I've run one. I hit the "wall" at the 25Km (out of 42) mark - which was really weird, because I was doing 21Km runs 4 or 5 times a week leading up to it - and t

I've run one. I hit the "wall" at the 25Km (out of 42) mark - which was really weird, because I was doing 21Km runs 4 or 5 times a week leading up to it - and they were no problem! Once I got passed it was fine, up to the 39Km mark when I decided to walk for a bit. BAD DECISION! I walked for a few hundred meters, then went to start jogging again. No way. My body refused to start up! I had to do a weird shuffle-my-shoulders-in-a-circular-motion to get up a rhythm and work up back to a jog. Got a banana at the finish line. Best thing I ever tasted.