One thing I have learned is that you can run a marathon with cramps but you will pay for it afterwards. Several times now I have been able to complete Ironman without any day-after pain or soreness. In all cases, I was able to exercise the next day. No, this is not due to some magical pill or potion, just good old training. It is also not due to lack of intensity. Those last Ironman races were new PR's and I made significant gains in both.
However, a few years ago I had very bad cramps on the bike in Wildflower. I ended up walking and jogging the entire half marathon (Wildflower is a half-ironman race). Afterwards I paid for it. I was sore for a whole week. Sore, stiff and almost unable to walk. It is the price you pay for continuing to race when your body tells you to stop.
As for cramps I also learned now that dehydration has little to do with it. I did not grab for salt tablets and did not start drinking excessively. That was good, because the cramps came and went as they always do with little or no difference. The key benefit was that I did not get an upset stomach on top of it as I had many times before when I tried to "cure" my cramps by guzzling water and eating salt.
Apart from the soreness, my blue toenails are the most painful memory. Ironically enough I never knew about the toe condition during the race. I only "discovered" it in the shower. It reminded me of all the shoulder bruises I discovered after I went skydiving a few years ago. There are some magical effects of adrenalin.
Yesterday I swam 1,500 meters. It felt good.
The ironman raised nearly $14,000 for the brain aneurysm foundation.