Yes, they were basically normal and well-adjusted powerlifters. The point is, this strange behavior trained their opponents to fear them on sight particularly important to them in their role of initial strike forces. Even more salient, they trained themselves to think they were tougher than they actually were. They were mortal, and they died in battle quite often. But they maintained the image.
Image is everything.
Train yourself to believe you are stronger. Attack the weight fiercely on your first two worksets, and continue to repeat these attacks until the iron bends to your will. Hold nothing in reserve. Tell yourself that you are strong. Decide on a specific goal for each competitive lift, and then concoct specific training lifts to shoot for that goal.