UCI urges WADA to “take a stand” against carbon monoxide inhalation by cyclists


UCI urges WADA to “take a stand” against carbon monoxide inhalation by cyclists

The Union Cycliste Internationale (UCI) is calling on the World Anti-Doping Agency (WADA) to regulate the use of carbon monoxide by the world’s top cyclists, a substance preferred by athletes to drive an increase in EPO, haemoglobin levels and VO2max.

It is currently legal for cyclists to inhale carbon monoxide to simulate altitude training.

Carbon monoxide prevents oxygen molecules from binding with haemoglobin, which normally supplies the body with oxygen. Therefore, the body adjusts to the lack of oxygen and provides the athlete with a surge of Erythropoietin (EPO), simulating altitude training. Carbon monoxide increases total haemoglobin mass which increases endurance.

Despite being legal, the practice is very contentious due to its potentially lethal nature. Repeatedly inhaling the gas has the potential to cause artificial hypoxia. Hypoxia is low levels of oxygen in your body tissues. It causes confusion, restlessness, difficulty breathing and rapid heart rate.

However, several athletes and coaches support the practice and argue that it enables more accurate blood analysis.

UAE Team Emirates’ Tadej Pogacar, 2024 Tour de France champion, and two-time champion Jonas Vingegaard are among those who have used this practice. Chris Froome’s Israel-Premier Tech also used the method. However, all three claim that they used it for testing purposes only.

Three-time Tour de France champion Pogacar said: “It's a device to test how your body reacts to altitude. We blow into a balloon for one minute as part of a test that we have to repeat every two weeks. I only did the first part because the girl who was supposed to supervise the second part never showed up. It's not like we breathe it every day.”

UAE Team Emirates itself said: “Carbon monoxide rebreathing is a method to assess total haemoglobin mass and has been used in altitude training and research for over 20 years. It is a well-established, safe, professional method that is backed by a very large amount of research.”

Carsten Lundby, Professor of Integrative Exercise Physiology at the University of Southern Denmark and Chief Executive of Detalo, which produces the rebreathing device referred to above, says that the rebreathing test raises carbon monoxide levels in the blood to just under 6%. Normally, levels are around 0.5%. Those that smoke could have levels around 8%.

Lundby says that levels decrease to 2% by the morning after the test, and resume to normal within the day. Therefore, she highlights that it is a safe practice.

However, the UCI has voiced its reservations. It agrees that the practice may be acceptable in “controlled medical environments,” but is certainly not as optimistic as Lundby. The UCI stated: “[We] clearly ask teams and riders not to resort to repeated CO inhalation. Only the medical use of a single inhalation of CO in a controlled medical environment could be acceptable. The UCI also formally requests that WADA take a position on the use of this method by athletes.”

The Movement for Credible Cycling (MPCC) which consists of eight world teams and 385 athletes is strictly against the practice: “Considering the health risks (potentially fatal), the technically complex and artificial aspects (misuse of technical and therapeutic means to artificially create physiological changes), and the current World Anti-Doping Code, the MPCC can only strongly discourage the use of this technique... until it is banned.”

Exercise physiologist Dr Jamie Pringle argues that banning the practice is “inevitable” considering former decisions: “Gases like xenon and argon, which are used for the exact same purposes of reducing the oxygen-binding to haemoglobin and stimulating erythropoiesis, were banned by WADA 10 years ago.”

WADA is investigating, and a final verdict is expected within the coming months.

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