Another of Dr Buteyko's unique contributions is the use of restrained under breathing to the point of experiencing a sensation of light lack of air for prolonged periods of time. The Buteyko method also utilises systemic breath holding. The rationale given is that it allows the rapid accumulation of CO 2 levels. This allows homeostatic mechanisms that have adapted to habitual low levels of CO 2 due to chronic hyperventilation to normalise. The possibility exists that the success of underbreathing and breathholding in modifying many disease processes also has to do with the fact that the body is being trained to tolerate hypoxia, making it ultimately able to better utilise oxygen.
Athletes know that training at altitude can enhance performance at sea levels.
I personally remember feeling better than I have ever felt after returning to low altitude after adaptation to high altitude in the Himalayas. The use of intermittent hypoxic breathing training was developed by other Russian doctors such Professor Assya Kolchinskaja and Professor R.S. Vinitskaja of the Commission for Advanced Medical Technologies of the Ministry of Health Care of the Russian Federation. Cancer patients using this treatment were found to have an increased resistance to radiation treatment. A device called a hypoxicator delivers low oxygen metered pressure. Overall treatment sessions last for about hour daily.