Race-day fuelling: take what you have already tested

Fuel is a plan, not a ritual

Race fuelling starts days before the race. In the 24–48 hours before most endurance events, increasing the proportion of carbohydrate while keeping familiar foods and meal times is a common approach. There is no need to suddenly eat large amounts of unfamiliar food or to stuff yourself on race morning. A race-day breakfast is usually eaten 2–3 hours before the start, with easily digestible carbohydrate you already tolerate, a little protein and fluid.

If the start is very early or nerves make eating difficult, split breakfast into a larger meal further out and a smaller snack closer to the start. Rehearse it in training instead of copying someone else’s menu.

Carbohydrate during the race

The International Society of Sports Nutrition position stand suggests about 30–60 grams of carbohydrate per hour for extended high-intensity exercise lasting more than 60 minutes, often as a 6–8% carbohydrate-electrolyte drink taken in small amounts every 10–15 minutes. Adjust the amount to event duration, intensity, weather, gut tolerance and what worked in training.

Gels, drinks, chews and solid food all provide carbohydrate, but concentration, volume and absorption differ. “A gel every 20 minutes” means nothing until you know how many grams each product contains. Record the product, timing, weather and gut response in training, and use only tested combinations on race day.

Fluid and electrolytes

There is no single fluid volume for everyone. Combine temperature, humidity, sweat rate, aid stations and personal tolerance. Do not drink a large volume at once, and do not avoid all fluid to avoid toilets. Electrolyte drinks can replace some salt lost in sweat, but a stronger concentration is not automatically better; salt tablets and supplements are especially poor choices for a first race-day experiment.

If you develop bloating, nausea, vomiting, dizziness or marked palpitations, reduce intensity, adjust fuelling and seek medical help. Persistent vomiting or altered consciousness is not a “push through it” problem.

Aid stations and self-carried fuel

Check the race manual for aid-station locations, what is provided, waste zones and water. Do not assume every station has your product. If you carry your own, confirm whether bottles, belts or vests are allowed and where you can discard waste.

Write your fuelling times on your bib or watch, but do not follow the clock through a body that is clearly struggling. Heat, climbing or higher intensity can slow gastric emptying; the original plan may need to change.

The first meal after the finish

Start with fluid and carbohydrate, then add protein; if appetite is low, a carbohydrate-electrolyte drink can come before solid food. Recovery is not one meal. Sleep, normal meals and easy movement over the next 24–48 hours matter too.

Scope and limits

This page does not provide an individual nutrition prescription, therapeutic diet, fluid volume or medical clearance. People with diabetes, gastrointestinal disease, pregnancy, a history of disordered eating or medication should discuss race fuelling with a doctor or registered dietitian.

Sources and scope

The during-race carbohydrate range and timing follow the ISSN nutrient-timing position stand; pre-, during- and post-race nutrition follow the same stand and the ISSN carbohydrate-timing paper. These are sports-nutrition principles, not individual medical care or race clearance. Checked 2026-10-28.