We witness today that all over Europe and America there have sprung up schools of hatha yoga. This is to be welcomed for several reasons. Most of the teachers are Westerners who have studied, usually for short periods, under an Indian guru who has come to the West and, in a few cases, under one in India itself. It is worth repeating, in this context, that the principal medical officer of the hospital at Rishikesh (which, situated at the foot of the Himalayas, is the greatest centre for practising yogis in India) informed me that more than three hundred cases had passed through his hands of yogis--or rather, would-be yogis--who had damaged their health or become insane through practising a particular breathing exercise connected usually with hatha yoga but also with elementary raja yoga. I refer to the exercise known as "Holding the Breath." Those who practise this exercise imprudently risk damaging their lungs or bursting blood vessels or irreparably injuring the brain--quite apart from the possibility of going out of their mind at least temporarily. The question therefore arises, why was this exercise incorporated in the yoga system? And why has it attracted so many to it? The answer to the second question is that most of those who have attempted it have done so because they have read or heard that it is a quick way to spiritual achievement or, more frequently, that it leads to the acquisition of occult powers. The answer to the first question is that properly performed by the proper person under competent supervision, the danger is eliminated. Since these conditions are not often present, the perils exist. There is no doubt that in the course of the next ten or twenty years we shall be hearing of several cases of self-injury in the West to these students of the yoga schools which have arisen here, unless they are fortunate enough to have a thoroughly responsible and well-informed teacher.
Even apart from the breathing exercises there are dangers in the postures of hatha yoga. The American vice-consul in Calcutta, for example, told me that for a year and a half he had suffered from a crick in the neck which caused his head to be half turned to the left. This was caused by his attempting to practise one of the hatha yoga contortions, but he was doing it under the tuition of an Indian guru! And when the crick happened, his guru was quite unable to rectify the injury, nor were the doctors he was able to contact at the time.
But to return to the breathing exercise: the holding of the breath is beneficial if one has experienced a visitation of grace and an uplift of consciousness. This retention enables one to prolong the glimpse which results from the visitation or which may come from meditation. Conversely, the holding of the breath leads almost directly to the holding down of the thought movement, which of course is also one of the goals of yoga. But since Nature forces the man to recover his breath after some time, the thoughts begin to move again. No doubt, if the exercise is repeated many times, the control of the thoughts becomes easier. Now, the yoga texts which have come down from ancient times give precise figures for the period of retention. With the in-held breath, it should be four times the period taken to breathe in. With the emptied lungs, it should be only twice that period.
Ah! First, people vary in their capacities, and exercises must be adjusted accordingly. For instance, the mountain-dwelling Gurkas of Nepal have broad shoulders and wide lungs and can take in much more air than the half-stooped office worker of a western city. Secondly, the yoga textbooks which were written in the days before printing were intended to be expounded by a competent guru. Hence, they were highly condensed and the present-day reader must pick his way through them very circumspectly if he is working alone.
Now, to return to this holding of the breath. It was not intended to be played with. The eager enthusiast of today plunges into the work quite drastically. He tries to perform the full exercise as he reads it in the translated text. He tries to perform it immediately, and this is where the terrible risk comes in. No beginner should attempt the full exercise of any of the hatha yoga breathings or postures. They should be spread out over a period of three months where the increase is measured in seconds each day so that the full exercise is only reached after daily work--very, very slowly increasing the development. The full exercise is only reached after ninety or one hundred days. This is a necessary precaution.
-- Perspectives > Chapter 5: The Body > # 24