Bra padding checks aim to prevent major aerodynamic advantage for Tour de France Femmes riders

Tour de France Femmes officials are checking the clothing and equipment of riders in an effort to prevent them from artificially reducing aerodynamic drag and gaining a significant competitive advantage.

Bra padding has been identified as one potential item of interest, with race organisers paying particular attention to 'non-essential elements and clothing... which could change riders' morphology.'

Riders have been subjected to checks in the minutes before their start times and face expulsion and a fine if they're found to be attempting to circumvent the rules.

"Issues have reportedly been raised about padding in bras that could result in riders gaining one second per kilometre," reports BBC Sport.

"Race organiser ASO issued a statement following Dutch media reports of concerns some riders had used bra padding as aerodynamic fairings to improve efficiency.

"Other items have also been known to be inserted into a skinsuit around the chest area to smooth airflow around the body.

"Much attention is paid to airflow and aerodynamic efficiency in cycling as the correct shape of bike frame and skinsuit can save a rider several seconds, especially during a time trial - where a rider races alone against the clock."

Fairings are designed to create a smoother profile of a structure, machine or indeed athlete in order to redirect the flow of air around the mass and reduce air resistance, known as drag.

Chest fairings fall under the International Cycling Union (UCI) ban, which saw male competitor Jan-Willem van Schip thrown out of a race in June for stuffing a water bottle inside the front of his jersey.

"In a study by researchers at universities in Scotland and the Netherlands, a mannequin of a male rider, 177cm in height, inside a wind tunnel found fairings can give rise to 'significant drag aero reductions' and that wider objects yielded the largest gains," reports BBC Sport.

While the insertion of a water bottle is a crystal-clear example of a breach of the rules, the matter of bra padding is complicated by the obvious overlap with a legitimate physical requirement for female athletes.

Swiss rider Marlen Reusser has the yellow jacket after four stages of the Tour de France Femmes, which got underway in Switzerland on Saturday.

Race favourite Demi Vollering (Netherlands), Cedrine Kerbaol (France) and Sigrid Ytterhus Haugset (Norway) all ended stage four within a minute of the general classification leader, who won the stage to edge in front of stage three winner Haugset.

The first two stages were both won by Lorena Wiebes of the Netherlands, who has had the green jacket as the points leader since she crossed the line first in Lausanne on day one and ended the 2025 edition as the points leader.

Vollering finished second behind serial world champion Pauline Ferrand-Prevot of France.

Five remaining stages include two mountain stages as the riders work their way towards the finish line in Nice on August 9.