A Journey Into Yin Yoga

76 A JOURNEY INTO YIN YOGA

astronauts in outer space. Without the positive stress of gravity on the body,

they experience loss of muscles mass and bone density. The factor that deter-

mines whether stress is negative or positive is whether the body perceives

the stressor as a threat. If it does perceive it as negative, the body shifts into

defensive mode. In summary, negative stress refers to any factor that causes

physical, mental, or emotional tension that disrupts the body’s equilibrium.

It is the precursor to disease.

The following list summarizes the functions and emotions related to the

sympathetic nervous system.

Functions

Protects the body against attack

Associated with fight or flight

Elevates blood pressure and blood sugar

Increases body heat

Regulates the brain, muscles, thyroid,

adrenal glands, insulin, cortisol, and

thyroid hormones

Emotions

Will

Anger

Desire

Fear

Irritability

Guilt

Depression

Parasympathetic Nervous System

The parasympathetic nervous system, in contrast to the sympathetic nervous

system, is responsible for energy recovery, regeneration, repair, and relaxation.

It is usually more active at nighttime. Some of the ways that it interacts with

the body are to stimulate the flow of saliva, slow the heartbeat, constrict the

lungs, stimulate digestion, stimulate the release of bile, and contract the bladder.

Generally speaking, the sympathetic nervous system is related to performance,

and the parasympathetic nervous system is related to rest and recovery.

“When you have a strong parasympathetic ner-

vous system, you are going down stream.”

—Dr. Michael Galitzer

The stronger your parasympathetic nervous system, the healthier you will

be. Any coach of a world-class athlete will tell you that the body becomes

stronger in a state of rest, not activity.