The opening weekend of the Tour de France was a frenetic race in many ways. On the bike, the riders did not fail to put on a show, but the biggest battle many of them faced was not between riders, but rather with Mother Nature. As the race started in Florence, a midsummer heat wave hit Italy and turned the country into an oven.

Mark Cavendish, the most high-profile rider, vomited midway through the race and was handed an icy towel by the waiting press at the finish. The 36°C heat did not help either, as it was already shaping up to be a tough day for the British sprinter as he climbed the 3600m to Rimini.

A light breeze on Sunday did little to ease the heat, turning the Adriatic coast into a convection furnace. While the weather may have been perfect for the throngs of revelers who flocked to the nearby seaside towns, fans gathered at the start in Cesenatico, where teams were frantically equipping their riders with cooling items.

Ice vests were a common sight, ice slush drinks were downed, popsicles were plentiful, and nearly every rider started the race with at least one ice sock pulled down over their jersey. Riders stuffed their jerseys with water bottles and took a brief respite from the scorching heat of the race.

To understand the science behind the cooling technology and each team's technique, Cycling News spoke with several teams at the start of the second stage in Cesenatico.

Prior to the race, all teams focused primarily on acclimatization. Heat acclimatization makes a big difference. Speaking to Cycling News before the Tour, Dan Rolland, head of performance at Red Bull-Bohra-Hansgrohe, gave examples of the potential benefits of heat acclimatization.

"Your threshold is 400 watts. In hot conditions, for example, your threshold could drop to 370 watts. Heat acclimatization training can probably bring your threshold back down to 390 or 95, so you can close the gap.

If this is an equipment change, a savings of 20-25 watts is what the team should achieve at great expense, and the benefits of acclimation and subsequent cooling strategies are enormous. It would not be surprising to see teams investing in new technology and staff support in this area.

"It's clear that the world is warming," began Ineos Grenadiers coach Zach Dempster matter-of-factly. [It's well documented how the body reacts to heat, and it's part of the preparation because it positively stimulates training. A lot of athletes have heat chambers at home and they go in there to train.

At Team DSM-Filmenig-Post NL, Narelle Neumann, head of the scientific department, explains that this process begins for athletes three to four weeks before the race.

"Some athletes train on the bike because they don't want any extra stress during training. For other athletes, it is better to do it after recovery so that it does not interfere with their training. For these athletes, we do a sauna session or a warm bath session. The key here is to monitor how much they sweat and to keep them hydrated so that it doesn't affect them the next day."

The preparation phase does not stop until the moment the race begins, and even in the week leading up to the race, with a furnace like Florence's, the athletes would have been acclimatized and acclimatized until the last moment.

"When we arrived in Italy, we used all the heat protocols in our pre-training," Neumann continued. 'We had drinks and ice socks for the hot weather so we wouldn't over carbohydrate.

"I think yesterday was a great example of what can be done in a race to make sure all riders are well fueled and stay cool. We had a lot of support from the crew with bottles, popsicles, ice socks, etc. It may seem a bit traditional, but it's still the most effective way to cool off.

Dempster also noted that there is no need to unnecessarily complicate things when it comes to cooling. While Red Bull-Bohra-Hansgrohe athletes use medical cooling compression boots, Ineos Grenadiers' approach is much simpler.

"We have some equipment, but at the end of the day there is nothing complicated about it. It's like a bathtub filled with cold water. Just like if you're cold, you take a bath in hot water, and that warms you up."

"So we came back. You see a lot of ice vests and ice socks and things like that, but those are sensory things. If you put an ice sock on your back, it doesn't actually lower your body temperature.

In fact, the Ineos Grenadiers team used ice vests and ice socks before and after the first two stages of this year's Tour, but like many teams, the desire to lower body temperature before a race takes time for the body temperature to rise to a harmful level, resulting in only a slight only result in performance gains.

The average human core temperature is approximately 97°F (36.1°C) to 99°F (37.2°C). Output decreases by 5% for each 1°C increase (Racinais et al).

"If you can race in cooler conditions, that is the first thing to do, and then you are fighting a losing battle: overheating.

Interestingly, Norrell disagrees with Dempster's view to some extent. She believes that ice socks help lower body temperature, but is willing to admit that "it's a little bit of both."

She explained that "scientifically, cooling the base of the head and neck area is the most effective way to keep the body temperature low," and then added that there are other techniques to "trick" the body into feeling cooler, even if they have no physical effect.

"I think ice can really help cool the core body temperature, certainly as studies have shown. As you can see by actually doing different tests, covering your head with water can help you feel cooler while you sweat.

"Menthol is one of the things people use a lot. It's cool, it refreshes the mouth, and it refreshes the spirit, even if it doesn't change the situation. It's a technique that works in that sense, but we want people to use it as a secondary thing."

After a day of racing, many teams prepare an ice bath in the back of their van. Ineos Grenadiers, UAE Team Emirates, and Astana Kazakstan are three such teams, but Red Bull Bora Hansgrohe's approach is a bit more high-tech.

Team manager Ralph Denk, along with press officer Stephan Flessner, explained that the team uses the American brand Game Ready cold therapy wrap system. This system, which works similarly to the Recovery Compression Boots, sends cold water through the wrap to cool the body.

It also works with warm water, which of course is torturous in these temperatures. It is primarily a medical product and comes in a variety of shapes and sizes for different parts of the body, but the boots are used by teams and probably have the added benefit of compressing the muscles that the rider most abuses.

The DSM approach focuses on hydration and a gradual return to a normal temperature, rather than shocking the body with ice or high-tech solutions. Of course, this is a budget constraint for DSM, which does not have as deep pockets as the GC contending teams. [There have been several studies, including pool bathing and ice bathing," Nauman explains. 'In fact, studies have shown that ice baths aren't always completely effective. What we really focus on is hydration. We just have a recovery drink and a cold drink and follow the recovery meal protocol. Hydration is important after rest, and of course air conditioning helps a lot."