Introduction: Fuel Smart, Race Strong
The 24 hours before HYROX determine how well you perform.
Your nutrition choices can mean the difference between steady pacing and an early crash.
Pre-race fuelling isn’t about loading up it’s about optimising energy availability, hydration, and gut comfort.
“You can’t out-train poor race-day fuel.” — RB100.Fitness
This guide breaks down what to eat the night before, on race morning, and in the final hour before the start.
1. The Night Before: Build Glycogen, Not Bloat
HYROX demands both aerobic endurance and muscular strength.
You want high glycogen stores but an empty, comfortable stomach.
Goals:
- Top up carbs without overdoing fibre or fat.
- Stay hydrated with electrolytes.
- Eat your final meal 2–3 hours before bed.
Ideal Pre-Race Dinner:
- 120–150 g carbs (rice, pasta, potatoes)
- 25–30 g protein (chicken, fish, tofu)
- Minimal fat or heavy sauces
- Include sodium (salt lightly)
Example Meal:
Grilled chicken, white rice, and mixed vegetables + electrolyte drink.
Avoid:
- High-fibre foods (beans, broccoli, large salads)
- Alcohol and excessive caffeine
- New foods your gut hasn’t handled before
Linked reading: HYROX Nutrition Guide: Fuelling Strength, Speed & Endurance

2. Race Morning: Calm Energy, Not Chaos
Breakfast sets your energy rhythm for the entire race.
Eat 2.5–3 hours before your heat to allow digestion and blood-sugar stability.
Goals:
- 1–3 g carbohydrate per kg bodyweight
- Moderate protein (~20 g)
- Low fat and fibre
- 500–750 ml fluids with electrolytes
Example Breakfasts:
- Porridge with honey, banana, and a scoop of whey
- White bagel with jam + Greek yoghurt
- Rice with egg whites and soy sauce (popular in endurance sports)
Keep it simple — this is not the day for experimenting.
3. One Hour Before: Light Top-Up
30–60 minutes pre-race, focus on fast fuel and hydration.
This is your last window to stabilise blood sugar and prime performance.
Options:
- Half an energy gel or small banana
- 200–300 ml isotonic drink
- Optional caffeine (3 mg/kg) if tested in training
Avoid anything heavy or unfamiliar.
If your stomach feels unsettled, small sips of electrolyte solution are enough.
“You don’t want to feel full you want to feel ready.” — RB100.Fitness
4. Race Hydration Plan
Hydration starts the day before.
For morning races, sip 400–600 ml water with electrolytes before breakfast, then taper fluid intake to avoid bloating.
Guidelines:
- 5–7 ml water per kg bodyweight in the 4 hours before start
- Add sodium (400–600 mg per 500 ml)
- Avoid drinking excessively in the final 15 minutes
Linked reading: HYROX Hydration Strategy: Fueling the 8 km Race

5. Common Mistakes to Avoid
| Mistake | Problem | Fix |
|---|---|---|
| Overeating breakfast | Gut distress, cramps | 2–3 h gap pre-race |
| Too little salt | Premature fatigue | Add electrolytes day before |
| New supplements | Unpredictable digestion | Stick to tested products |
| No pre-hydration | Early heart-rate spike | Start sipping fluids early |
6. Bonus: Evening Before Checklist
- Eat balanced, moderate-carb dinner
- Prepare breakfast ingredients the night before
- Pre-mix electrolyte bottle and race gels
- Avoid alcohol and late-night heavy meals
- Aim for 7–9 hours of sleep
Linked reading: HYROX Race Week Checklist: Fuel, Sleep, and Load Management
Summary: Eat to Flow, Not to Fight
HYROX nutrition is about composure.
Fuel smoothly, hydrate steadily, and avoid digestive surprises.
When you start calm and nourished, you race with confidence and control.
“A great race starts the night before.” — RB100.Fitness
About HYROX Season 2025 / 2026
- Season runs September 2025 – June 2026
- Global standard format: 8 runs + 8 functional stations
- Smart fuelling gives consistency across every heat
Plan your race via the RB100 Fitness Racing Events Calendar











