योग: चित्त वृत्ति निरोध:॥
Kriya refers to a set of practices, mainly breath control techniques and exercises, Kriya are practiced to achieve a specific outcome. The word is a Sanskrit term that means “completed action”. It is meant for the subtle body of the human being, as per Indian traditional philosophy. Kriya is concerned with loosening up the joints of the body. It eliminates energy blockages and outer extremities of the physical body and works on the Pranic and the mental level as well. It involve breathing techniques, sound and physical poses. Each kriya is aimed at a specific outcome and has very specific instructions by guru, such as the amount of time to hold each pose, point of eye contact and breath technique.
Ashwini kriya works both externally and internally, or, in other words, on the level of the physical body and on the energy level. Ashwini kriya simply told, is the rhythmic contraction of the anal sphincter muscles, the sphincter muscles are the ring like muscles surrounding the anus.
This simple practice can help you get rid of constipation, deals with diseases of the rectum and hemorrhoids, and will improve your health. Since it stimulates the prana flow toward the upper part of the body, it slows down theaging process and improves the health in general. It also makes your body more resistant to diseases if you practice this yoga kriya regularly.
On a more subtle level, it increases the awareness, makes your mind more peaceful, gives more energy, and can even improve your mood.