There are conflicting opinions expressed regarding the most suitable duration of sarvangasana. But actually there should be no contradiction, for the duration depends on many factors. Beginners should practise sarvangasana for no more than a minute for at least two or three weeks of daily practice. Then this duration can be increased by thirty seconds every week. If you like you can increase by a few seconds every day – this is your choice.
For general health benefits, and for a person with reasonable purity of body, we recommend no more than three to five minutes in the final pose. If you want to increase the duration then we suggest you seek the guidance of a suitable yoga teacher who can assess your physical suitability. Often a person is recommended to practise prolonged periods of sarvangasana to remove specific illnesses. Under these circumstances, again you should seek expert guidance. If you practise sarvang-asana for too long and your body is not prepared or is full of impurities, then the asana may cause harmful results. Sarvangasana and other inverted asanas can give wonderful benefits if, and only if, they are done correctly and for a suitable duration for the particular individual. It is when people practise them for excessive lengths of time that they cause themselves harm.
The best rule is to follow the dictates of your body. If you feel tired or any form of discomfort, then this is a sure indication that you have stayed in the final pose for too long. In this case immediately terminate the asana. But this is the upper limit; long before this point of tiredness you should have finished the asana.
You may wish to practise sarvangasana for a prolonged duration in order to increase brain power, or as a meditational technique, or as a preliminary to other meditational tech-niques. There is no harm in this” providing your body is healthy, the blood reasonably purified and providing you have been regularly practising other asanas for a year or so. There is no reason why you should not practise for fifteen or thirty minutes. But again we advise you to seek expert guidance.
It is essential that you practise a counterpose after any inverted asana. In the case of sarvangasana, the counterpose can be any asana which bends the head backwards in the opposite manner to that which it takes during sarvangasana. The best asanas are bhujangasana3, ushtrasana4 as well as various other asanas such as chakrasana5, supta vajrasana and matsyasana6. These should be performed for at least a minute or so in order to remove the tension in the neck.