At least four riders - Thomas De Gendt, Jelle Vanendert, Victor Campenaerts, and Jens Keukeleire - were spotted with small white dots on their legs during the 35km stage three, in which they finished third behind Team Sky and BMC Racing, with team staff explaining that it was a special gel designed to improve aerodynamics.
"It's an aerodynamic gel", team doctor Servaas Bingé told Sporza. "It's Speed Gel. The gel reduces air resistance."
"The higher your speed, the more profit you can get from aerodynamics, all small bits help and we try to support our riders in any way, so the speed gel provides an aerodynamic advantage and perhaps also a mental advantage."
However questions have been asked about whether this gel could contravene UCI rules which state that “it is forbidden to wear non-essential items of clothing or items designed to influence the performances of a rider such as reducing air resistance or modifying the body of the rider."
UCI jury president at the Critérium du Dauphiné, Jean-Michel Voets told Het Nieuwsblad (opens in new tab) that the technical committee would examine the gel's use, but that no decision would be made until after the race.
"Whether that is legal or not, I cannot say anything about it at all," Voets said. "I reported it to [UCI Manager of Equipment] Jean-Christophe Péraud. It is better we make a judgement after the Dauphiné about this to see what should be done in the Tour."
Team Sky raised eyebrows too in the 2017 Tour de France when it departed from Düsseldorf with its vortex skin suits. The Castelli TT Suit 4.0 featured patches with patterned nodes on the sleeves to enhance airflow. Despite the controversy and complaints from teams including FDJ, they continued to use them.
"You know that all of this adds up and it's a marginal gain," Team Sky's sports director, Nicolas Portal said last July. "All the teams have those little things that makes them X faster over 100 kilometres when testing.
The 2018 Tour de France features a team time trial of the same distance for stage three and for stage 20 in Espelette, an individual one of 31 kilometres.
However Bingé, using one of cycling's famous phrases, said the attention is unwarranted, "You cannot make a racehorse out of a donkey, and that line applies in all circumstances."
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