Asans, commonly referred to as asanas, is probably the most popularised aspect of yoga. There are tons of materials, books, CDs, tapes and what have you on asan(a)s. I have no wish to add much to this literature, so I will be brief.
Based on the above, anybody can be forgiven for thinking that Yog is nothing but asans. However, the relative importance of asans (and even pranayam) in the holistic practice of Yog can be judged by the following paragraph written by Shri S N Goenka, founder of the Vipassana school of Meditation:
"Patanjali has defined asana just by one phrase i.e. the posture in which one can sit for a long time, steadily and with ease. Only this very statement of Patanjali about asana has been elaborated up to 84 types of tiresome postures and all of them are now preached in his name. Poor Patanjali has been reduced to the status of circus trainer and he, who preaches to become aware of the inhalation and exhalation of natural breath, the intermittent stage between the two its elongation and its contraction, has been wrongly associated with the attempted and rigorous breathing exercise of pranayama. Breathing exercise too is not bad. It has got its own advantages but the same should not be ascribed to the name of Patanjali. Likewise different yogic postures too have got very good healthy impact over our body, but the same should also not be said as prescribed by Patanjali in his famous treatise. A sage who bestowed our country with a highly spiritual knowledge of yoga should in no way be allowed to be depicted as a kindergarten P.T. teacher who teaches asana or pranayama"
The full text of the article is available at the URL listed in the Articles section alongside.
Asan basically means seat and that is what it is a seat suitable for mediation. However, one needs to assume this seat for a long time for long meditation periods. So the body has to be made strong and flexible, so the other asans might have developed. I have given links alongside to sites where the asans are listed and explained in great detail with photos.
I am not competent to add much to this information but I will only re-state a few points:
THIS IS EXTREMELY IMPORTANT.
- Do not be in a hurry to do asans. If there is shortage of time, cut down a few asans rather than going through them quickly.
- Do them slowly. Co-ordinate breath with movement. And the awareness should be focussed inside the body, especially the part where the asan is working.
- Try to keep all other parts of the body relaxed especially the face. An asan when properly done should be virtually effortless as the sage Patanjali says "Sthiram Sukham Asanam" "That which is steady and alert, light and comfortable that is an asan"
- There is no need to learn hundreds of asans and certainly no need to practice all of them every day. There are basically six broad categories of asans
- Forward Bends
- Back bends
- Balancing Poses
You ought to learn a few asans in each category (for variety) and then practice at least one or two from each category daily for an allround practice. There is a lot to learn and benefit even from one asana - refer to the article alongside on Sarvangasana, for example..
- Each asan puts a strain on one part of the body or stretches one group of muscles in one direction. It is important, immediately after performing an asan, to do a "counterpose". This is an easier asan that counteracts the effect of the previous asan by relaxing that part of the body that was exercised in the previous asan or stretches it in the opposite direction. For example, a mild back bend (eg dwi-pada-pitham) would be the counterpose for an intense forward bend (paschim-uttan-asan)
- Each asan need be held for a few seconds only or maybe a maximum of a minute or two, there is no need to do it for half an hour to derive the benefits.
- Perfection in an asan is not a compulsory goal. To get benefits it is enough to do it well enough, and not to do it wrongly.
- Further details of all these aspects can be read here.
- The recommended sequence of yog practice is:
The whole practice will take between one to two hours - if short of time, try to incorporate at least Asan, Pranayam and Dhyan.
- It is always preferable to learn asans (or in fact any aspect of yog) under the personal supervision of an expert teacher or guru. If you do not have a teacher, do not worry. Sincerely look for one and more likely than not, he will appear in your life. When the aspirant is serious, the teacher iwill not be found wanting. That is the teaching of the shastras, as well as my personal experience.