George Foreman

In boxing, I had a lot of fear. Fear was good. But, for the first time, in the bout with Muhammad Ali, I didn't have any fear. I thought, 'This is easy. This is what I've been waiting for'. No fear at all. No nervousness. And I lost.

It's not just the physical aspect of boxing, it's the whole fighter mentality that has been ingrained in me through the years as a competitive athlete. One of the hardest things you'll ever do is to box - to get into the ring and to face off with somebody whose whole goal is to knock you out, to hurt you, and to be able to fight back.