UCI Proposes Ban on Carbon Monoxide Use

The Union Cycliste Internationale (UCI) is set to discuss a ban on the controversial carbon monoxide rebreathing technique used by some cyclists during its management committee meeting in France on January 31 and February 1, 2025. The method, which has gained attention following its reported use by multiple teams during the Tour de France, has raised health concerns due to potential side effects such as headaches, fatigue, and even loss of consciousness when inhaled repeatedly outside medical supervision. While the technique can assist in measuring hemoglobin mass and optimizing altitude training, UCI officials emphasize the lack of knowledge regarding its long-term effects. The proposed ban reflects a growing trend in cycling to address performance-enhancing practices amid health concerns. Notably, the UCI clarified that medical use of carbon monoxide under qualified supervision would still be permitted. This initiative follows prior steps taken by the UCI to regulate performance-enhancing methods in the sport.