It's been a few years since I first read Dean Karnazes' Ultramarathon Man: Confessions of an All-Night Runner. Re-reading parts of it reminds how much I like this book:
"True, running is a simple, primitive act. Yet in its subtleties lies tremendous power. For in running, the muscles work a little harder, the blood flows a little faster, the heart beats a little stronger. Life becomes a little more vibrant, a little more intense. I like that.
"... I run because long after my footprints fade away, maybe I will have inspired a few to reject the easy path, hit the trails, put one foot in front of the other, and come to the same conclusion I did: I ran because it always take me where I want to go."