'Bra-gate' at the Tour de France Femmes: "30 seconds gained over 40 kilometres"

During the 2026 Tour de France Femmes, the individual time trial became the day's biggest talking point. Not only because of the race against the clock, but also because the UCI announced additional checks to ensure riders are not artificially padding their bras. A remarkable news story that comes as no surprise at the Ridley Aero Performance Lab. "We've already seen that this trick can result in up to 30 seconds of time gain over 40 kilometres," says R&D Engineer Daan Teugels. "But that potential gain is highly individual."

The pursuit of marginal gains has led engineers and teams to come up with creative solutions for years. Last year, rumours were already circulating that some female riders were padding their bras to improve their aerodynamics. In the men's peloton, race radios were positioned on the chest for the very same reason for years, until the UCI introduced a ban.

The regulations are still very clear today. In Article 1.3.032, the UCI states that non-essential parts of a rider's outfit that alter the body's natural shape are prohibited. That is why additional checks are being carried out before the time trial, including inspections for padded or push-up bras.

Not the same for every rider

The fact that this measure has now been introduced does not surprise Teugels. At the same time, he is quick to put the possible time gain into perspective. "In time trials, you generally see two typical positions. Either you're very compact, like Remco Evenepoel, or you have longer upper arms and ride in a slightly higher position. In the latter case, there's a gap between the hands and the head. Air flows through that opening underneath the rider's torso, causing the hips to act like a sail."

By partially filling that space, the airflow can become more favourable. However, this does not provide the same benefit for every rider. "The gain depends entirely on the rider's body shape and position on the bike. For some riders, the effect is limited, while for others we've measured gains of up to 30 seconds over a 40-kilometre time trial during our testing."

Not a new principle

The idea of optimising airflow around the body is certainly not new. In triathlon, for example, integrated hydration systems are used to improve aerodynamics. In road cycling, however, such modifications to a rider's body shape are not permitted.

During testing at the Ridley Aero Performance Lab, we found that even simple materials, such as kitchen paper, could already have a measurable effect when used to add volume to the chest area. Naturally, any time gain sounds like music to the ears of every team.

Just look at yellow jersey wearer Sigrid Ytterhus Haugset, who defended her race lead aboard the Ridley Dean Fast during the individual time trial. Every second can make the difference, although it will have to be achieved without any additional tricks.

Also featured in the media

The research conducted by the Ridley Aero Performance Lab was picked up by several Belgian media outlets. VRT NWS produced a radio report on the aerodynamic effects of bra padding during time trials, while VTM NIEUWS visited the Aero Performance Lab for a television report on the so-called "bra-gate". Dutch broadcaster RTL also visited what is widely regarded as the best-known wind tunnel in the Benelux.