The parasympathetic system (PNS) is responsible for the body’s “relaxation response,” the system that brings the body back in balance after the sympathetic nervous system’s response (from a stress stimuli) has passed. When the organism is constantly under stress, the autonomic system becomes used to sympathetic excitation. Most of us respond by using food as a stress management mechanism. This is the most common reason for weight gain.

With the practice of yoga or other mind-body approaches such as tai-chi or chi-kung, one is able to relax through the focused excitation of the PNS. By balancing the “mix” between the sympathetic and parasympathetic system, one is able to control the body’s physiological response to the environment at the cellular and chemical level. Practice, physiology, and “state of mind” affecting and shaping each other.