What is carbon monoxide rebreathing and why is cycling trying to ban it?

After it was established last year, some cycling teams were using carbon monoxide rebreathing equipment to measure the hemoglobin levels in their riders’ blood before and after altitude training. Cycling’s world body, the UCI, is expected to vote on a ban on it this week.

Although it is not specifically stated in the rules, it is still disputed whether it can be used to improve performance when repeated use is possible, or if it is simply too dangerous to measure performance in a deadly gas.

So far, so bannable, it seems. Given that the UCI is supposed to permit it in a “medical setting,” there is growing uncertainty in the sport about what a ban will actually mean.

A small amount of carbon monoxide, a deadly gas released during the burning of any material, is used to measure the amount of hemoglobin in the blood during the process known as carbon monoxide rebreathing in endurance sports.

Typically, this is done both before and after altitude training.

Red blood cells, which circulate oxygen throughout the body, contain a protein called hemoglobin. More oxygen can be transported to the muscles, increasing the athlete’s resistance to lactic acid burn, enabling them to move more quickly and for longer.

The athlete uses an integrated rebreathing circuit and is connected to an external supply of oxygen and carbon monoxide.

If some of the riders and teams involved weren’t the biggest in the sport, Tadej Pogacar, his UAE Team Emirates-XRG squad, and his closest competitor Jonas Vingegaard of Visma Lease A Bike, wouldn’t likely be so prevalent.

The device’s creator, who is currently in charge of the team, acknowledges that improving performance might be possible, albeit not immediately.

“When you inhale carbon monoxide you reduce]the] oxygen content of blood, so all of a sudden the body]behaves] as if you are at high altitude”, says Carsten Lundby co-founder of rebreathing equipment manufacturer Detalo Health.

It’s like being exposed to high altitude for a few hours if you inhale it once, which will not affect your performance.

This is not what our device was intended for, says Lundby, a professor at the Norwegian University of Lillehammer. “If you inhale carbon monoxide four or five times a day, you will get more haemoglobin,” he adds.

” And due to real-time surveillance of each machine, we can easily identify whether our devices would be misused. “

The UCI does not necessarily intend to ban cheating altogether. The practice still has the potential to be used in a “medical setting,” according to the lawsuit that it is seeking the ruling on safety grounds.

But Lundby and teams are confused.

“At first, I was relieved to see the UCI taking a stand, but the language that says these procedures must be performed in a medical setting threw me off guard. I’m not aware of any medical settings where this has been done, “says Lundby.

Chris Froome’s Israel-Premier Tech is one of the teams that has purchased a device and used it by Lundby himself.

” Israel-Premier Tech’s sole use is for testing purposes to measure the impact of altitude training, “they say.

And it was “nothing new, a method used for decades to measure the effects of altitude training,” according to Visma Lease a Bike.

So, if you can enhance performance, can it be traced? In theory, any change on blood values would be identified by an athlete’s biological passport.

The World Anti-Doping Agency (Wada) is looking into the situation, telling BBC Sport there is some uncertainty about whether a lack of research would lead to a misusing the process.

” Exposure to carbon monoxide (CO) has been discussed by Wada on several occasions, “a representative said”. No conclusive evidence exists yet that CO can improve performance, and there isn’t currently enough data to support that.

Wada is currently looking into the effects of using this CO rebreathing technique frequently and frequently to artificially increase oxygen uptake, transport, or delivery.

Many people believe that the cycling media has caused a stir and that the UCI is merely demonstrating proactivity.

The UCI is expected to announce any decision on 1 February, following president David Lappartient’s formal request to the executive body, at a meeting in France.

Teams say they are willing to collaborate with the UCI on any decision, but it’s not known when Wada will be able to determine whether any additional steps will be taken.