Stephen King said this quote

Some of these guys will go on walking long after the laws of biochemistry and handicapping have gone by the boards. There was a guy last year that crawled for two miles at four miles an hour after both of his feet cramped up at the same time, you remember reading about that? Look at Olson, he's worn out but he keeps going. That goddam Barkovitch is running on high-octane hate and he just keeps going and he's as fresh as a daisy. I don't think I can do that. I'm not tired -not really tired- yet. But I will be. The scar stood out on the side of his haggard face as he looked ahead into the darkness And I think... when I get tired enough... I think I'll just sit down