Fake bra size aero gains row prompts UCI to carry out extra clothing checks before Tour de France Femmes time trial

The UCI has warned that extra clothing checks will be conducted ahead of Tuesday’s time trial at the Tour de France Femmes, after concerns were raised that some riders were using extra padding in their bras to artificially enhance their chest size and improve their aerodynamics.

The issue was first raised on Sunday by Wielerflits, who reported that a number of leading teams have complained that riders are using extra bra padding to alter their body shape with the aim of saving watts.

The Dutch cycling outlet also pointed out that some riders appear to have a larger chest size during time trials compared to road races, an issue that has prompted teams to urge the UCI to clamp down on the use of “non-essential” clothing equipment that changes a rider’s body shape.

Increasing volume around the chest has been found to produce a significant aerodynamic advantage for both men and women, redirecting airflow around the body. According to a 2024 study, the largest chest fairings can lead to a 3.6 per cent reduction in drag, saving the rider at least 0.78 seconds per kilometre – the difference between winning and losing a time trial, where aerodynamics is crucial.

Placing items down the front of jerseys to artificially modify chest shape is banned by the UCI. According to articles 1.3.032 and 1.3.033 of the governing body’s regulations, clothing must not artificially alter the rider’s body shape, while using textured fabrics or attaching foam, padding, tape, or plastic to or under the chest to create a more streamlined shape is not permitted.

“Clothing and other items or accessories worn by a rider (including but not limited to helmets, glasses, shoes, or in-race communication devices) may not modify the morphology of the rider,” the rules state.

“Moreover, any non-essential element or device which is added on (or under) or integrated in any clothing, or other item or accessory worn by a rider shall be forbidden.

“A non-essential element shall be any element which does not have a purpose which is exclusively of clothing or protection, or which is not strictly necessary for the functionality of the clothing, or other item or accessory. This shall also apply regarding any material or substance applied onto the skin or clothing and which is not itself an item of clothing or another item or accessory worn by a rider.”

Any rider found to be using “non-essential” clothing faces disqualification and a potential fine of 50 to 200 Swiss Francs (between £46 and £184).

> Confusion as Jan-Willem van Schip disqualified for third time in a year after putting bottle under jersey – but UCI jury claims ejection was due to ‘non-compliant clothing’

Some riders and teams, however, try to get around this rule by placing race radios or bottles down the front of their jerseys. In June, Dutch rider Jan-Willem van Schip – notorious for his boundary-pushing approach to aero gains and the UCI’s rules – was thrown off the Ronde de l’Oise for racing with a hydration pack attached to his chest.

However, when it comes to the women’s peloton – where breast sizes naturally vary – policing the use of non-compliant clothing, particularly padded bras, can prove difficult.

Speaking to the Athletic this week, Koen de Kort, Lidl Trek’s head of technical and innovation, said that the team had noticed the differences between padded bras and sport bras when it came to aero gains, but had not take advantage of them in races.

“The problem is how are you going to police it?” De Kort asked.

“That’s the biggest issue. You can say it’s not allowed [but] how can you say how much a woman needs? That’s time to get pretty much into a grey area of what you’re allowed to check.”

Despite De Kort’s grey area concerns, the controversy surrounding the use of padded bras sparked the UCI into action, the governing body taking the unusual step of warning that extra clothing checks will be carried out ahead of stage four’s 21km time trial to Dijon.

According to Weilerflits, the extra checks will be conducted by a female member of the race jury.

“Riders must be to the final checks before the race (bikes and outfit) no later than 10 minutes before their respective start time,” the Tour de France Femmes communiqué read on Monday night.

“Particular attention will be paid to compliance with article 1.3.032 of the UCI regulations, including nonessential elements and clothing or other items/accessories worn by a rider (including but not limited to helmets, glasses, shoes or in-race communication devices) which could modify riders’ morphology.”