Run when you can, walk if you have to, crawl if you must; just never give up.

Once you permit yourself to compromise, you fail yourself.

Unless you're not pushing yourself, you're not living to the fullest. You can't be afraid to fail, but unless you fail, you haven't pushed hard enough."

Adventure books are my personal favorites. 'The Endurance,' a story about Ernest Shackleton's legendary Antarctica expedition, or 'Into Thin Air,' Jon Krakauer's personal account of the 1996 disaster on Mt Everest, are two notables.

People think I'm crazy to put myself through such torture, though I would argue otherwise. Somewhere along the line we seem to have confused comfort with happiness... Dostoyevsky had it right: 'Suffering is the sole origin of consciousness.' Never are my senses more engaged than when the pain sets in. There is a magic in misery. Just ask any runner.

Don't confuse comfort with happiness.

When I ran across America, for 75 days I ate 10,000 calories a day. I still lost about five pounds.