Stress and railways

In both services I offer - yoga and massage, I focus first on the level of stress my clients carry within their bodies and minds. A simple muscle testing techniques allows me to assess how well is the diaphragm muscle working. A proper diaphragmatic breathing is an essential for a stress relief. 
Someone very clever once said that if you cannot explain something clearly to a 6 year old child then you don't understand it yourself. So after I test my clients at the beginning of a massage appointment I look for the best words to describe the two branches of our autonomic nervous system - one responsible for the smooth operation of pretty much everything in the body and promoting the natural state in which our bodies can rest, digest and heal in peace; and the the other one which is responsible for emergencies when certain functions in the body need to be shut down in order to deal with the threat (real one or not). The picture of the nervous system as a railway came to my mind. On one hand the very efficient and dense railway system represents the parasymphatetic nervous system and the emergency railway lines which represent the symphatetic nervous system. A little bit like the Swiss or German railways versus the Australian railways. The dense and efficient one goes everywhere around the body delivering messages and goods and if something is missing the next train will have it! The fast one - the emergency one, comes on board during emergencies. It shuts down a lot of the connections of the other railways and focuses on only few essentials in order to fight or get us away from the emergency. Muscles are pumped and ready, heart is racing and the ability to focus is high. It's needed! But after the emergency the other railway should be automatically opened again. And that is when the diaphragmatic breath comes in because it is the main switch to get you back from the emergency response to the natural state of wellbeing (and get everything within your body to function like the German railways).
When our  ancestors encountered a thread they either fought it or ran away from it. If they survived they would be out of breath for a while from either the fighting or running. And this intensive abdominal breath would switch them back into the 'normal' state. 
And what is the moral? Take 10 deep abdominal breaths whenever you think of it!