It probably hasn’t escaped your attention that top riders are consuming huge amounts of carbohydrate mid-ride.
“The amount that we consume is night and day different to when I started my career,” says Team Jayco-AlUla’s domestique Luke Durbridge, who’s been a pro for 16 years.
“I put that down to why the racing is so much faster now. Riders aren’t running out of fuel. When I started, we were looking at little more than 60g carbs an hour. Now, we’re at 120g and more.”
But how are they managing this without the ensuing gastro issues of old?
Tighter ratio
“We’ve known for years that the addition of fructose to glucose increases how much someone can tolerate during exercise,” says exercise physiologist Tim Podlogar, who formerly worked for Red Bull-BORA-hansgrohe but now assists at Tudor Pro Cycling Team.
“But whereas in the past, it was thought a ratio of 2:1 (glucose to fructose) was optimum, the sports-nutrition industry are finally realising that this ratio is more like 1:0.8 or even 1:1 for some. I think that’s helped.”
An explanation is needed. Historically, it was thought that 60g of carbs per hour, in the form of glucose, was the ceiling. Any more and you’d suffer gut irritation.
Then, Professor Asker Jeukendrup discovered that adding fructose to glucose in the ratio of 1g to 2g raised this carbohydrate ceiling from 60g to 90g.
That’s because fructose is transported across the intestine via a different channel to glucose, so there’s no internal sugar ‘traffic jam’ going on.
This idea then evolved, through much lab work and anecdotal feedback on the tighter ratio, which is one reason why 120g became the benchmark to aim for.
But according to recent revelations by former Ineos Grenadiers nutritionist Aitor Viribay Morales, many of the British team’s riders have exceeded that figure, reaching up to 200g in certain parts of races. That’s 800 calories an hour.
This bypassing of 120g is echoed by Podlogar.
“We certainly had riders consuming 150g an hour at Bora. We also had some at 90g an hour,” he says.
“The key is that there are significant differences between riders, for various reasons. One is body size, which we showed in a study last year. In general, the larger athletes could tolerate higher levels than the smaller riders.
“Another reason is that we know there’s significant individual variety in a person’s ability to absorb glucose. It’s a greater difference than in a person’s ability to absorb fructose.
“That’s why, going forward, there could be a personalisation of that ratio. It certainly makes sense from a scientific perspective. How feasible that is from a practical perspective remains to be seen though.”
Personalised plans
This individualisation in fuelling is something Podlogar is currently working on.
As for the practicalities of application, he’s referring to the complication of individual formulations for every rider at, say, the Tour de France.
That would mean different ratios for eight riders over countless water bottles for the soigneur to then hand out at feed zones. Is this a step too far?
“Luckily, the teams are growing richer and more resourceful, so they can position enough of their staff on the sides of the road to deliver the nutrition to the riders,” says Podlogar.
“It’s certainly something that the bigger teams are thinking about months ahead of the races. How many people do we need on each climb? How many bottles? That sort of thing.
“Last year, when I was working for Primož Roglič and we were writing up his plans for the Tour de France and Vuelta a España, we measured things like his sweat rate and how many carbohydrates he could consume, and worked out how many bottles he’d need for each stage and how many people you’d need to hand out the bottles each day.
“Resources are so important to increasing the amount of carbohydrates and number of drinks consumed.”
It's not only at races, either. Modern road cycling places ever-greater importance on training camps, often in the WorldTour hotspots of Sierra Nevada, Andorra and Tenerife. There, instead of riders heading out from home unsupported, they have staff to keep them grazing.
“It’s difficult to consume 120g of carbohydrates per hour when you’re training solo. You’d have to keep stopping at service stations to refuel,” says Durbridge.
“But when you’re on a camp and have a car shadowing you all the way, you can constantly top up. This has made heavier feeding possible.”
“This is one reason why amateur riders would find it hard to fuel high like the professionals,” Podlogar adds.
They just wouldn’t be able to carry enough fuel. “Unless you rode with a bar bag, of course,” he says. “But many don’t need that much or won’t be able to tolerate that amount.”
Training your gut
“We don’t actually term it a high-carbohydrate session, but we often aim for around 120g an hour during high-intensity sessions,” says Podlogar.
“It’s not fuelling for the sake of fuelling but to maintain the quality of the session. It’s particularly useful for older pros who might have grown up with the idea that lower fuelling made you a mentally and physically stronger rider. We know that not to be true.”
Durbridge agrees that high-carb sessions are intensity-specific rather than solely aimed at training your gut.
There are other ways to get your body used to dealing with this constant digestion of carbs.
During his time consulting with Visma-Lease a Bike (he’s now director of sport strategy at Bora-hansgrohe), I spoke to Jeukendrup about high-carb feeding and he said that cyclists could learn from competitive eaters, who employ various tactics to raise their capacity.
For the active individual, that meant training with relatively large volumes of fluid and immediately after a meal.
Both are methods to reduce bloating during exercise and, ultimately, to increase the capacity to absorb carbohydrates, albeit evidence to support this is more anecdotal than empirical.
What’s the impact of this greater tolerance? If you can stomach it, Podlogar says you shouldn’t expect to see an increase in power output; instead, it’s all about making you more fatigue resistant.
So, instead of seeing a performance drop after two hours, you’ll sustain your efforts for an overall faster ride.
Everyone’s different
In theory, it’s a simple equation – eat more and reach the finish line quicker. But like most things in exercise science, it’s never quite that straightforward.
There are several scenarios where your carb ceiling should be lowered, or you’ll have gastro distress.
“We know that the utilisation of ingested carbohydrates during exercising in the heat drops. That’s been known for some while,” says Podlogar.
“We used to think it was absorption of sugars from the intestine that was the limiting factor.
“But we have some data coming up later in the year showing that it’s not [gut] absorption, rather it’s that the muscle can’t take in the same amount of glucose. You’re probably looking at around 20% less in the heat.”
“Tied in with the heat, you should also maintain good hydration levels,” Podlogar adds.
“Studies show that your carbohydrate intake goes down if dehydrated. This is another reason why high resources in the best-funded teams pays off – drinking many bottles isn’t just good for preventing dehydration, but helping to absorb and assimilate carbs too.”
You should also ensure you're aware of how much energy you’re consuming when digging deep.
“We know that when you exercise above threshold, absorption is limited because the blood is heavily split between the exercising muscle and the skin for cooling purposes,” says Podlogar.
“That can reduce carbohydrate absorption by as much as 50%. It’s an interesting conundrum from a nutritionist’s perspective, because on one hand you might think that you should fuel less on the climbs.
"But an ascent is always followed by a descent where the intensity drops significantly.
“If you’re not pedalling at all, you can absorb high levels of carbs. This is where a strong, well-trained gut comes in. The WorldTour riders can fuel on the climbs so the carbs are already in their stomachs and intestines.
“These must sit comfortably and unabsorbed on the way up, and then be fully absorbed on the downhill. That’s where those high-intensity sessions come in.”
Podlogar says this is a risky strategy for the amateur rider, especially if they’re inexperienced. For now, focus on simply consuming, say, an extra 10g of carbohydrates per hour on the flat and seeing how your stomach responds.
If it doesn’t gurgle and growl, try a little more.
How you consume these carbs isn’t overly important, says Podlogar, whether it’s from energy drinks, gels or bars. Blocks and jellies are popular at the moment.
“They behave exactly the same way as each other because they all contain zero fat and zero fibre,” he adds.
“As a sidenote, rice cakes are becoming less popular in the professional peloton these days. You won’t see them used by the best riders anymore, at least on super-hard days.”
Carb conclusion
Where does all this leave the carbohydrate ceiling? Will you tip over 200g?
As a recreational rider, arguably not. You’re not racking up enough miles – around 30,000km a year for most male WorldTour professionals – to acclimatise to burning and consuming so many calories.
Also, races such as the Tour de France, where the pros are riding for three weeks, help train the gut to tolerate more.
Consuming 15 to 20g of carbohydrate per kilogram on harder days is a potential adaptive scenario for the body to take in and absorb high amounts of energy (although only if the rider doesn’t start the day in a low-energy state, says Podlogar).
“There will be individuals with super-high intakes because they’re large and powerful, plus they might have high absorption rates,” says Podlogar.
“You might see them commonly taking in 180g an hour if not more.”
That stacks with Morales’ comments that some Ineos riders hit 200g an hour. If they do reach these levels, Podlogar says it’ll be down to individual strategies and ratios based on work in the laboratory and refined on the road.
Achieve all of that and professional cycling will only continue to go higher, faster and longer.
