PARIS, France — "I like to say we live on the thermal edge of life and death," said Dr. Craig Heller, a biology professor at Stanford.
As he explains, our bodies regulate at about 98.6 degrees Fahrenheit. Only a few degrees above that is considered heat stroke.
In Paris, during the first full week of the Olympics, the 90-degree temperatures are raining down on fans and athletes alike.
"You can literally cook your own muscles," Heller said. "Muscles produce a lot of heat, and the way that heat gets out of the muscle is through the blood."
Heat can also affect the brain, according to Heller. He said we can't think straight once our bodies reach a certain temperature.
"You need to have a cool head," said Heller. "That has a real meaning."
Heller discovered and developed new technology to remove heat from the body. The process works in a matter of minutes.
When it comes to athletes who are in training or competition, they use a CoolMitt, which Heller said has a water-perfused pad circulating water at just the right temperature.
"There are special blood vessels in the non-hairy skin," Heller said. "So the non-hairy skin is the palms, the soles and the face."
This technology helps pull the heat directly from those special blood vessels. That's why it's designed to be worn like a mitt.
"The muscles just keep on working, and what we've found is that has a tremendous effect on performance on muscle fatigue. It essentially is a way of extracting muscle fatigue from the body," said Heller.
Research and development started about 20 years ago, when Heller was working on another project. He said he stumbled upon this information by mistake.
"If you keep your eyes open, and you see things that look like mistakes frequently, it's the next best thing," Heller said.
Now, Heller said CoolMitt is used by several athletes on Team USA, including those competing in wrestling, swimming, cycling and fencing.
"We can see now with climate change," said Heller. "Hyperthermia has become a real problem."
In 2023, about 2,300 Americans died from heat stroke, according to Heller.
"That's probably a gross underestimate, because hyperthermia can precipitate other events, such as heart attacks," Heller said.
That's why he said it is important for everyone, not just high-performing athletes, to care for their bodies in the heat.
Signs of heat stroke can include red or damp skin, headache, dizziness, confusion, even loss of consciousness.
Experts suggest calling 911 right away, since heat stroke is a medical emergency.