positive mood increase to reduce pain.

A spokeswoman for the Arthritis Research Campaign said that relaxation techniques could be helpful in many conditions.

She said that such relaxation methods worked partly by relaxing tense and painful muscles and partly by relieving anxiety.

Yoga Biomedical Trust director Robin Monroe said that slow breathing was well known as a means of reducing pain, and that when people's blood levels of carbon dioxide took a subtle increase, there was also a reduced reaction in the sympathetic nervous system leading to reduced pain.

She said that, however, proper breathing techniques required a lot of skill, and that people should learn how to breathe properly with a yoga teacher.