24hr Race Consistently Shut Down by GI Distress. Help!

Hey folx,

I just failed my third 24hr solo MTB race attempt due to GI distress. I had the legs and mind to keep going for another 12 hours, but it all shut down for me 12 hours in. The temperature wasn’t too warm throughout the day, and I progressively got colder and colder, watching my HR drop gradually, which is to be expected. I was fueling consistently with each hour, mainly Maurten, water and rice, but I had to stop and battled extreme bouts of vomiting throughout the remainder of the night.

Curious if anyone has knowledge about one’s body when they’ve packed too many carbs into their system, had the temperature drop, causing a perfect storm of complete performance shutdown.

This is my 6th solo race, where I’ve done 24hr hours straight 2 times before, winning the overall both times. Can’t remember what I had done differently other than I was a couple years younger and had slightly higher training volume. My first win the temperature was around 70º to start and dipped into the 30ºs at night, but I recall not being as ‘cold’ body temperature wise.

The race before my most recent fail, 24hrs in the Old Pueblo was similar in that the day started warm, I probably packed in too many carbs into my system, the temperature dropped, I couldn’t get my HR up and I got really cold. Followed by epic GI distress and vomiting. 12 hours max.

Can’t figure it out. Too many carbs? Body temp too low? Both?

I’ve ridden 2 24 HR solos in the UK and have been in a camp with other solos several times.
My instinct would be ditch the rice. That stuff breeds bacteria in certain conditions.
Secondly, drink / eat something warm. I have seen a lead rider bail on a race after eating cold rice pudding and then getting too cold to continue.
For me, drinking warm tea each lap is the thing that kept me going. It’s the thing that I look to forward to as well.