One hundred of Australia's top athletes will be involved in research into the controversial Buteyko breathing treatment for asthma.

Olympic swimmer Matthew Dunn, rower Jaime Fernandez, walker Dion Russell and former ironman Craig Riddington will act as guinea pigs after the Atlanta Olympics. The 18-month study will be conducted by a joint team from the Australian Institute of Sport, Buteyko practitioners and respiratory physicians from a Sydney teaching hospital which has yet to be named.

Former squash champion Carin Clonda, herself a chronic asthmatic, has been the driving force behind the project, which has been two years in the making.

Ms Clonda dedicated herself to the project after a course in Buteyko saved her from a debilitating condition on which medication was having no effect.

At her worst, Ms Clonda was on a complicated cocktail of drugs including daily doses of oral steroids and at one stage had to use a nebuliser, which delivers drugs through a mask, every half-hour.

Ms Clonda's case forms part of a growing amount of anecdotal evidence to support the breathing technique but, without any scientific data, the Buteyko method has been cloaked in controversy.

Originally developed in Russia by Professor Konstantin Buteyko, it is based on the belief that asthmatics over breathe, or hyperventilate. By gasping for air, they lower the levels of carbon dioxide in their blood - needed for the lungs to function effectively - making their asthma worse.

Asthmatics are taught to change their breathing habits and take shallower breaths, to help them overcome attacks and later prevent them. However, there is no scientific proof and experts are baffled over why the method has worked in some people.