Learning to relax can offset the physical and mental effects of the Flight or Fight response.
How does the Flight or Fight response work?
- A threat is perceived
- The autonomic nervous system automatically puts body on alert.
- The adrenal cortex automatically releases stress hormones.
- The heart automatically beats harder and more rapidly.
- Breathing automatically becomes more rapid.
- Thyroid gland automatically stimulates the metabolism.
- Larger muscles automatically receive more oxygenated blood.
- The important thing to take away is that the fight or flight response is anautomatic response.
Even though the fight or flight response is automatic, it isn't always accurate. In fact most of the time when the fight or flight response is triggered it is a false alarm - there is no threat to survival. The part of the brain the initiates the automatic part of the fight or flight response, the amygdala, can't distinguish between a real threat and a perceived threat.
Chill, no, freeze!
Sometimes the perceived threat is so intense it triggers a "freeze" response. This could be interpreted as the brain being overwhelmed by the threat, or it could also be an adaptive / positive response to a threat. It probably evolved in humans and animals as a way of "keeping still" so a predator's attention would not be triggered by movement.
Either way, for modern humans the freeze response means that the muscles remain tensed and poised for action....action that is never really initiated. That's why we often get "knots" in our backs, shoulders, neck, and arms. We have not discharged the tension.