There is no limit on the duration of practice. It is only limited by the time that you have available. However, beginners should not overstrain their muscles. Increase the duration of the practice as the anal muscles become stronger and you gain more control over them.
Which method to practise?
You can practise whichever method you like best, or whichever is most appropriate for the pose in which you practise. However, method 1 is easier and therefore more suitable for beginners. If you find it reasonably easy to locate the area, you should start to practise method 2.
Many people have weak anal muscles (sphincters). This is closely associated with such widespread ailments as constipation and piles (haemorrhoids). Ashwini mudra helps to stimulate intestinal peristalsis (the wavelike motion that propels the stool through the intestines to the anus for evacuation) and therefore is a great help in alleviating consti-pation and thus improving the general health and well-being of the practitioner.
Piles are characterized by an accumulation of blood in the region of the anus. The practice of ashwini mudra helps to squeeze this stagnant blood away from the anus. This process is intensified if the mudra is combined with sarvangasana3. Ashwini mudra physically draws the blood away from the anus and sarvangasana allows the blood to drain downwards back to the heart. Every sufferer of piles should definitely practise this combination daily.
Those people who suffer from prolapse of the anus or rectum should also do ashwini mudra. By strengthening the associated muscles, these ailments will slowly disappear.
As we have already pointed out, everyone who is seriously intending to practise kriya yoga in the future should definitely perform and master ashwini mudra. In this manner you will develop sensitivity in the anal area and be able to isolate the muscles from other muscular systems in the pelvic region. This is important for eventual mastery of moola bandha.
Combinations with other practices
As we have already recommended, ashwini mudra can and should be integrated with sarvangasana. Either method 1 or 2 can be used.
Ashwini mudra method 2 can also be integrated with nadi shodhana pranayama, so that you hold the anal contraction during retention of breath4. The reader can adopt any other combination that his imagination will permit.