The Asanas can be mastered progressively through following four levels.
- Asana / Position which involves stability, the body is maintained in a particular Asana for a longer duration while achieving the stability of the all the muscles, whether stretched or relaxed. The effort in this is to stabilize the body and its processes. This is the first level in Asanas as per the classical definition.
- Once the stability is achieved for a certain period of time in any asana, the next level is to feel the comfort in this position. One should be able to maintain the asana comfortably and feel the ease.
- After steadiness and comfort, one should try to progressively relax the muscles, with the practice of relaxation, one can experience greater stability and comfort in the position. Once the body is relaxed, the mind also becomes calm and relaxed, which can be introverted or easily focused.
- And finally this mind can be easily focused on an object of meditation and higher stages of experience can be realized, this level of asana is related to higher mind, the physical experience is transcended.
If one practices Asana with these four levels in progression then one is said to have mastered the Asana, which results in perfection on physical and mental aspects. Ideally if one can maintain an Asana for three hours without discomfort, it is mastery on the physical level, if one can focus the mind on one object during this practice then it is mastery on the mental level.
The natural condition of the body and mind is a relaxed state. By regular practice of Asana, this relaxed condition is achieved without efforts. So if you are just sitting in the office chair, try and make your body relaxed and let the mind become calm & peaceful. Then there will not be any stress or strain on a physical level and no thoughts in the mind. Now we can easily understand what an asana is.
The similar description of Asana is found in Hatha Yoga Pradipika which says that “One can achieve sound health, stability, lightness of body and mind with Asana”.
In Gherand Samhita (Another text on Hatha Yoga), the author describes the effect of asana as “The result of Asana is perfecting the stability of body and mind.”
We can see the other effects of asana in day to day life such as increased efficiency, stamina, increased immune capacity, quiet and calm mind, easy control over emotions and improvement in attitude.