AUSTIN, Texas — The sweaty elephant in the paddock at the Lone Star Le Mans is that it could’ve been worse.
Central Texas has suffered triple-digit heat for weeks — Thursday’s 103-degree high even scuttled drivers’ traditional track walks. But the remnants of Tropical Storm Edouard brought a merciful breeze, a cameo of clouds, and a spit of rain; with race day peaking at 97 degrees, this Texas endurance-racing test might have actually gotten lucky.
Inside the closed cockpits of WEC’s two classes of sports car, the difference may be academic.
“It’s very tough. I think physically it’s the toughest race of the year,” said Sébastien Buemi, who races for Toyota’s Hypercar program.
WEC is a sport of hours-long stints behind the wheel, split between three drivers. The series and its governing body, the FIA, go to great lengths to keep drivers cool and safe in both the Hypercar and LMGT3 classes, from fitness preparation and hydration plans to in-car cooling equipment.
The FIA’s regulations set a limit on how hot a cockpit can get, and this limit is rigorously monitored and enforced.
But the drivers’ vital signs are not monitored on track, and some of the available cooling equipment receives mixed reviews from drivers and experts. Some behind-the-scenes at WEC acknowledge that more can be done to keep drivers safe as temperatures rise.
Austin is the hottest race WEC runs. The series races for six hours at the Circuit of the Americas on Sunday, starting at 1 p.m. The city’s September average is 86 degrees, and locals will tell you that the real average is about ten degrees warmer. The endurance racing series also runs in Qatar and Bahrain, but only at night. For most of the season, WEC runs in European locales during the spring and early summer. Austin is where WEC takes the heat head-on.
Dr. David Ferguson, an associate professor in Michigan State’s Department of Kinesiology, has spent 20 years trying to get motorsport to take overheating seriously. He runs the Spartan Motorsport Performance Lab and chairs the International Council of Motorsport Sciences.
Ferguson is the closest thing the field has to an authority, in part because the field is so small. By his count, roughly 60 scientific papers have been published on the physiology of racing drivers since 1967. Soccer, he said, produces around 800 a year.
The physics of heat on a driver’s body is brutal. A driver in a Hypercar puts about 25 pounds of force through the wheel each time they turn it, and between 75 and 150 pounds of force into the brake pedal.
Drivers will be in the cockpits for at least two hours each on Sunday (James Moy Photography/Getty Images)
All that work creates energy, which produces more heat. So do the engine, the drivetrain, the burning tires and the sweltering track surface. Left unventilated, according to FIA technical delegate Fabrice Van Ertvelde, a closed cockpit can “easily” reach a little over 160 degrees.
And the fireproof suits drivers wear work in both directions: they keep fire off the skin and keep the body’s heat in. When you sweat, the body is trying to cool itself, “but because of the fire suit, that’s really compromised,” Ferguson said.
If not regulated, he added, a driver’s core body temperature climbs into the range where “we start to have concerns about hyperthermia, heat risk, heat stroke — whatever you want to call it. That’s where cognition becomes impaired, muscle contraction becomes impaired, and metabolism actually slows. It can be very bad.”
In WEC, which runs races as long as 24 hours at Le Mans, the FIA’s current focus on driver safety and heat centers on determining when a cockpit is too hot to race in and then intervening.
A sensor sits to the left of and behind a driver’s helmet, continuously reporting the temperature to the FIA’s electronic monitors. Throughout the weekend, Elliott Martin, the FIA’s WEC electronics manager, and a small team commandeer a trailer at the back of the paddock, keeping an eye on dangerous data coming off the cars.
When outdoor temperatures are 77 degrees or cooler, the cockpit temperature must not exceed 89.6 degrees. In hotter weather, the limit is the outdoor temperature plus seven degrees. Exceed the limit, and the penalty is a stop-and-repair pit stop under a black-and-orange flag. There is no warning, no second offense, no discretion.
When a car gets flagged, the racing team gets a note (copied to the FIA) and a short window to fix it. Martin can see in the data whether a team’s air conditioning is running, and he said teams sometimes say they’re switching it on just to buy time while the numbers come back down.
Ambient cockpit temperature data is relayed real-time to the FIA (Andrea Lorenzina / DPPI / FIA)
Asked whether the system could be gamed in other ways — whether a team or driver could direct any airflow at the sensor and run the rest of the car hotter than the rule allows — Van Ertvelde shook his head.
“No. We would see it,” he said. “It’s too obvious — and on the other hand, it’s for the driver’s safety … there is no interest (from teams) because we’re going to knock them back immediately. The risk is too high.”
Standing beside a Toyota Hypercar in the team’s COTA garage on Friday, Van Ertvelde pointed out the cooling options available to teams. Two small ducts gather air passing over the car’s nose and open onto the driver’s chest, which they can crack or close themselves on track. Some drivers have helmet blowers, and seats that feed air. And for a weekend like this one in Austin, an air-conditioning box gets added to the cockpit, plumbed by two blue lines to connectors at the driver’s left hip, feeding a tubed shirt worn under the fire suits.
Whether and which system is used is up to the teams each race, as long as the system is one approved by the FIA. At an ordinary 75-degree race, some cars run nothing beyond the ducts, and a driver gets what air naturally enters the cockpit.
Buemi, who has been doing this since 2012 after leaving Formula 1, described the system without much affection. “When the air is so hot, it doesn’t really matter that much,” he said. “It’s like a hairdryer — and that’s the only air that comes in.”
The reason most teams stop there is not indifference as much as compromise. Everything added to a race car costs some lap-time performance, and in racing, performance is everything.
Robert Kubica used a helmet blower at the 2026 race in Sao Paulo (Photo Andrea Lorenzina / DPPI)
“This is an additional system. It’s additional weight, additional power,” Van Ertvelde said in the Toyota garage, “and the technicians, they do not want to use it.” Nearby, a technician laughed and nodded in agreement.
That trade-off is a real hang-up. Ferguson’s lab once showed that a driver who is cool and hydrated will be a few seconds faster than one who is overheating.
“I thought that was going to be the most fundamental thing: walk up to an engineer or a team principal and say, ‘The data says this,’” Ferguson said. “And some of them were like, ‘Yeah, that’s great, but if I add half a kilo here, that’s going to cost me this (in extra lap time).’
“It just didn’t translate.”
When asked by The Athletic over email whether the series has ever considered mandating a standardized cooling system in every car, an FIA spokesperson replied that “teams have the opportunity to choose the solution that works best for their particular car architecture and operational needs.”
Races like Austin force the issue, however. Van Ertvelde said most of the field this weekend is running the full cooling package — ducts, fans, chiller and driver cooling shirt. Whatever the sport currently knows on what to do about overheating, it will be doing on Sunday.
And Ferguson’s lab has tested most of it. It put trained subjects in full FIA-approved racing gear on a stationary bike in a heat chamber at 90 degrees and 80 percent humidity. The results, published this year in the ‘Medicine and Science in Sports and Exercise’ journal, ranked a suit blower running cold air first and a cold-air helmet blower second.
“I do not recommend the cool shirt,” Ferguson said of the liquid-cooled tubes affixed outside a thin shirt, circulating cold water. Ferguson’s study tested a shirt developed by Rini, which is used by NASCAR. The shirt, approved by the FIA for WEC and F1, is made by Chillout Motorsports and is by far the most widely used cooling device in motorsport, used across the grid at Sunday’s F1 Italian Grand Prix. According to Ferguson, the shirts can fail in the same way regardless of manufacturer.
Asked how long his shirt stays cold, Buemi scoffed. “It gets warm from the beginning,” he said.
A Toyota team member demonstrates the cooling shirt (Andrea Lorenzina / DPPI / FIA)
Ferguson estimates that cool shirts fail roughly 20 percent of the time. Overheating or air bubbles cause the mechanism to enter limp mode, circulating fluid without cooling it. “So now you’re putting hot liquid on your chest, and that will heat you up,” Ferguson said.
Two doctors from Formula Medicine, an Italian center for driver performance working with BMW, which runs two cars in Hypercar in conjunction with the WRT team, directly addressed the suit’s cooling duration.
“That’s a problem,” said Dr. Alessandro Lucchini, who is with Formula Medicine and BMW as part of his sports medicine residency. “Even in races that are slow (like cycling), that’s a problem.”
In a written response to The Athletic, the FIA said, “There are no particular concerns as long as systems used are FIA-homologated and used according to manufacturer’s prescription. To date, we have never experienced issues.”
Gabriele Polcari, a Formula Medicine physiotherapist working with Lucchini, stated that cooling equipment is merely a last line of defense, with fitness preparation being the primary focus. WEC drivers expend 600 to 800 calories per hour, burning up to 2,000 calories per stint, and require high-carbohydrate diets to prevent performance decline.
BMW tracks drivers’ fluid loss by weighing them upon arrival and before and after each session. Drivers receive chilled (not iced) drinks, use cooling spray on their underwear, take ice baths after a stint, and stay in hospitality units kept at 72 degrees to avoid wild temperature shifts before stints.
Fitness remains foundational. Polcari and Lucchini emphasized that aerobic fitness reduces sweating and heat suffering, calling high physical fitness nonnegotiable for modern drivers.
But once they’re in the car, the sensors only pick up the temperature around them. Ferguson’s studies point to biometric data as a more useful tool: body temperature, heart rate and other metrics can give a “pretty good idea” within five or 10 laps of when a driver will start losing lap time to fatigue or overheating.
“I’m very keen on measuring more on the actual driver — heart rate and things like that,” Martin said. “I personally think that we could do something novel. It would be a tremendous step to take.” The FIA confirmed to The Athletic that, in WEC, biometric data is not collected in real time and that such live monitoring systems are not permitted under the regulations. In the event of an incident, the current system requires a medical team to reach the driver after an incident, make an assessment and then transfer him to the medical center.
The caution behind biometric devices is reasonable: any device on a driver must not pose a hazard, withstand fires, and prevent skin burns. This same safety priority forces cooling tubes to be placed over shirts rather than directly on the skin.
The end of the air intake ducts feed air to try and cool drivers in Toyota’s Hypercar (Toyota)
If Ferguson had his way, the future would look like this: drivers fitted with validated, fire-safe sensors for heart rate, skin and core temperature and sweat rate. Cooling and hydration hardware designed for a race car, not adapted from elsewhere.
There would then be someone on the timing stand or in the electronics booth whose only job is to monitor the driver’s data, the way an engineer monitors a car, making calls that serve both driver performance and safety.
And all of it would be routed automatically to the track medical center, so that if there’s an accident, the doctors know the driver’s state before they reach them.
“And then I would retire,” he said.
Everyone seems to agree that it’s good for monitoring to be out of a driver’s hands because, no matter the preparation around the race, once on track the driver may not be aware of when he’s reaching the limit — or may ignore it.
Drivers notoriously focus intensely on performance, and, like any athletes, have learned to ignore cues everyday people may follow. “They’re living for a moment — to achieve points, a championship, a win, whatever it might be,” Ferguson said. Polcari recalled one who rejected prep and nearly collapsed after a stint: “He was like, ‘I don’t need that.’ Well, maybe you needed that.”
So say all of it arrives. Say Ferguson’s dream comes true and he gets to retire. There will always be drivers like Buemi, who, when asked whether drivers now prioritize health over results on track, locked eyes and furrowed his brow.
“No. Once you’re in the race, you push it to the limit. There’s so much at stake. People have been working so hard for it.”
When it’s this hot and you win, he said, “It feels special.”
