Next to flat out injuring yourself at the gym
, overtraining is one of the worst problems with working out
. Overtraining is a result of applying more stress
to your body
than it can adapt
to. As a result your body
to help adapt.
The cortisol scours your body for protein to break up into glucose. Since the whole purpose of working out at a gym is to build muscle mass (to impress the ladies no doubt), this is completely counter to any muscle-bound caveman's (nothing wrong with being one, however) goals.
Avoiding overtraining is simple, don't live at the gym! Spend no more than about an hour at the gym, and go at most every other day. A proper diet is vital as well.
I'll add some interesting research data on the effects of overtraining as I gather some interesting research data together.