Kriya means Movements taken as catabolism and anabolism in Ayurveda. Kriya Sharir (Ayurveda Physiology) is the key subject of medical sciences. This science deals with the basic functional aspects of human body. The main aim of ayurveda is to acquire purushartha by means of Dharma, Artha, Kam, and Moksha. For this purpose, each person should be healthy in terms of body & mind. The defination of healthy person according to ayurveda is to balance Dosha, Dhatu, Mala,Agni, Kriya, Prasanna Atma, Indriya, & Man. Kriya Sharir deals with various bodily systems such as the digestive system, reproductive system and much more, which together are essential for a physician to know for correct diagnosis and treatment. It conveys basic Ayurvedic concepts like Dosha-Dhatu-Mala, Pachana, Prakruti, Atma, Mana etc. If one understands the normal processes of body i.e. Kriya Sharir, it is easy to understand Ayurvedic pathological and pharmacological changes; and further Ayurvedic medicine.
Ayurveda aims at preservation of health and curing of the disease. Ayurveda emphasizes more on the normal condition of Jatharagni (digestive fire), that is why it has been mentioned as “Rogaha Sarvepi Mandagni” ie main reason for every disease is anomaly in digestive fire (Agni). The food undergoes metabolic transformation by Jatharagni and results in maintenance of the body tissue elements by their growth and repair processes. According to Charaka, Jatharagni is the leader of all the factors concern with digestion in the body of all living beings. Charaka also states the seat of Agni is also known as ‘Grahani’ because it receives and retains the food. Agni controls the catabolism and anabolism in the body. If ever this transformation hampers this eventually give rise to diseases as Agni is the root cause. Hence, Proper knowledge of normality is very much important for assessment of abnormality and later for selection of right treatment.
With clinical point of view in Ayurveda every individual is assessed with respect to their prakruti before treating any disease. Only then Vikruti (pathology) can be identified, this a major tool in ayurveda which every practioner needs worldwide.