Asanas are postures for Kriya Yoga and are the third limb of Ashtanga Yoga. These postures can be adopted while sitting, lying down, or even standing. Sitting postures are predominantly used during pranayama practice.
Asanas are to be regularly practiced until one attains higher states in yoga. It is a method of conditioning the body and mind. One should choose the asana(s) that permits sitting for long durations. Also, select a comfortable place where there will be minimal interruptions and distractions. It is also most beneficial to have a supply of fresh air.
Your clothing should be loose and comfortable, and preferably made of a natural fiber, such as cotton. For all asanas, your body should not come in direct contact with the floor. You should sit or lie on a soft woolen or cotton mat (any natural fiber). If using a chair, also place a mat under your feet so they do not directly touch the floor.
Asanas transform the nature of one’s entire body. In many people, the nerves become dull and lose sensitivity over time. With the practice of pranayamas, the nerves become sensitized, activated and energized. These changes are instigated mainly through the Sushumna Nadi, a major energy channel which passes through the center of the vertebral column. For this reason, it is necessary to always keep the head, neck and spine straight during asanas. This will distribute the body’s weight evenly between the ribs and pelvis. While sitting in asana, one’s blood circulation changes. For example, in Padmasana (lotus posture), blood circulation to the legs will be reduced and blood flow to the upper body will be increased.