How You’re Getting Your High-Carb Fueling Wrong

Carbs! Carbs! More damn carbs!

That’s the war cry of the “carbohydrate revolution,” a performance fueling rethink that’s energized record speeds, Strava KOMs, and the wild aggression of the Pogačar era.

And while there’s no doubt that more carbohydrate is better, there can be too much of a good thing.

As Visma-Lease a Bike nutritionist Gabriel Martins warned us in summer:

“Let’s not jump on the bandwagon of everybody trying to fuel at 120 grams or 150 grams of carbohydrate because we hear Tadej or Jonas [Vingegaard] are doing it. Just because they benefit, not everybody does.”

Tim Podlogar, one of the kings of carbohydrate science and a consultant at Tudor Pro Cycling, served a similar reminder when speaking to Sportal this weekend.

The message?

Don’t get caught up in the hype of high-carb outliers like newly crowned Ironman world champion Casper Stornes, Unbound Gravel winner Cameron Jones, and iron-distance chuggers Kristian Blummenfelt and Cameron Wurf.

“These are trends that pop up from time to time, but as a scientist you often have to temper them a bit,” Podlogar told Sportal. “These trends can distract from what’s really important, and in the long run can even reduce athletes’ performance.”

Stornes recently fueled at an average 182g carb per hour for close to eight hours during his swim-bike-run around Nice.

Jones chowed an even more gut-churning 200g carb per hour to deliver a new course record of 8:37 last summer in the Flint Hills of Kansas.

“The trend of extremely high carbohydrate intake during a race has been carried over from the world of triathlon to cycling,” Podlogar said.

“The fact is that triathlon is a completely different sport than cycling, so adopting these approaches without understanding the background can cause a lot of damage,” he continued.

The complex science of carbohydrates

Podlogar has authored multiple leading carbohydrate studies and worked as a nutritionist at team Bora-Hansghrohe before he hooked up with Tudor.

Speaking to Sportal, he warned against us weekend warriors being inspired by the hyper-carb fueling headlines.

Even the WorldTour’s best rarely go much beyond the commonly accepted “carbohydrate ceiling” of 120g carbohydrate per hour.

“For riders Tadej Pogačar and Primož Roglič who weigh 60-70 kilograms, an intake of around 100 to 130 grams of carbohydrates per hour during the most difficult stages [of a grand tour] makes the most sense,” Podlogar said. “But certainly not 180 or even 200.”

So why 200g for some, but not others?

And how high-carb is too high carb?

The answer is annoyingly nuanced.

Podlogar explained to Velo that not even an eyecatching study published last month, which highlights the benefits of feeding at 120g per hour vs 60g or 90g, necessarily means pushing into three-digit carbs is always best.

So are you getting high-carb “wrong” with your three-dozen gel strategy?

Here are 3 reasons why you shouldn’t hop on to the super high-carb train and fuel as hard as the pros.

Plus, as a bonus, there’s also one surprising reason why, in some cases, you should maybe eat even more.

1: Relative intensity

Relative intensity is perhaps the most obvious factor that dictates fueling demands.

The metabolic fire needs to be roaring hot before you go stoking it with four gels an hour.

It’s thought that 50 percent of energy expenditure is an optimal replenishment rate, meaning a 250-watt ride would require fueling at around 100g carbohydrate per hour.

Contrastingly, Alpecin-Deceuninck steamroller Jonas Rickaert needed close to 175g per hour in his 400w breakaway with Mathieu van der Poel at the Tour de France.

Fueling with more than what’s needed is a waste of money and significantly increases the risk of G.I. distress.

Podlogar highlighted how even in the Mad Max intensity of the modern WorldTour, riders don’t endlessly guzzle to create an anti-bonk “safety net.”

“During a sprint stage, where the intensity is lower and energy expenditure is much lower, some cyclists take 120 grams of carbohydrates per hour, even though 80 grams would have been enough,” Podlogar said. “Then, when you do the math at the end of the day, it turns out that the energy intake was too high.

“Theoretically, that means they should ‘skip dinner,’ [to meet their prescribed nutrient targets] which would be a shot in the knee the day before a tough mountain stage,” Podlogar said.

As Velo explored in a deep dive on one team’s fueling strategy during the Tour de France, pros only fuel the work required.

A total of seven data sets showed daily fueling fluctuated between 85 and 133 gams of carbs per hour, tailored to the demand of the day.

So what merited the insane 200g per hour carb numbers of Wurf at Ironman Texas and Jones at Unbound?

“Iron Cam” Wurf set a world record with a 3:53, 46kph bike leg during his 7:40 redline effort this April. And Jones? He obliterated 200 miles of Kansas dirt with a monster 150-mile, ~4.0w/kg attack.

They rode hard, and they ate harder.

The high-carb conclusion?

If you’re pushing the pace, push the carbs, too. But unless you’ve got the watts of Wurf, you certainly won’t need to hit 200g.

Riding easy? Fuel easy.

For most amateurs riding at “chat pace,” 90g per hour is regarded as plenty.

2. Workload over time

The highest carb counts you see in endurance sports come in super-intense single-day races like Paris-Roubaix, Unbound Gravel, and Ironman triathlon.

Very similar stats spill out of the most grueling blocks of a grand tour.

But that’s largely because the outliers averaging 120g or more are thinking several days forward.

“Understanding the bigger picture is key – you always have to know what’s coming next day, you can’t just focus on the current stage,” Podlogar told Sportal. “Energy balance is a very sensitive thing in cycling.”

Visma staffer Martins explained to Velo that the “day by day” of a grand tour means energy demands are sky-high. Without high-carb fueling, riders would lose their 24/7 battle to stay in calorie balance.

“It’s very difficult to ingest enough calories before and after the race to cover daily needs,” Martins said. “Eating more on the bike helps with that, which also improves day-to-day recovery.”

The high-carb conclusion?

Training volume and fueling requirements exist on the same sliding scale.

If you’re training 30 hours a week, crush ‘dem Rice Krispies Treats. Even short-term energy deficiencies can spark symptoms of overtraining and RED-S.

If you’re not training and racing like a pro, apply caution before you fuel like one.

3: The carb-guzzling gene

Athletes who thrive on high-carb fueling have been blessed with a mysterious “carb-guzzling gene.” Because even after a bout of gut training, the body’s capacity to oxidise – i.e., make use of – carbohydrate is a product of nature as much as of nurture.

“Yes, 120 grams is seen as the benchmark, and it gets a lot of talk. But not every rider can tolerate that, and maybe not oxidise it, either,” Visma-Lease a Bike nutritionist Martins told Velo.

As Martins says, not everything that goes in the gut [and doesn’t get spewed back out] goes to good use.

Even more annoyingly, there are few clear indicators of what makes someone a “good” oxidiser. Podlogar said his research has found no correlation between either body size or power output on carb utilisation rate.

Beyond that, the complex relationship between the burn of exogenous (i.e., eaten) and endogenous (i.e. muscle glycogen) carbohydrates means eating more isn’t necessarily “efficient.”

“Genetics seem to play a big role,” Podlogar said when discussing an athlete’s ability to ingest and process carbs.

“The whole picture is quite complex, so accurate measurements can only be made in laboratory conditions.”

Jones revealed after Unbound that he discovered he “needed” 200 grams per hour after he found himself bonking while training with an already ridiculous 150g hourly guzzle.

Surprisingly, even within $50 million WorldTour super teams, only a few lucky leaders are sent for the high-cost “carbox” tests Podlogar refers to.

“We have already performed these tests on some cyclists and found that their abilities vary considerably,” Podlogar told Sportal. “Carbohydrate intake can range from 100 to 180 grams per hour among World Tour riders.”

As Podlogar said, there can be a huge range in riders’ capacity to make use of the fuel they eat.

So, just because the likes of Stornes and Jones can make good use of a stupid amount of sugars, don’t go thinking that you need to go carb-crazy, too.

The high-carb conclusion?

Some riders just can’t go super high-carb. Either their stomach won’t tolerate it and they’ll spend their ride time in a roadside bush, or they’ll keep it down but not put it to use.

And sorry to say it, but the best way to find how high you can go might be a stomach-churning trial and error.

But: Also consider pro-level carb loading

The carbohydrate revolution gobbled headlines in the past few years.

But don’t think performance fueling is all carb drinks and gels.

Podlogar highlighted how an effective pre-race carb load can sometimes lead to confusingly low carbohydrate counts.

“In extremely long events such as Milan-San Remo, energy intake during the race is extremely important. The needs are enormous. In this case, optimizing feeding during the race is crucial as glycogen stores are depleted by the end,” Podlogar said in comments that are equally applicable to the nine-hour sufferfests of Ironman and Unbound.

“On the other hand, in shorter, four-hour races, intake during the race is not so crucial,” he continued. “Here, it’s much more important that riders have well-filled glycogen stores before the start.”

At all levels of performance, “real food” takes priority over the nutrient wastelands of sport nutrition.

Intakes during lower-intensity grand tour stages or maybe a “sprinter’s classic” remain moderate to leave calorie “budget” for the multi-color mountains served by 5-star team chefs.

“[That] allows them to still have a proper dinner after the stage to replenish glycogen stores for the next day,” Podlogar said.

It’s important to note here that such a contorted consideration of calories is for pro athletes only. Don’t skip a gel so you feel free to pile on the potatoes at dinner, or vice versa.

If in doubt, eat all the carbs.

The high-carb conclusion?

If you’re ever surprised by “low” fueling figures in the pro peloton, don’t forget riders probably waddled onto the bike off of a seven-course dinner and a 1,400-calorie breakfast.

Any on-bike fueling plan should be considered alongside the carb load.

“Loading” protocols vary, but the weight of evidence suggests around 8-12 carbohydrate per kilo body mass in the 48 hours ahead of an endurance adventure should be sufficient.