If you are a zebra grazing on the savannah, and you see the shadow of a lion on the grass. Your sympathetic nervous system kicks into gear, taking the blood away from the digestive system and sending it to the muscles so that you can run fast. This is the flight-or-fight reaction.
Very important for survival.
But not so important when we are cut off in traffic, or in an argument with somebody. So when our sympathetic nervous system is engaged, and we are ready to fight or run, our muscles tense.
See the connection with back pain?
We react to stress by tensing, and we stay tense keeping our back in spasm, which leads to chronic back pain.
Stress has all sorts of other bad effects, for example, suppressing our immune system, which lowers our defense against diseases.
Read a few sample pages from the book on Amazon here:
Why Zebras Don’t Get Ulcers, Third Edition
It is very interesting. I will write more about how to reduce stress later.