We often forget the power of the breath in our western yoga practice. There is nothing more powerful in one's asana practice than the Great Yogic Breath.
The Great Yogic Breath is the 3 part breath. It is often referred to as:
Maha = Great
Pranayama = Cultivation, direction and integration of universal life force
In all of the pranayama practices, Prana is what we are after: In Maha Pranayama, we inhale from the bottom of the body to the top of the body (first the low belly, then the midsection, then the upper lungs). We exhale from the top to the bottom (first the upper lungs, then the midsection, and then the low belly). The Prana (with a capital "P") travels in this way... up the body on the inhale, and down the body on the exhale. (Note: this is not to be confused with the five pranas, or vayus of the body, which are different than the Prana about which I am speaking.)
Prana may be obtained from the air we breath, the food we eat, and the water we drink. The three part yogic breath is a basic, yet advanced and profound way to access, generate, and move this amazing cosmic consciousness: Prana.
All is vibration. From the tiniest atom to the greatest sun, everything is in a state of vibration. In all vibration is to be found a certain rhythm, and rhythm pervades the universe. Our bodies are as much subject to rhythmic laws as is the planet in its revolution around the sun. By falling in with the rhythm of the body, the yogi(ni) manages to absorb a great amount of Prana, which he/she disposes of to bring about desired results.
The general principles of the Great Yogic Breath may be summed up in the old Hindu saying: "Blessed is the Yogi who can breathe through his bones." The practice of Maha Pranayama will fill the entire system with Prana. It is a general housecleaning of all of the tissues in the body, and he who practices it carefully will feel as though he has been given a new body, freshly created, from the crown of his head to the tips of his toes.
Note: The two previous paragraphs are exerts taken from a book published in 1905, writted by Yogi Ramacharaka, entitled Hatha Yoga - or the - Yogi Philosophy of Physical Well-Being.
Let the practice itself be your teacher.