Turning our body upside down
Inversions are potent asanas! Shoulderstand and headstand are known as the Queen and King of yoga poses, their profound nature is due to the dramatic effect on both our physiological and psychological bodies. Physiologically inverted asanas affect blood flow, endocrine function, muscle tone, waste removal, organ function, and breathing patterns. Psychologically inversions turn our world upside down, giving us a new perspective in life. When we get comfortable being upside down, it is not such a drama when our lives get overturned, we are better able to function and move forward in any situation. Inversions also increase mental power and concentration, improve health, reduce anxiety and stress, and increase self-confidence.
Inverted asanas are first and foremost about blood flow! Stale blood and lymph stagnates on the lower areas of our organs, unless we get our heart rate up to a high rate, blood circulates only through the upper areas of our organs, leaving stale blood to accumulate in the lower regions of the organs. In this stale blood is where disease begins. When we invert this stale blood and lymph is drained from the organs, put back into the circulatory system where the blood is cleaned out oxygenated taking fresh nutrients and oxygen to the cells in our organs. In yoga philosophy this is why they say inversions purify our blood. Also, the reverse action of gravity on the body encourages a rich supply of blood flow to the brain and eyes nourishing the neurons and flushing out toxins. This is believed to enhance our concentration and mental capacity. Enriched blood flow is also directed toward the throat where we house our master glands; the pituitary, pineal, and thyroid are brought into balance particularly by the practice of shoulderstand balancing our entire endocrine system.
The fountain of youth (the esoteric side of inversions)
In Yoga philosophy we have a “nectar of life” called Amritabindu that we store in our crown chakra.
It is written that after taking food, the blood absorbs the nutrients and after 32 days 1 drop of new blood is made. It takes 32 drops of this new blood to make one single drop of Amritabindu (vital life nectar). This amritabindhu is stored in the Sahasrara (crown) chakra. Our amritabindhu can be depleted by living badly, eating badly, and thinking negative thoughts—it begins to travel downwards and is consumed by the upward flow of agni (our digestive fire) at the third chakra. When amritabindhu is lost, life itself is lost.
The practice of inverted asana (particularly sarvangasana (shoulderstand) and sirsasana (headstand) are the method for storing our amritabindhu. When we are inverted our amritabindhu remains safely in Sahasrara chakra, its downward flow is prevented—leading to an extension of our life span. The agni always travels in an upward direction, in the inverted asana it travels towards the anus cleansing and purifying the organs of digestion and the rectum/anus. If mula bandha is strong and the digestive fire can travel all the way to the anus and the Muladhara chakra (root chakra) it will stimulate the release of Traya Granthis (knots that block our energy flow) and begin the gradual process of awakening our Kundalini energy.
Excerpts from Astanga Yoga by Lino Miele
Breathing while inverted
Half inversions such as down dog and standing forward bends aid the exhale, the weight of the abdominal organs against the underside of the diaphragm causes you to exhale more completely and correctly, maximizing the exchange of carbon dioxide and oxygen. This is even more pronounced in full inversions—gravity is pushing the abdominal organs onto the diaphragm lengthening the muscular fibers nearly to their maximum giving us a deep exhale and a deeper “detoxing” of carbon dioxide which makes space for more oxygen to come in on the next inhale giving us a deep and satisfying inhale.
Inversions actually prevent chest and backward breathing; the muscles that are responsible to breathe incorrectly are busy supporting the inversion! And therefore unable to help breathe incorrectly!
Also while inverted the inhale will be working the diaphragm harder to push the organs inferiorly (toward the ceiling) as it draws air into the lungs; this strengthens the diaphragm. Even students with the worst breathing habits in upright postures will have better breathing habits while inverted.
If Ashtanga yoga is practiced to a level of competence then the finishing asana (inversions) should be performed at the end of each practice, even if the practice stops after Surya Namaskar or part way through.