Although every exercise is a mind game, I feel it the most in my heavier sets. Of course we want to break through and get those "extra sets" that Tom Platz talks about. "...when you're squatting 500 for reps and you can't get one more but grunt out ten. Your nose starts bleeding, you fall into the rack and that's set one." This is the shit we strive for.
The lifting high comes from this mindset. There is more strength inside of you than you know. Psyching yourself up, tricking your brain by not doing the gym math with whats on the bar, or just not looking at it before you lift it,
We have to play the game to beat our minds, or our minds will beat us in the gym. Now, go lift more than your mind thinks you can.