The Tour de France is again embroiled in a debate over what cyclists put in their bodies after Dutch team Jumbo acknowledged it was using a dietary aid believed to boost stamina.
The team responded to questions from Dutch newspaper De Telegraaf by saying it was using drinks based on a substance called ketones, which occur naturally in the body.
Team Jumbo manager Richard Plugge said the use of ketones is nothing unusual and is widespread among Tour de France riders.
‘Food supplement’
“It’s a food supplement, like vitamins,” he told De Telegraaf .
Ketones are “supplementary fuel for the muscles”, said Jean-Jacques Menuet, the doctor for a rival team, Arkea-Samsic. Jumbo won four of the first 11 stages on this year’s Tour.
On Tuesday, Ineos team principal Dave Brailsford described Jumbo as “the most improved team over the past three years.” Brailsford, who has masterminded six Tour de France wins, said Jumbo had an “open-minded and expansive approach”.
Ketones are produced by the liver during intense dieting, but a laboratory version is now cheaply and easily available.
Ketones are classified as a food supplement rather than a drug and are not on the WADA’s list of doping products. Two of three WADA criteria would have to be met before they are added — namely, if it enhances, or potentially enhances, performance, if it violates the spirit of sport or if it is an actual or potential health risk.
For the moment, ketones do not appear to be harmful.
“They naturally occur when the liver turns lipids (fats) into glucid (sugar),” Menuet, the Arkea-Samsic team doctor, told AFP .
Artificial ketones, first created in laboratory conditions in Oxford, have the same effect. “At first it cost thousands of Euros for one bottle, but now you can get a bottle on the internet for between €30 and €90,” Menuet said.
