WHO THIS IS FOR
IS THIS YOU?
The sportive and long-ride rider
You're riding 2+ hours and bonking or fading in the back third.
The racer chasing higher intake
You've heard pros take 120g/hr and want to know if you should too.
THE ROADMAN VIEW
The Roadman view
The headlines did amateurs a disservice. When the pros started fuelling at 120g of carbs an hour and winning Grand Tours on it, the cycling internet decided everyone should. Anthony sat down with sports nutritionist Dr Sam Impey on the podcast, and the message was blunt: the 120g rule fails most amateurs, because their guts have never been trained to absorb anywhere near that.
Carbohydrate absorption is trainable, like any other system. The pros didn't arrive at 120g overnight — they built tolerance over months with specific glucose-fructose ratios that use two separate gut transporters. Take that number cold on a sportive and you'll spend the back half of the ride fighting your stomach, not the climb.
The honest default is 60g an hour for anything over 90 minutes. It's enough to defend your power, it's tolerable for almost everyone, and it's the floor the evidence supports. If you want to go higher for racing, that's a training project of its own — done in the weeks before, not on the start line.
EXPERT EVIDENCE
WHAT THE EXPERTS SAY
- Dr Sam ImpeySports nutritionist
The pro 120g/hr figure is real but conditional. It depends on a trained gut and the right glucose-to-fructose ratio. Prescribing it to amateurs without that preparation is why so many blow up — their absorption simply can't keep pace with the intake.
Hear it: Why Pros' 120g Carb Rule Fails Amateurs | Roadman Cycling - Optimal fuelling on the bikeRoadman podcast — under- vs optimal- vs over-fuelling
Under-fuelling caps your power and ends in a bonk; over-fuelling buys nothing and risks GI distress. The optimal band for most amateurs sits around 60g/hr, climbing only with practice.
Hear it: Under vs Optimal vs Overfueling on the Bike | Roadman Cycling Podcast
PRACTICAL APPLICATION
DO THIS WEEK
Default to 60g/hr on long rides
Roughly two gels, or a gel plus a carb drink, or a banana plus a gel, every hour after the first 30–45 minutes. Set a recurring alarm on your head unit so you don't forget.
Start before you're empty
Begin fuelling at 30–45 minutes, not when you feel flat. By the time you feel the bonk coming, you're already two gels behind.
Train your gut if you want 90g+
If you race and want higher intake, practise it on long training rides for several weeks, using a 2:1 glucose-to-fructose product. Build from 60g toward 90g gradually — never debut a new intake on race day.
COMMON MISTAKES
WHAT CYCLISTS GET WRONG
MISTAKECopying the pro 120g/hr number without gut training.
FIXStart at 60g/hr and only build higher with weeks of practice and a glucose-fructose mix.
MISTAKEWaiting until you feel hungry or flat to start eating.
FIXFuel on a clock from the first 30–45 minutes. Once you've bonked, you can't fully recover mid-ride.
MISTAKEUsing only glucose-based products at high intake.
FIXPast ~60g/hr you need fructose alongside glucose to use a second transporter, or absorption stalls and your gut rebels.
FAQ
FREQUENTLY ASKED QUESTIONS
How many carbs per hour for a 100km sportive?
Do I need carbs for rides under an hour?
What's the best source of carbs while cycling?
Can I really absorb 120g of carbs per hour?
Will high carb intake cause stomach problems?
Should I fuel differently for fasted training?
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