The vayus are the five winds or currents of energy in the body. They help to circulate prana throughout all the systems of the body and maintain their optimal functioning. From the top of the body to the bottom they are:
Circulates energy in the throat and head and is associated with speech and memory. It can be experienced by inhaling and imagining energy circulating throughout the head. Seeing, hearing, speaking, thinking, tasting and smelling are udana vayu activities.
Circulates energy in the chest and moves upwards. It is associated with respiration and can be felt as you inhale imagining the breath moving upwards from the chest toward the head. Eating, drinking and breathing are prana vayu activities.
Circulates energy in the abdomen and is associated with digestion and assimilation. Experience it by inhaling from the periphery of the body towards the abdomen and exhaling from the abdomen towards the periphery. Digesting is a samana vayu activity
Moves energy throughout the whole body and is associated with circulation. Experience it by inhaling and expanding from the center of the chest out toward the periphery of the body and exhaling from the periphery back toward the center. Vyana vayu helps to coordinate all the other vayus.
Circulates energy from the pelvis to the feet and is associated with elimination and child birth. It can be experienced by exhaling and imagining the energy moving downwards from the crown of the head to the feet. Exhaling, eliminating and sweating are apana vayu activities.