16/09/2026
The pre-HYROX breakfast everyone thinks is “healthy” is often the exact thing that gets them in trouble mid-session.
Big bowl of oats, banana, apple, a scoop of protein. High fibre, high fructose, high protein, all in one sitting, all in the window where your gut has the least capacity to handle it.
Here’s the physiology: during intense exercise, blood flow shifts away from your digestive system toward working muscle. Gastric emptying slows down. Anything high in fibre, fat, or FODMAPs that’s still sitting in your gut starts fermenting instead of digesting. That’s what shows up as cramping, urgency, or worse, mid-competition.
A 2025 systematic review in the Journal of the International Society of Sports Nutrition found that low-fibre, low-fat, low-FODMAP eating in the 24 hours before competition is one of the few strategies with consistent evidence behind it.
A separate 2025 case series in the International Journal of Sport Nutrition and Exercise Metabolism used a high-carb, low-FODMAP approach to resolve chronic GI symptoms in endurance athletes.
What to actually eat before HYROX:
3-4 hours before: white rice, plain pasta, white toast, eggs, a ripe banana
60-90 minutes before: rice cakes, honey on white toast, or a sports drink
Avoid: wholegrains, legumes, cruciferous veg, large amounts of high-FODMAP fruit (apple, pear, mango), creamy or fried food, and anything you haven’t already trained with.
The rule that matters most: nothing new on race day. If you haven’t eaten it before a training session, don’t eat it before the competition.
Save this for your next Hyrox prep.
(If you have a diagnosed GI condition, work through this with your own practitioner rather than a general protocol.)
🏃🏻♂️
