So…my last IM resulted in diarrhea on the run (could still finish fortunately) with no “warning signs” beforehand.
Previous races had been good with only some occassional “bloat feeling” when i ate too much gels on the run.
The easiest explanation would be i just shot beyond my tolerance level in terms of carbs. I estimate my consumption was ca. 85g per hour while in previous races i couldn’t go much beyond 60g. For unknown reasons this time it was no problem to get it in.
Basically i am wondering how to narrow down possible explanations - apparently there are multiple factors. Here are some ideas, what do you think?
Pre-Race:
Reduce fiber intake on previous day(s) → i do carb loading, but not explicitly limiting fibers. So better e.g. skip vegetables on my pasta, would it matter?
?Race, on the bike:
(see above, limit total consumption to tolerable level)Replace solid food by liquid-ish stuff → i ate 4 classic powerbars on the bike plus one (or two? cannot remember) maurten 160 bars → should i switch to high-concentrated drinks, gels or e.g. gummies?Reduce caffeine → i ate 3 white (caffeine) maurten gels – too much?More sodium → Didn’t consume any salt
Change the order or frequency of nutrition intake → smaller bites, more often?
Test, test, test. I know that may not be what you are looking for, but come race day I just do what I have tested (many, many times) and I know it works. Of course there are basic principles to follow, which there are plenty of here and elsewhere . . . but you must test it individually for you.
Your post sounds like this was not your first IM. What did you do on the other one(s) where you didn’t have this issue?
The core difference was this time i had more appetite and had no issues to get in more nutrition (vs. previous races). However, the “incident” makes me now re-evaluate the whole nutrition concept - maybe it was never well balanced and i should consider as well modern options (stuff like Maurten 320).
Your post sounds like this was not your first IM. What did you do on the other one(s) where you didn’t have this issue?
The core difference was this time i had more appetite and had no issues to get in more nutrition (vs. previous races). However, the “incident” makes me now re-evaluate the whole nutrition concept - maybe it was never well balanced and i should consider as well modern options (stuff like Maurten 320).
If you had not tried that form of nutrition, or that much in training, then yes - I would test and adjust that first. But if you are normally good with that, then you might also evaluate what you ate leading up to the race. I pretty much avoid any restaurant food the day before. There was one year I could confirm I ate something bad because my friends who were not racing also felt ill.