by Neil Anderson
Exercise breaks your body down.
It breaks down energy levels. It breaks down micro-processes that control immunity. It even literally breaks down muscle tissue. Exercise scares the hell out of your bodies primitive survival instincts.
Your body doesn't want to walk around in a broken down state. Its primitive programming thinks if you happen to be walking around in a "broken down" state and a sabre toothed tiger attacks the group of people you happen to be standing around with, YOU as the most broken down and therefore the weakest, are most likely to be killed and eaten by the tiger.
It doesn't just fear tigers. It feels the same way about bacteria and other diseases. If you are standing near a person with a horrible disease, your body wants to have all the energy it needs to fight off the disorder should it be contagious. It is a basic law of self-preservation.
Working out literally puts your body into a panic mode. After exercising, your body will do all it can to bring your own resistance and energy back up to baseline to potentially protect itself from sabre toothed tigers and awful diseases. If you do this often enough (more consistency is better), your body will try to outsmart you. It will build your previous energy and resistance levels way up. It will do this to the point that even after a GPP “soul crusher” your levels are still above your previous baseline (or maybe just not as far below baseline for as long). Understanding how to manipulate this cycle is exactly how we use exercise to INCREASE resistance and energy. We call these increases "fitness."