Race-day fueling: before, during, and after a race

Race day doesn't start at the gun. It begins 48 hours earlier. In this guide, I outline the complete fueling timeline from two days before your target competition to 24 hours after. No vague guidelines, but concrete time blocks with exact dosages. For the broader theoretical basis, I refer to my pillar guide on carbohydrates during exercise.

48-36 hours before: initiate carb loading

For target efforts lasting more than 90 minutes, glycogen maximization is beneficial. Burke and colleagues confirmed in their 2011 IOC consensus that carb loading 24 to 48 hours before competition brings your liver and muscle glycogen to their maximum.

The practical dosages:

• 8 to 10g carbohydrates per kilogram of body weight per day
• Spread over 4 to 5 meals plus snacks
• Avoid high fiber (disrupts digestion)
• Avoid new foods (no experiments)

For an athlete weighing 70kg, this means 560 to 700g of carbs per day. Translated into food: 300g white rice (90g carbs), 200g pasta (160g carbs), 4 bananas (100g carbs), 6 slices white bread (120g carbs), 200ml juice (30g carbs), 1 serving oatmeal (60g carbs), 4 Eagle bars as a snack (80g carbs). Total: 640g. Goal achieved.

Remember: this is for long competitions. For efforts under 90 minutes, carb loading has no proven added value. Just eat normally then.

The evening before: the last high-carbohydrate moment

Dinner the day before your competition is your last major refueling opportunity. Practically:

• Eat 6 PM to 9 PM (early enough to digest)
• 2 to 4g carbs per kilo in this meal
• Low in fat and fiber (no pizza, no whole wheat pasta)
• Familiar food (no Thai or spicy on the eve)

Classic example: white pasta with a light tomato sauce, a piece of chicken fillet, a banana for dessert. Not sexy but reliable.

3 to 4 hours before the start: pre-race meal

This is your last big meal. Burke 2011 and Jeukendrup 2014 recommend:

• 1 to 4g carbs per kilo
• Low in fat (slows gastric emptying)
• Low in fiber (causes GI issues)
• Moderate in protein (20 to 30g)
• 500ml fluid during this meal

Standard pre-race examples:

• Oatmeal (60g) with honey (20g), banana (1 piece), low-fat yogurt (150g)
• White rice (100g dry) with honey and cinnamon, plus an egg
• Pancakes (2 pieces) with maple syrup and banana
• Bagel with honey and banana plus a glass of fruit juice

All aimed at around 80 to 100g carbs. Enough to top up your glycogen, not heavy enough to slow you down at the start.

30 to 60 minutes before the start: final snack

The last fueling moment before you start. Keep it small:

• 30g carbohydrates as a final boost
• 1 Eagle bar or 1 gel is sufficient
• 200 to 300ml fluid (no excess, pee before start)
• Caffeine possible (Eagle BOOST or an espresso) if you are used to it

Important nuance: too much of a final snack can cause an insulin spike that inversely punishes you in the first 30 minutes of your effort (reactive hypoglycemia). Stick to 30g. Not 60g.

During the competition: the fueling framework

During the race, the rules from my guide on carbohydrates per hour apply. In short:

• Start within 30 min with the first fueling moment
• Dose every 20 to 30 min, not based on hunger
• 60 to 90g per hour depending on duration and training
• 2:1 glucose-fructose mix (Eagle bars + sports drink)
• 500 to 750ml fluid per hour
• Eagle BOOST in the final for caffeine boost

Caffeine timing: 50mg of caffeine from a BOOST bar peaks 30 to 45 minutes after ingestion. Do you want a caffeine boost for the last 30 minutes of your race? Take the BOOST 45 minutes before that moment.

Beyond the finish line: the first 30 minutes are critical

The recovery window is real. In the first 30 minutes after exercise, your muscles are extremely sensitive to the uptake of carbohydrates and amino acids. Burke 2011 and subsequent studies recommend:

• 1.0 to 1.2g carbs per kilo in the first 30 min (70kg = 70 to 84g)
• 0.3g protein per kilo (70kg = 21g protein)
• 500 to 750ml fluid plus salt for rehydration

Practically: a chocolate milk (300ml, 30g carbs + 12g protein) plus a banana (25g carbs) plus an Eagle bar (20g carbs) plus 500ml electrolyte drink. No complicated supplements needed.

The fructose magic in recovery: Fuchs 2019

Fuchs and colleagues showed in 2019 that post-workout fructose replenishes your liver glycogen 2 times faster than glucose. Glucose goes to your muscles, fructose to your liver. Replenishing both is a double win.

The practical application: mix a glucose source (chocolate milk, white rice) with a fructose source (fresh fruit, honey, fruit juice) in your post-workout meal. A banana and a glass of fruit juice next to your recovery shake do exactly that.

Liver glycogen is what you recover in the first 6 hours after strenuous exercise. Muscle glycogen only in the 24 hours that follow. Without fructose in your recovery, you leave the liver tank underfilled.

The rest of the day: refueling

After the first 30 minutes, your body recovers less quickly, but building up your glycogen stores remains a priority:

• Every 2 hours: 1.0 to 1.2g carbs per kilo
• Dinner: large portion of carbohydrates plus proteins
• Fluid and salt: 150% of estimated fluid loss
• Sleep: at least 8 hours, the most important recovery mechanism

A successful recovery day prevents you from under-fueling on your second training day afterward. For those training back-to-back or in multi-day competitions, this is the difference between lasting and collapsing.

The complete race-day timeline in one table

Scientific sources