The vital or etheric sheath (the pranic body) supplies energy and vitalizes the physical body. It is roughly the same size and form as the human body. There are three sheaths that make up the astral body.
Further, the vital sheath is made up of five pranas (life-energies) that each serve a different purpose in the physical body's operation.
Vyana, which means "outward moving air," is the vital air that governs the body's general motions and coordinates the other vital airs. It pervades every cell in the body.
Udana, or 'upward flowing air,' works between the throat and the top of the head, stimulating the sensory organs such as the eyes, nose, ears, and tongue.
It moves upward, carrying kundalini shakti (a person's potential spiritual energy or vital energy force, which is latent at the base of the spine in the muladhara chakra or base energy center).
When the primary subtle nerve channel (sushumna nadi) at the center of the spinal cord is awakened, this creative, vital energy force flows to the crown chakra (sahasrara), the seventh energy center at the crown of the skull.
The astral body is separated from the bodily form by udana during death.
Prana (life-sustaining energy) is a manifestation of cosmic prana (the cosmic life-energy that pervades both the macrocosmic universe and the microcosmic unit of the body). The medulla oblongata at the base of the brain is where cosmic prana enters the body.
The vital airs (vayus — pranic air currents) descend and ascend through the astral spine, where they are transformed by the chakras and distinguished. Prana, or "forward flowing air," activates breathing between the neck and the top of the diaphragm.
The kundalini shakti is also raised to udana.
Prana (life-sustaining energy) is a manifestation of cosmic prana (the cosmic life-energy that pervades both the macrocosmic universe and the microcosmic unit of the body).
The medulla oblongata at the base of the brain is where cosmic prana enters the body. The vital airs (vayus — pranic air currents) descend and ascend through the astral spine, where they are transformed by the chakras and distinguished. Prana, or "forward flowing air," activates breathing between the neck and the top of the diaphragm.
The kundalini shakti is also raised to udana.
The digestive system, the heart, and the circulatory system are all activated and controlled by Samana, which works in the abdominal area between the navel and the heart.
Apana, which means 'air that flows away,' activates ejection and excretion from the navel to the feet.
It moves downward, yet it raises the kundalini to join with the prana. These five vital airs (vayus) are linked to the five subtle action organs (speech, hands, legs, organs of evacuation, and procreation), which have gross bodily analogues.
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