Kriya means a process by which we clean the body using particular yoga purification practices. Diferent Kriyas are designed to purify all levels of life: physical, mental and spiritual.
Kriyas are the techniques aimed at cleansing the body. The word kriya means “action”. Kriyas are not necessary if you know how to do proper asana and pranayama. Kriyas should not be practiced as a daily routine. They should be practiced only if there is need to balance some aspect of our physiology which is out of its proper function and if the channels of our body are blocked with impurities. Doing Kriyas everyday, without proper indication of their need, will create imbalances in the physiology.
Kriyas can also be performed in connection with asanas. This makes an asana more intense, but at the same time also more limited. These kriyas can be considered as the dynamic, fragmentary actions of a more general and comprehensive plan, laid out in the enfoldment of the asana itself. Kriyas can be practiced as preparatory movements for the asanas or they can be performed, at a more advanced stage of the practice, as a way of generating more prana within the energy pattern, delineated by the asanas. When we do pranayama we are using air and fire (agni) to clean the body. Kriyas are techniques which promote powerful localized energy movements. The purpose of Kriyas is, by bringing kapha dosha in balance, to prepare the body for practicing asana, pranayama, bandhas and mudras.
Some important kriyas are: Agnisara kriya, Ashta Sandhi Vimochana Kriya, Baddha Hasta Kriya, Bhujangini Kriya, Nauli Kriya, Prishtha Tadana Kriya, Sarpa Kriya, Ushtra Kriya, etc.
Courses on kriyas:
Course on Shatkarma
Course on Shankaprakshalana
Course on Nadi Sutra Kriya
Course on Kaya Kalpa