Marathons are hard because of the physical pain, the pounding on the muscles, joints, tendons.

The greatest evil is physical pain.

The only antidote to mental suffering is physical pain.

Pain is temporary. It may last a minute, or an hour, or a day, or a year, but eventually it will subside and something else will take its place. If I quit, however, it lasts forever.

If you worried about falling off the bike, you’d never get on.

I've certainly experienced physical pain in my life.