In an exclusive and also rather worrying story, Escape Collective reveals that at least three teams, including the Visma | Lease a Bike, UAE Team Emirates and Israel - Premier Tech have access to an expensive device called a carbon monoxide rebreather, which allows for the precise dosing of carbon monoxide into the lungs. But it may have another use. To cheat doping.
An agressive approach called carbon monoxide inhalation steps into the scientifically new and much riskier realm of inhaling the lightly poisonous gas (carbon monoxide) for the express purpose of performance enhancement. A growing body of recent scientific research suggests CO inhalation can have a powerful impact on measures of aerobic capacity like VO2max, or maximal oxygen uptake.
The technique is not banned by WADA, although it appears to conflict with the agency’s rules around artificial manipulation of the blood. Currently, there is no hard evidence that any WorldTeams are using CO inhalation for performance gains. However it doesn't take long for conspiracies about the practice already being used for a long time now.
Mathieu Heijboer, head of performance for Visma, told Escape that "We have been working with Bent Rønnestad for a few years now to do measurement at the beginning and end of altitude camps." Rønnestad is a professor at Inland Norway University and an expert on altitude physiology; Heijboer emphasised the testing takes place only when Rønnestad is present; he does not stay for the full camp.
"Israel - Premier Tech’s sole use of the Detalo Blood Volume Analyzer is for testing purposes to measure the impact of altitude training," said a team spokesperson in an e-mailed reply to Escape‘s request for comment.
In a brief statement provided to Escape, UAE’s medical director Adriano Rotunno confirmed that the team also uses CO rebreathing for testing purposes. "It’s not a therapy; it’s a diagnostic tool that we use to essentially work out what our athletes’ physiology is," he said, adding that there is no performance enhancement to the measurement method.
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Ondrej ZhasilCycling Journalist
Ondřej Zhasil is a cycling journalist at CyclingUpToDate and has been part of the team since 2023. He is based in Ostrava, the third-largest city in the Czech Republic, and covers professional cycling across the main UCI competitions, including the Tour de France, the Giro d’Italia, and La Vuelta a España. A key focus of his work is startlist analysis and pre-race coverage, where he examines team selections, rider line-ups, and tactical scenarios ahead of major events.
Alongside WorldTour coverage, Ondřej has developed specific expertise in junior cycling and in racing across East Asia, including competitions in China and Japan. He also maintains a broad working knowledge of other disciplines and levels, including cyclocross, while continuing to expand his understanding of mountain bike racing.
Ondřej holds a bachelor’s degree in Mathematics and Physics, which supports his analytical, data-driven approach to performance and race analysis. In his reporting, he regularly uses ProCyclingStats for results, statistics, and historical context. He places strong emphasis on careful sourcing, editorial accuracy, and updating articles promptly when new, verified information becomes available.
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- It’s off-season mate, I’m bored and fed up with the mediocrity of people unwilling to provoke change when they admit things aren’t right. What have you done lately to make anyone realise you won’t put up with things? What conversation, are you dictating to me which part of the incident I have to be interested in or telling me other parts are taboo? That’s what I guess the UCI would really like, let them moan, let it blow over for them pass on to the next thing, let’s keep the status quo, let’s try our best not reviewing or revealing anything about decision-making just like every time before, they’re used to it by now so we can take the risk they’ll never give us grief.Jumpyjohn09-11-2026
- As far as CUTD headlines go this is far from the worst. It helps if you look at it twice and realise it’s a list of descriptions from distinct events. You can’t deny the reality of being a rival if you consider the picture immediately below, frontrunner is unfortunate but I’m guessing this time it’s more a linguistic failure than a clickbaiting opportunity. Just a reminder that this is not an anglo website, for those who find it too tedious to interpret text to get the gist of things which are rarely of great importance (as opposed to eg purposely biaised DOJ extradition translations in order to achieve hidden agendas), there are plenty of anglo cycling websites google can suggest.Jumpyjohn09-11-2026
- Ah, finally someone willing to be a bit proactive.Jumpyjohn09-11-2026
- So? Do you understand the way instructions, decisions and authority work? Do you think in a football match if after a match (or even after play has gone on) a player tells the referee he did touch the ball with his hands when the referee didn’t award opponents a penalty that they will revise the score or force a replay? You really don’t get my point, it’s not against the rider but everyone here is so emotional for her they can’t get back to an issue which needs resolving for the future and the first step (or maybe second) is to try to understand how and why it happens, none of you have contributed in the least to that. All everyone is interested in is letting everyone know they agree how unjust it was, not even sure anyone thinks that could affect anything.Jumpyjohn09-11-2026
- Shouldn’t you be in MOUrning?Jumpyjohn09-11-2026
- Maybe you don’t like it and that’s fine, we all have different sensibilities and topics that touch us, but as you try to show me, it doesn’t hurt to reflect and compare ourselves to others behaving similarly. What precisely is the difference between a sports fan interested in every detail of his/her hero’s life and a celeb fan having the same hobby? It’s far more interesting to learn and think about how and why (which) people do things than reading about what they are actually doing. And just to add another level, maybe you’ll agree we don’t use the same value system for everyone, we discriminate in an enormous number of systematic ways. For example, when is the last time you saw a discussion arguing about the achievements of two politicians to compare or for that matter two business leaders apart from the comparison of hypothetical wealth accumulated? Perhaps you misunderstood the intention?Jumpyjohn09-11-2026
- I don’t think I know what’s beneath the surface but I am willing to think about it, discuss it, compare it to a known past, extrapolate to a potential future and ask/try to find out truth or even take action within my powers (boycotting something or someone is within EVERY person’s reach). If you think your attitude has more chance of changing a result, a process, a system or an institution or it just makes you feel good, keep at it but to me it looks like you’ve already given up before trying.Jumpyjohn09-11-2026
- All journalists should start asking the UCI uncomfortable questions, sending inquiries about the interpretation of the rules and the justification of the results. This is the only way to change anything.averagecyclist09-11-2026
- OFF TOPIC: OK, don't get mad with me... I have some very important news, something that can't be overlooked, something that can't be ignored!!! In the new documentary Anatomy of a G.O.A.T. (released in November 2026), legendary Belgian cyclist EDDY MERCKX spoke about TADEJ POGAČAR: Merckx: “He has revived a style of cycling that we had almost forgotten. He is now better than me.” Key statements by Merckx about Pogačar in 2026: - Acknowledging his superiority: This time, Merckx openly admitted, without any subsequent backtracking or reservations, that Pogačar had surpassed him and was now above him. This contrasts with 2024, when he quickly softened his remarks about Pogačar being faster. - The possibility of a historic triple (Giro, Tour and Vuelta): During the July Tour de France (where Pogi claimed his fifth title), Merckx stated that Pogi was the only cyclist in history capable of winning all three Grand Tours (the Giro d'Italia, Tour de France and Vuelta a España) in a single season, provided the conditions were right and he had sufficient team support. - Lack of serious competition: Merckx emphasised that Pogačar has no real rivals in the mountains since 2024, thanks to his extraordinary climbing ability and the fact that he continues to improve despite still being under 28 (he turned 28 in autumn 2026). - Praise for his racing style: Merckx highlighted how Pogačar is bringing back the aggressive, uncompromising spirit of cycling's golden era, when races were not merely about calculated stages and tactical conservatism, but about attacking from long distances. PS: Now, this is real important cycling news. This is not "boring" ... this is called making real history, not BS history. Capish?PogiSloFans09-11-2026
- how else is there to look at things? we are responding to words and pictures, we are not there. your long winded replies make zero sense to anyone. pretty much everyone but you says the same thing. MS was robbed. somehow you think you're so smart to dig beneath the surface and discover something no one else, including the opposing coach and cyclist, saw. lol. you are a tool.mij09-11-2026
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