Sit on the ground with the left leg bent so that the heel touches the anus. The right leg also should be bent so that the right heel touches the left buttock. Care should be taken that the left foot remains straight touching the ground and the toes of the right foot also touch the ground. The right arm should be raised and bent at the elbow behind the shoulders towards the back. The left arm should be bent upwards behind the back so that all the fingers of both the hands are interlocked. Then the right elbow should be lowered as far as possible. During all this, the eyes have to be kept open and the respiration has to go on as usual. The process should be repeated by starting this time on the right side instead of the left as described above.
The practice of this asana gives strength to the feet, knees and waist.The arms and shoulders develop.The chief and unique characteristic of this asana is that it is helpful in disease of the lungs.Patients of asthma and phthisis (tuberculosis of the lungs) should specially practice it because the respiratory movement of the lung on the side on which it is performed is almost stopped and the other lung works more rapidly and vigorously.By alternating its practice, the resting lung can be forced into a state of increased activity.This way the cleansing as well as the haemo-circulatory actions on the lungs are initiated and enhanced.It is possible to inhale markedly greater amounts of oxygen than is ordinarily needed.In this manner, innumerable pores and alveoli of the lungs get cleaned up.It is on this account that yogis have held the practice of this asana to be of a general utility for all types of individuals.