"You don’t want to be caffeinated going straight into the race." - Tom Evans
UTMB is one of the most demanding races in endurance sport - not just physically, but nutritionally.
Long hours, overnight running and relentless elevation force athletes to think carefully about every detail before the race even begins.
For ultra runner Tom Evans, preparation is built around simplicity, timing and reducing risk wherever possible.
Speaking on his podcast, The Ultra Sound, Tom explained how his preparation begins several days before the race itself.
"One thing that I do for all races is I try and cut pretty much all fibre out of my diet three or four days before the race starts," he said.
"What fibre does is it likes to sit in your stomach and it also absorbs loads of water, so it's pretty heavy. You don't actually gain weight because it's not real weight, it's water weight, but you're still having to carry it round.
"It also sits in your stomach and bounces up and down - especially when you're running downhill - so it can be really aggravating and you do then get some real gastric issues. So I cut all of that out."
The result is a pre-race diet that Tom openly admits looks unusual from the outside.
"I'll have a smallish breakfast, a smallish lunch and then a smallish early dinner, but again I make sure I finish my last meal three hours before the race starts.
"And when I say 'breakfast' it's not a standard breakfast, it's more like a plate or rice with an egg for example, for a little bit of protein. But the vast majority is carbohydrate and it's all basically beige or white food!
"It's not the healthiest, I know, but it's what you need to do and it's only for three four days before a race."
Beyond food, Tom carefully manages how and when he uses caffeine.
"After that my preparation follows a similar pattern to all races - 90 minutes before the race I have sodium bicarbonate and then 60 to 30 minutes before the race I'll have a Red Bull.
"But for a race like UTMB I would probably end up having that Red Bull a little bit earlier because I don't want to be caffeinated going straight into the race."I want to reserve my caffeine for when I start getting tired and for when I really need it the most."
For Tom, the key is not just what works - but what’s repeatable.
The routine is tested in training, refined through experience and built around minimising surprises on race day.
Because in ultra-running, small details become very big details over time.
