Nutrition Response Testing is a structured form of autonomic nervous system (ANS) feedback testing.
It utilizes muscle testing, or applied kinesiology, to determine which tissues are stressed, which are the most stressed, and which supplements are best for the tissue and person.
Remember that the ANS is the part of the 
nervous system that works “autonomously”. It works without conscious control. For example, we cannot consciously make our heart stop beating or our digestive system to stop digesting, these activities occur automatically. There are two parts to the ANS: the sympathetic (“fight or flight”) and the parasympathetic (“rest and digest”). Both systems operate at the same time and have an effect on every organ and part of the body. When either system becomes imbalanced, or overly stressed, symptoms may occur. Symptoms may range on a spectrum of minor to severe, or subclinical to clinical. Since the ANS affects every part of our body, stimulation to nerve fibers of a particular organ that is stressed will reveal a weak muscle test. This is evident when contact on the area around an organ is made and a major muscle group is tested (such as the deltoids of the shoulder).
