By Richard Alleyne, Science Correspondent
Originally published in The Tribune, Summer 2010. Copyright 2010.
Practising yoga really does relax your mind as well as your body more than other types of exercise, a new study claims.
Researchers have found that three sessions of the exercise a week can help fight off depression as it boosts levels of a chemical in the brain which is essential for a sound and relaxed mind.
Scientists found that the levels of the amino acid GABA are much higher in those that carry out yoga than those do the equivalent of a similarly strenuous exercise such as walking.
The chemical, GABA, is essential to the function of brain and central nervous system and which helps promote a state of calm within the body.
Low GABA levels are associated with depression and other widespread anxiety disorders.
Scientists from the Boston University School of Medicine, USA, spent 12 weeks monitoring two groups of healthy individuals, half of whom walked for three hours each week, while the other half spent the same time doing yoga.
Participants brains were scanned before and after the study using magnetic resonance spectroscopic (MRS) imaging to measure GABA levels, while they were also asked questions about their psychological wellbeing throughout the study.
Those who did yoga reported lower levels of anxiety and increases in their mood than the walkers.
Professor Chris Streeter said yoga participants increased feeling of wellbeing was associated with GABA levels.
He said: "Over time, positive changes in these reports were associated with climbing GABA levels."
Prof Streeter called for further research into using yoga as a treatment for other forms of mental illness.
The research was published in the Journal of Alternative and Complementary Medicine.
Katie Prior, of mental health charity Mind, welcomed the study.
She said: "Any kind of exercise is good for improving a person's mood and self esteem. It makes you feel good and look good, both of which help with mental wellbeing.
"Yoga is a relaxing, low impact activity for people who don't like the thought of walking or running.
"It can be done in the privacy of a person's own home, or people can join a class where they can meet others – this is a great way to meet people, especially for those who may suffer from isolation and loneliness."
The research is good news for yoga which along with pilates was criticised earlier this month for not pushing the body as hard as other exercises.
The University of Wisconsin said that it fell short of what was considered an all-round workout.
They found that while yoga did improve strength, endurance, balance and flexibility, they burned very few calories — suggesting they had not pushed their bodies hard enough to gain substantial aerobic improvements.
In fact, researchers found that a typical class used 144 calories in 55 minutes— the same amount burned during a slow walk.
Even power yoga, which requires participants to perform poses in quick succession, was found to burn only about 237 calories per class and to boost the heart rate to only 62 per cent of the maximum that constitutes a light aerobic workout.
A heart rate of 64-94 per cent maximum is the level needed to work the heart and lungs effectively.
On average, a 50-minute Pilates session burned 174 calories (beginner) and 254 (advanced) — half the amount you might burn on a run of similar duration.