The most common explanation given for the word prana in most of the texts is either “vital force” or “energy” but none of these words can precisely describe the deep meaning of prana. The term prana had emerged from higher states of contemplation referring to “livingness”, that is THE one energy which gives material form to everything in this universe. Whether it is a planet or an asteroid, an animal or a human, a grass or a tree, if there were no prana there would be no life into existence.
In Prashna Upanishad there is a discussion between the rishi Pippalada and his six disciples, who had reached his feet seeking for clarifications regarding their intellectual & spiritual doubts. One of the six questions deals with the creation of the universe, in which the rishi explains that everything in this universe are created by the pair of Prana (energy) & Rayi (matter). Prana is the energy that gives material form to everything. When we say form it does not mean only those that can be seen, but also all the subtle products that cannot be seen, like the thoughts created by the mind, for example or the blood circulation.
Nowadays, modern science has given sufficient data to us, especially with the theory of relativity, not to doubt on these declarations. According to scientists this earth, every one of the billions of individual cells of our body and every atom of matter began as an intangible form of energy. As far as science has been able to determine, the entire universe consists of but two elements, that is matter and energy. Nuclear scientists “cry” that matter is established, controlled and sustained by energy. Through the combination of energy and matter has been created everything that it is perceptible to us. What the science has found lately, regarding the composition of the universe, is exactly same with what the rishi had experienced after been in deep meditation states, i.e. energy (prana) gives material form to everything in this universe.
According to the Prashna Upanishad Sun is the presiding deity of energy (Prana)and Moon is the representative deity of matter (Rayi). Hatha Yoga is based on exactly same concept because the word HATHA is the combination of two beeja mantra(seed mantra, a particular vibration which has its origin in transcendental consciousness). The beeja mantra HA represents the sun, the energy (Prana), the vital force and the beeja mantra THA represents the moon, the matter (Rayi),the consciousness, the mental force. Both prana and consciousness must be present for the life to exist. Hence hatha yoga means the union of vital and mental forces, which permeate every atom and cell of the universe.
The Prana, the energy that gives material form to everything is also called Maha Prana – the great energy from which five primary forces (pancha prana) are emerged. These five forces that are also called prana vayus, function when the life resides in the body and they operate at all times to accomplish various body functions. The term vayus means “that which flow” and the prana vayu represent their flow in all the elements, organs and the mind.
The pancha vayu maintain the balance between the physical and the mental level and their physical locations are relevant in regard to the functions of the body.
Apana Vayu: Apana vayu is located in the lower portion of the body. It operates in the pelvic region, it is related to the earth and water elements and it is responsible for the expulsion of gas, feces, urine, semen and ova. It nourishes the fetus and it helps the uterus during the labour to give birth.
Prana Vayu: Prana vayu is located at the upper portion of the body and it is related to the sun. It operates in the thoracic region and it is the center of circulation of life energy. It is responsible for all chest activities such as breathing, swallowing and circulation of blood.
Samana Vayu: Samana vayu is located at the middle part of the body and it is related to the space between sun and earth. It is responsible for digestion and to maintain all nutrition and healthy life of all the cells in body. Samana vayu has a stabilizing role between prana and apana vayu.
Udana Vayu: Udana vayu operates in the extremities of the body, that is the arms and the legs and it directs the activities of the brain (vision, hearing, smell, sensation). Activities such as food & drink intake, vomiting, spitting, swallowing are all under the control of udana. Udana is related to the fire element because it gives warmth to the body. It also provides the motive force for the subtle body to move out of the physical structure at the moment of its death.
Vyana vayu: Vyana vayu pervades the whole body and acts as reserve energy. It gives extra boosting to all other pranas whenever it is required. It is related to the air element and it is responsible for all the muscles movements.
Everyone is born with a certain quantum of prana, but the quantity and the quality change continuously, as one goes in life. All Yogic practices generate higher levels of prana, but pranayama is the most effective, because it help us to expand the prana, regulate it properly and maintain its quantity in high levels.
Prana is the first principle that comes along our birth and the last which leaves us after death. Without prana there is no life into existence.