What are the mysterious blue cartons Visma-Lease a Bike are drinking from at the Tour de France?

Matteo Jorgenson grinds to a halt after his Tour de France time trial and parks up along the barriers in Caen. Exhausted and gasping with thirst, he reaches for a bottle from his soigneur, and sips at its contents. He’s then passed a blue carton, its cap already unscrewed, and, in a gulp, necks all of the liquid inside. When Jonas Vingegaard arrives shortly afterwards, the ritual is repeated again.

You might have spotted the blue cartons on the television. Visma-Lease a Bike aren’t the only ones drinking from them – EF Education-Easypost are too – while other teams' riders swig dark red liquid from plastic bottles beyond the finish line.

So what are they drinking? What’s the mystery fluid? The answer isn’t as scientific as you might think: it’s cherry juice.

“They say it’s a good dose of antioxidants,” Jorgenson tells Cycling Weekly. “We’ve been using it for years – the team’s been using it for a long time, even before I joined. I think it works well.”

The blue cartons of Visma and EF come courtesy of nutrition brand Amacx, and contain a recovery product with sour cherry extract, a substance rich in anthocyanins, which help stave off body cell damage.

According to EF’s team doctor, David Hulse, the extract first cropped up in the peloton over a decade ago, and is now used widely.

How, then, do cherries help? “They contain extremely high concentrations of antioxidants and flavonoids, and have two functions,” Hulse begins. “One is to reduce inflammation, which is an important part of recovery for multi-day stage races. The other is to mop up the free radicals [unstable molecules], which are potentially harmful and can cause further inflammation.”

In the past, Hulse explains, riders might have received a small can of Fanta at a race finish. “The idea was to deliver a high amount of simple sugars to take advantage of that refuelling window,” he says.

“Now, we’re making use of the fuelling window, but the first thing we’re using is a high dose of antioxidants and flavonoids, so we’re starting the recovery process right on the finish line.”

At this year's Tour, EF’s riders have been taking two doses of Amacx cherry juice every day – one immediately after each stage, and another in the evenings.

Other teams have different ways of consuming the substance – UAE Team Emirates-XRG’s Tadej Pogačar, for example, has been drinking a similar product made by Enervit, concentrated into a plastic water bottle.

“It’s really a good product to get down you,” Hulse says. “It’s also very palatable.” Jorgenson concurs: “I like the taste. The taste is good.”

Recovery products can often feel like chemical potions. Sometimes, though, they're as simple as cherry juice.