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How many carbs per hour should you eat on the bike?

Updated 2026-08-08 · The Peakfy coaching team

Road cyclist reaching into his jersey pocket for an energy gel while riding on a wet country lane
The hour you forget to eat is usually the hour the ride stops going well.

Most rides run well on roughly 30–60 g of carbohydrate per hour. On long or hard days, riders work toward 60–90 g/h — but only after training the gut to handle it. Under-fuelling is the quiet reason a good session falls apart in the last hour.

The dose, by how long and how hard you ride

  • Under about 75 minutes, easy: water is usually enough. Your muscles already hold the fuel for this.
  • One to two and a half hours, moderate: about 30–60 g of carbohydrate per hour.
  • Long rides, or anything at race intensity: work toward 60–90 g/h.

Those bands are not a target to hit perfectly. They are a floor to stay above. Riders far more often eat too little than too much, and the cost shows up late — the last climb of a five-hour ride, not the first.

Why the top of the range needs two sugars

Your gut can only move so much glucose per hour, because it uses one transporter to do it. Fructose uses a different one. Combine them — roughly two parts glucose to one part fructose — and you can absorb meaningfully more per hour without the bloated, sloshing feeling that ends rides.

This is why almost every modern drink mix and gel lists both. It is also why plain table sugar works: it is already about half glucose and half fructose. Dates, bananas and rice cakes are not a compromise, they are food that happens to be correctly formulated.

The gut is trainable, and it is the part most riders skip

Tolerating 90 g/h is a skill, not a setting. Riders who jump straight there on race day get exactly the stomach they deserve. The fix is unglamorous: add 10 g per hour to your long ride, hold it for a week or two, then add another 10.

Practise with the exact products you will use on the day, at the exact intensity. A gel that sits fine in Zone 2 can behave completely differently at threshold, when blood is being pulled away from your digestive system toward your legs.

Fluid and heat change the drink, not the carbs

In normal conditions, drink to thirst. In heat, drink more and add electrolytes — but keep the carbohydrate target where it was. The two decisions are separate, and blurring them is how riders end up either dehydrated or over-concentrated and nauseous.

One practical rule: if the fuel is in your bottle, heat means diluting it and taking additional plain fluid, not diluting your fuelling plan.

What you eat after matters for tomorrow, not today

Refuelling is where the next session is won. Muscle glycogen resynthesis is slow, which is why riders in heavy training blocks often start each day with stores well below full — a pattern described in the sport-science literature on glycogen metabolism for coaches and athletes (Sports Health, 2018).

The practical consequence is undramatic: for recovery over a day or more, the total amount of carbohydrate you eat matters more than the timing or the type.

Your numbers, explained the moment you ask.

Here is the part that trips people up: the right number changes with every session. A 90-minute endurance ride and a three-hour day with threshold work are different fuelling problems, and working it out on the morning of the ride is how it gets skipped.

Peakfy puts the fuelling on the session itself — carbohydrate per hour and fluid per hour, sitting next to the interval profile and the power and heart-rate targets, worked out from that ride's duration and intensity. Not a food diary. A number on the plan you were going to follow anyway.

Questions riders ask

Real food is fine, and often better tolerated. Gels, drink mix, bananas, dates and rice cakes all deliver carbohydrate. Choose by what your stomach accepts at intensity and what you can actually open with one hand.
Yes. Add roughly 10 g per hour to your long ride, hold it for a week or two, then add another 10. Use the products you plan to race with, at the intensity you plan to race at.
Usually the concentration is too high or the intensity is too hard for what you took. Take plain fluid alongside the fuel, drop back to smaller and more frequent portions, and build the amount up over weeks rather than in one ride.
Some riders do, under guidance, for specific adaptations. It is not a beginner tool, and it is the wrong approach for any session where the goal is quality. Fuel the work you are actually trying to do.

General sport-science guidance for healthy riders. Not medical advice.


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