What is high carb fueling?

High carb fueling means taking in enough carbohydrate before and during your ride to match the demands of the workout. Instead of waiting until you feel hungry or empty, you fuel early and consistently.

Research by Jeukendrup and others (2014) shows that carbohydrate intake during endurance exercise can improve performance, especially during longer and harder sessions. For many cyclists, a practical starting point is around 30 to 60 grams of carbohydrate per hour during prolonged rides. For sessions or events longer than 2.5 hours, research suggests that higher intakes of up to 90 grams per hour can be beneficial when tolerated.

In more recent years it has become increasingly common among well trained endurance athletes to consume 120 to 140 grams of carbohydrate per hour during long events. However it is important to understand that achieving this level of intake does not happen overnight. Your gut needs to be specifically trained to absorb and process that volume of carbohydrate without causing gastrointestinal distress, and this adaptation can take several months of consistent practice during training rides. Trying to jump straight to high carbohydrate intake on race day without prior gut training is a recipe for stomach issues at the worst possible moment. The key is not simply eating more. The goal is to absorb and use more fuel.

Why multiple carbohydrates matter

There is a limit to how much carbohydrate your gut can absorb from one type of carbohydrate alone. That is why many modern sports drinks and gels combine glucose or maltodextrin with fructose.
These are known as multiple transportable carbohydrates. They use different transporters in the intestine, allowing your body to absorb and oxidize more carbohydrate during exercise. Research has shown that this can increase carbohydrate availability, support performance, and reduce the chance of gastrointestinal problems when intake is high. For rides above 60 grams of carbohydrate per hour, a glucose-fructose mix is usually more effective than relying on one carbohydrate source.

Fuel the work required

Not every ride needs the same fueling strategy. An easy recovery ride under one hour may need little or no extra carbohydrate. A long endurance ride, hard interval session, race, or event requires more support. The longer and harder the session, the more important fueling becomes.
A simple guide:

• Easy ride under 60 minutes: often little or no extra fuel needed

• 1–2 hour endurance ride: around 30 grams per hour

• 2–3 hour ride or hard workout: around 60 grams per hour

• 3+ hour ride, race, or demanding event: 60–90 grams per hour, if trained and tolerated

These are starting points, not strict rules. Your needs depend on intensity, duration, heat, fitness, previous meals, and personal tolerance.

Train your gut

Your gut needs training too. Going from minimal fueling to 90 grams of carbohydrate per hour overnight is likely to cause problems. But research on gut training shows that practising carbohydrate intake during exercise can improve tolerance and reduce gastrointestinal discomfort. Start with an amount you can handle. Repeat it in training. Increase gradually. Test your fueling strategy before an important ride, not during it.
A practical approach: Start with 30 grams per hour on longer rides. Build toward 45–60 grams per hour for harder sessions. Only move toward 90 grams per hour when the ride is long enough to justify it and your gut can handle it.

The takeaway

High carb fueling is not about eating as much as possible. It is about matching your carbohydrate intake to the demands of your ride. Fuel early. Fuel consistently. Build gradually. Use the training rides in your JOIN plan to practise what works for you. Because when your training has structure and your fueling supports it, you can ride stronger, recover better, and get more out of every session.

Resources:

Jeukendrup A. (2014). A step towards personalized sports nutrition: carbohydrate intake during exercise. Sports medicine (Auckland, N.Z.), 44 Suppl 1(Suppl 1), S25–S33. https://doi.org/10.1007/s40279-014-0148-z