I finished the Seattle Marathon on Sun, 11/27/2005. My time was a pretty unimpressive 4 hours 36 minutes, but I am very happy that I finished. I was training for 5-6 months and I thought I would be O.K., but this was my first marathon and I didn't really know what to expect.
Some things I noticed from this experience:
1) The training book I was following (Marathon: The Ultimate Training Guide by Hal Higdon) advised to run not more than 20 miles while training for your first marathon. The intent was to minimize your chance for injury. The author argued that for your first marathon, you should go in slightly undertrained, because your main goal is to finish, not set any records. Being slightly undertrained gives you an advantage over being exhausted before you start or not being able to race at all because you pulled a muscle or something. I don't know if this was good advice or not. I did finish so he was probably right, but I felt like I should have trained harder so that I could have finished faster or with less pain.
2) This hurt much worse than I thought it was going to. I had never even run 26 miles before so I was in new territory at the end of the race. I planned on being seriously fatigued, but I did not expect to hurt so much. My thighs cramped up some and during the last few miles, a jolt of pain went up my leg every time my foot hit the ground. Ouch. That never happened to me before, so it was a new experience...
3) There are clearly some tactics involved. I deliberately started out very slowly, but I felt good, so I picked up the pace some during the middle of the course. That was a mistake. I felt fine until around mile 16. After that, I noticed that I was slowing down, almost imperceptably at first, then gradually slower and slower. By mile 20, I was in survival mode. It was really interesting how quickly I went from cruising to hurting really bad.
4) Overall it was a blast. I haven't hurt this bad since my rock-climbing days. It really makes you feel alive.