Running teaches you that there’s a difference between working hard and feeling bad. Consumer culture tries to teach us otherwise. How many television commercials talk about “making life easier”? If everything you knew about life came from TV, your goal would be to live the easiest, most comfortable and unchallenging life you possibly could. You would believe that the only good feelings are sensual pleasures such as the taste of a good soft drink and the fun of driving an expensive car and lying on the beach.

But it’s just not true. Challenging and testing your mind and body, even to the point of exhaustion, failure, and breakdown, can feel as wonderful as anything else life has to offer. I suppose the enjoyment of hard work is more of an acquired taste than the taste for pleasure and fun, but once you’ve acquired it, you’re blessed with more ways to feel good, and life is better. Harder and better.

— Dean Karnazes, 50/50