Larger breasts help female cyclists ride faster: unusual scandal erupts at the Tour de France

An unusual dispute has erupted at the women’s edition of the Tour de France Femmes. Several teams suspected their rivals of using sports bras with additional inserts that could not only increase breast volume but also improve aerodynamics during time trials.

The complaints focused on so-called “chest fairings” — soft inserts hidden beneath the racing kit that alter the body’s shape and smooth the airflow. A study published in 2024 in the Journal of Wind Engineering and Industrial Aerodynamics found that such a modification could reduce aerodynamic drag by approximately 3.6% and provide an advantage of up to 0.78 seconds per kilometre. Over a 20-kilometre time trial, this could produce a gain of more than 15 seconds — often enough to separate the winner from the other podium finishers.

The use of such devices is already prohibited under the rules of the Union Cycliste Internationale (UCI). The regulations ban clothing and additional elements that artificially alter an athlete’s body shape for an aerodynamic advantage. Following complaints from several teams, the UCI announced that commissaires would pay particular attention to equipment checks before the individual time trial, including sports bras and other items of clothing.

It is important to note, however, that no disqualifications or officially confirmed cases of violations have been reported so far. The scandal is based on rivals’ suspicions and discussion of a possible loophole in the rules, although scientific studies do confirm that this type of “fairing” can provide a measurable advantage.