Cycling is so full of mind-boggling jargon that it almost threatens to spoil the fun at times. If it’s not the complications of power measurement, it’s the physiology of the fuel or the PhD-level physics behind the aerodynamics that fools the wind. The latest word to bring us into the limelight is ketones, described by some as a groundbreaking legal performance-enhancing supplement. More and more WorldTour teams are announcing partnerships with mystery drink providers that are becoming hard to ignore. But what exactly are ketones and do they really live up to all the hype?
This much is clear: ketones have become ubiquitous among professionals, as I found out for myself at Paris-Nice in March. At several stages, as riders crossed the finish line, they grabbed coats, Haribo and, in some cases, ketones from waiting owners before returning to their team buses.
Soudal Quick-Step was one of many teams seen using the drink and was active on social media during the race sharing videos of Remco Evenepoel’s sponsor KetoneAid products after the stage. As I witnessed this new phenomenon, a multitude of thoughts crossed my mind. Do riders who use these products really believe in their effectiveness and, on the other hand, do they consider those who don’t use them to be worthless?
A quick internet search revealed that DeltaG, the ketones used by Mathieu van der Poel’s Alpecin-Deceuninck team, was developed at Oxford University, just down the road from where I live. A few emails later, and I was on my way to meet the scientists over drinks. I wanted to break down the wall of secrecy surrounding ketones to find out what the hype is really about.
Visma-Lease a Bike were early adopters of the supplement
(Image credit: Getty Images)
Alternative fuel source
First, what are ketones? In short, they are a fuel produced naturally in the liver when the body breaks down fats, providing an alternative fuel source when glucose availability is limited, such as during long journeys. “There is no human body that doesn’t have ketones present,” says Professor Kieran Clarke of the University of Oxford, a ketone researcher and the brains behind DeltaG, one of several brands of ketones used in cycling today. “Fat breaks down into ketones,” she explains, “which are very similar to glucose. [molecules] and work in similar ways.”
The ketones used in supplements are ketone esters, a synthetic compound consisting of a ketone group linked to an ester group. In theory, by taking these exogenous ketones, in drink form, athletes are providing themselves with an additional source of fuel alongside their glucose stores to ensure they can go the distance in long, hard events. However, the Movement for Credible Cycling (MPCC), which includes Groupama-FDJ, Confidis and Bora-Hansgrohe, among others, prohibits its member teams from using exogenous ketones. Given that ketones are produced naturally, why the skepticism? “The UCI says it is investigating the long-term health effects of ketone use,” says MPCC chairman Roger Legeay. Cycling Weekly. “We want to wait to see the results of the investigation.”
Hold your nose: The taste test
In a social media clip after Flèche Wallonne recently, Soudal Quick-Step’s Ilan van Wilder was pictured holding his nose drinking a bottle of KetoneAid at the finish line. Having recently tried ketones for myself, I understood why – the taste is terrible.
Trying ketones to monitor their effect on my performance, I was immediately put off by what can only be described as a bitter, metallic taste. The DeltaG product I tried was listed as blueberry scented, but it was enough to put you off for life.
Javier Gonzalez believes that the bad taste is part of what has created questions about the legitimacy of ketones. “Bad taste adds to the mystique surrounding ketones. People think, ‘Oh, this tastes awful, it must be doing something really powerful’ so I think that’s probably partly the case.
The MPCC’s stance is not surprising, especially since the first inclusion of ketones in cycling caused such high-profile controversy. This was at the time of the 2012 London Olympics, when it was not yet known whether the substance could violate anti-doping laws. A report in the Mail on Sunday in 2020 revealed that DeltaG was secretly tested by some of Great Britain’s top managers in the build-up to the games in a testing program sanctioned by UK Sport. According to Sporting Intelligence, the product was not medically approved at the time, and yet 91 guinea pig athletes from a variety of sports signed nondisclosure agreements stating that if they became ill from using the product, they would not discuss what they had been. dealing with those outside the program. The Mail on Sunday report stated that, if revealed, the plan was to portray the scheme as simply GB ahead of the curve in terms of the development of marginal gains.
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Research on ketones has progressed significantly since then, and they are not currently banned by the UCI, the World Anti-Doping Agency (WADA) or the International Olympic Committee. [IOC]. Clarke tells me that exogenous ketones were first produced at Oxford University at the request of the US Department of Defense. The US military’s hope was that ketones would give troops an extra edge and help them stay fueled longer when operating on low rations behind enemy lines and during combat.
View of Visma
In cycling, ketones are no longer primarily considered a fueling product, but rather a recovery aid, as Martijn Redegeld, head of nutrition at Jonas Vingegaard’s Visma-Lease a Bike team, explains. “I think the whole buzz about ketones started five or six years ago,” he says.
“There were two different reasons for using them, one was more focused on acute performance benefits, meaning riders had to take ketones just before or during a race; the other domain was more focused on recovery goals and adaptive training responses. I think over the last few years, research has shown the most promising effects in that secondary area, on the recovery side.”
Ketones are reported to improve your sleep
(Image credit: Getty Images)
Cycling Weekly contacted other WorldTour teams to discuss the use of ketones, but received no response. Some teams acknowledged their use of ketones but refused to talk about why. Professor Clarke says research is revealing that ketones have the power to enhance cognitive performance as well as providing a physical boost. However, Visma’s Redegeld is still not sure about the cognitive benefits. “This is an area where research is being focused, but to be honest, I think that part is still quite unexplored,” he says. “The evidence so far is anecdotal. What is clear is that ketones are more than just a fuel. At first, it was felt that they were just like carbohydrates, just an extra fuel, but now we know that they can be seen as a signaling molecule that triggers all kinds of other processes in the body.”
Nocturnal Ketones: Sleep Enhancer
(Image credit: Getty Images)
If you can get past the nausea upon consumption, ketones are reported to improve your sleep and get you fast asleep like a pro. Professor Gonzalez explains why: “They appear to have a potential effect on the balance of hormones including norepinephrine,” he explains, “which may have a direct effect on sleep, but ketones may also affect sleep indirectly because they also reduce urine production. So if you have a ketone ester, you don’t need to go to the toilet as much, which can mean you don’t wake up in the night needing the toilet.”
Researchers at universities around the world continue to explore the benefits and side effects of ketones. One drawback is cost: exogenous ketones are so expensive that it can be difficult to get research projects approved. “Some of the ketone studies we’re interested in doing are long-term, supplementing people with them for weeks, but the cost then skyrockets and it’s hard to fund,” says Javier Gonzalez, professor of human metabolism at Bath University. “That’s why we don’t currently have any projects going on for ketones.”
It’s also for cost reasons that Gonzalez believes hobbyists are better off spending their money on other forms of performance enhancement. “I think the cost-benefit ratio [from ketones] it is small”, he says. “Even if they do improve performance, there are probably other, cheaper things that give you more bang for your buck, at least based on what we currently know.”
As an example, DeltaG Ketone Drink is available in boxes of three, with the most expensive retailing at £75 per box.
Believers and skeptics
Redegeld echoes Gonzalez’s view on cost and says that while amateurs could see benefits from using the product, he would recommend making changes elsewhere first. “My advice is always that amateurs start by getting the basics right,” says Visma’s nutritionist. “Just meeting your energy needs, getting good calories and the right amount of carbohydrates, will have a much greater benefit. But I think for an ambitious amateur who does all these things correctly, ketones can certainly be a supplement.”
Like Visma-Lease a Bike, the UAE – the team of two-time Tour champion Tadej Pogačar – are not part of the MPCC so will be able to use ketones freely. Interestingly, then, UAE riders are advised not to use them. Outspoken sports scientist Iñigo San Millán, head of performance at Pogaçari’s team, is not convinced. “We know that the best fuel for muscle contraction during high-performance exercise is glucose and also lactate,” he tells CW. “Ketones are there as supplemental fuel. Yes, supplemental fuel works, but it is leaner and lower quality fuel compared to carbs. That’s why if an athlete asks me if they should have carbs or ketones, it’s always carbs. We always try to educate them and explain why in-race ketones can be harmful.”
Ketones are not banned in the UAE, but San Millán explains to riders that there are better alternatives. What about the supposed recovery benefits? “For a recovery drink or formula, I’ll always stick with carbs and protein, rather than ketones. In my opinion, ketones are a low-grade fuel,” says San Millán.
Contrary to university researchers, it is not budget constraints that are preventing the UAE from using ketones. “Sometimes athletes have asked us, ‘Will the team supply these ketones?’ The answer is no and the reason is because we don’t believe they are necessary,” he explains. “In my humble opinion, there are better ways to be effective with your food.”
With highly qualified scientists like San Millán writing about the effectiveness of ketones, it is difficult to understand the faith placed in them by some teams – especially since they are not willing to discuss their reasoning. Cycling’s murky past means that any new purported performance-enhancing substance is bound to raise doubts. However, amateur riders will have to be very convinced of the benefits of ketones to regularly pay £75 for a drink that offers, at best, a marginal gain.