It was a blistering 90 degrees, and humid, on a Saturday in September on the campus of Duke University, the football field transformed into a sauna. Midway through the third quarter, the opposing inside linebacker sacked Duke’s quarterback with a crushing blow.
The linebacker suddenly felt an unusual sensation — weakness — sweeping through his body. He tried to make it to the sideline but his muscles cramped, and his legs shut down as he nearly collapsed onto the trainer’s table. His hand was put into a device that vacuum-sealed his mid forearm down to his fingertips, and then … his body began to cool.
“It completely changed everything,” recalled Shayne Skov, Stanford’s All-American linebacker. “Within about five minutes, I almost felt as fresh as I did when the game started.”
The Cardinal football team, which won in a 44-14 rout that day in 2011, started using the device known as the Glove in 2002 to help with player recovery, and other teams at Stanford, and in the National Football League, have used it as well.
Stanford biologists Craig Heller and Dennis Grahn created the first generation of the cooling glove in 2000, after years of research on thermoregulation. It deals with the concept of thermal portals.
“These thermal portals reside on the palms of our hands and soles of our feet and this is how we, as humans, dissipate our heat,” said Brandon Marcello, director of sports performance at Stanford. “Animals have thermal portals also. Dogs have them on their tongues, rabbits have them on their ears and humans just happen to have them on their feet and hands.”
Marcello has been at Stanford since 2007, and he learned about the cooling glove in a meeting with Heller. Heller demonstrated the glove’s benefits and effects, and Marcello immediately brought the device to the Stanford athletics program.
“This device can cool you down faster by pulling the heat out of your thermal portals and replacing that heat with the cold fluid that runs from the cooler, through the entire glove,” Marcello said. “This drops your core body temperature, resulting in an enhanced performance effect.”
According to Marcello, if the body doesn’t expend energy in recovery as it tries to cool itself down, it can redirect that energy towards achieving an extended peak performance.
“It creates a negative pressure gradient so the portals stay open,” Marcello said, “and then there is a circulation of water, which goes through the glove, and it removes the heat from the body.”
Skov, who won numerous awards during his final season at Stanford as one of the nation’s top defensive players, said he used the glove about 10 times during his college career, in games as well as practices. He credits some of his success on the field to the glove.
“There have been at least six or seven instances during games where if I hadn’t used it,” Skov said, “I would have definitely been sidelined with cramps or passed out due to exhaustion.”
Unlike recovery techniques such as ice bathing, the cooling glove can be used during competition. Hot weather can have dramatic effects, and the cooling glove can help those physically drained athletes to a more rapid recovery.
Steve DiLustro, sports and performance coach for Stanford’s baseball team, has been using the cooling glove with his players for the past five years.
“We use the glove to cool off our guys, specifically our starting pitchers,” DiLustro said, “whenever we go to a hot environment like Arizona or anywhere where the temperature and humidity is high.”
In such scenarios, Stanford players will go to DiLustro in the dugout between innings, and he will hook them into the device. Depending on how long an inning lasts, this can give the athlete sufficient time to feel the glove’s rejuvenating effects.
Kenny Diekroeger — the former Stanford second baseman now in the Kansas City Royals minor league system — used the glove at the Super Regionals in North Carolina in 2011.
“The temperature and humidity was over 100 (degrees),” Diekroeger said. “I put my hand in the glove for a couple minutes after the first inning and instantly could feel my body cooling down and I stopped sweating. It boosts you back to 100 percent pretty much. It was honestly crazy the effect it had on me.”
The cooling glove is a lightweight mobile device. You only need to have ice water in the cooler portion of the glove and make sure the battery is charged.
Daniel Garza, former Stanford doctor and team physician for the 49ers, who died last October, brought the cooling glove to the franchise.
“We use the glove primarily for health reasons. But outside of sports, it has potential for a lot of exciting things,” Garza said in a 2008 interview with the San Francisco Chronicle. “This technology is a much more effective way of cooling the core temperature than what we would typically do — misting, fanning, cold towels, fluids.”
The military has started using the glove to help keep soldiers on the field of battle, under intense conditions. It is also being used to help treat stroke and heart attack victims.
Heller and Grahn are co-founders of the AVAcore Technologies Group, which was formed in 2000, about the time the glove was first developed. AVAcore Technologies is the only company that sells the patented cooling glove device, which originally cost about $2,500. A second generation of the glove now retails for $995 on the AVAcore website.
“I don’t know if it’s the future,” Marcello said, “but it definitely is the present. People are going to continue to use this device and it is a huge part of the recovery puzzle, as well as a necessary piece for an athlete’s success.”