Teams at the Tour de France Femmes are concerned riders are wearing oversized bras with extra padding to save watts, WielerFlits reported on Sunday evening.
The extra padding can effectively create a 'chest fairing' that offers an aero advantage while riding on a time trial bike.
Due to their potential advantage, chest fairings have been prohibited by the UCI. Article 1.3.033 of the UCI’s rulebook prohibits clothing that modifies a rider’s body and bans “non-essential” equipment.
According to WielerFlits, several women’s WorldTour teams are making an urgent appeal to the UCI to enforce the rules ahead of Tuesday’s stage four of the Tour de France Femmes, a 21km individual time trial through Côte d'Or.
0.78 seconds per kilometre
Although 21km is not a long distance, padding could still have an impact on the result of the race.
A 2024 study published in the Journal of Wind Engineering and Industrial Aerodynamics found the largest chest fairing gives a 3.6% drag reduction and at least 0.78 seconds per kilometre.
It said the time gained through the use of a chest fairing “can decide who wins or loses a time trial”.
The same study said chest fairings have been used in competition, including the 2023 Tour de France individual time trial and 2023 Glasgow Road World Championships ITT.
WielerFlits reported that padded chests have been seen at other women’s races, including the 2024 Paris Olympics time trial and Giro d’Italia Women.
Front pockets banned
The UCI is yet to comment on chest fairings at the Tour de France Femmes. But it recently adjusted its rules to prohibit jerseys with front pockets in light of their potential aerodynamic benefit.
“At the beginning of 2026, the UCI observed that several riders were wearing jerseys featuring front internal pockets containing nutritional products that were generally not consumed because they were extremely difficult – or even impossible in race conditions – to access. These pockets result in significant alterations to the riders’ body shape,” it said in a statement released in June.
“Given the established link between aerodynamic gains, increased speed and the severity of accidents, and considering that the practice also raises issues of sporting fairness, the UCI has decided that jersey pockets must be located exclusively on the rear of the garment.”
BikeRadar has contacted the UCI for comment on chest fairings at the Tour de France Femmes.
