Paris Olympics: New mitt extracts heat from athletes’ blood, cools body

As the Paris Olympics draw near, athletes are gearing up to face not only their competitors but also the sweltering summer heat.

With temperatures expected to soar once again, following record-setting highs in 2023, athletes will encounter additional challenges in their quest for gold.

National weather agency Meteo-France predicts warmer-than-normal conditions for July 2024, though exact forecasts are still pending.

No air conditioning, no problem?

In line with its commitment to host the greenest Games ever, Paris 2024 will not provide air conditioning in the athletes’ accommodations. This eco-friendly decision means that athletes will need to be especially vigilant about managing their body temperatures during training, recovery, and competition.

“It can be very hot and miserable [in Paris], as it was in Tokyo during the last Olympics,” said Craig Heller, a biology professor at Stanford University who specializes in body temperature regulation.

“And that increase in environmental temperature has lots of effects on performance.”

Stanford University, renowned for its Olympic athletes, has been a breeding ground for medalists, boasting at least one alum as a medalist in every Games since 1912. In Tokyo 2020, Stanford-affiliated athletes secured 26 medals, while in Rio 2016, they clinched 27.

The university’s strong research and its location near Silicon Valley have helped create new solutions for athletes dealing with extreme heat.

CoolMitt: The cutting-edge solution for heat regulation

Among these innovations is the CoolMitt , co-invented by Heller. This device, designed like a mitten, extracts heat from the body by cooling the blood, which is then circulated back to the heart and muscles.

The CoolMitt can be used during breaks in events, between sets and reps in the gym, or any short pause in training or competition.

“If you take heat out of the core of the body, that prevents heat from building up in the active muscles, and they keep on working,” Heller explained.

“So what CoolMitt does is prevent hyperthermia, a rise in body temperature to a dangerous level. And therefore, it enables you to have a higher work volume. And if you have a higher work volume, you get a bigger conditioning effect.”

The CoolMitt targets glabrous skin surfaces—the non-hairy parts of the body that “contain specialized vascular structures that facilitate heat loss,” according to a study .

When athletes place their palms on the water-perfused pad inside the mitt, set to 50 to 53 degrees Fahrenheit (10 to 12 degrees Celsius), the device efficiently draws heat from their blood before it reaches the level of vasoconstriction, thus maintaining optimal blood flow and cooling.

Enhancing athletic performance with advanced cooling techniques

Tyler Friedrich, associate athletics director for applied performance at Stanford University, collaborates with athletes on strength and conditioning programs. He emphasizes the importance of temperature regulation for peak performance.

“We know if we are overheating, we will not be performing at the level that we want or that we should be. And so regulating heat and regulating core temperature in some instances can be critical and vital to perform at a high level,” Friedrich said .

While traditional methods like ice baths and cold towels are commonly used, their effectiveness is often questioned. Recent studies suggest that more research is needed to validate the efficacy of cold-water immersion practices.

However, Friedrich noted that the CoolMitt has made a noticeable difference.

“The athletes notice themselves feeling like at the end of the game they have as much juice or jump in their legs as they did at the beginning,” he remarked.

“That goes a really long way, both for psychological performance but also just for actual outputs and performance.”