When I ran track in college (10 years ago, sigh), my team’s physical therapists were always pushing us to utilize any and all recovery tools, no matter how ridiculous they seemed to us college kids. We’d leave practice with protein shakes in each hand, our shins bulging with ice bags that were plastic-wrapped to our legs as we waddled on our way to the dining hall. We dutifully visited the training room three times a day to take an ice bath or get an ultrasound, transcutaneous electrical muscle stimulation, or the simultaneously loved and dreaded Graston massage. Foam rolling and mini-band work were staples.

Ever since then, I’ve been fascinated by how trainers and coaches can use recovery methods to make people better athletes, or simply bounce back from marathon training faster. When the Nice Rocc, a new handheld palm-cooling device that claims to improve athletic performance by rapidly speeding up muscle recovery, came onto my radar, I was intrigued.

Even better, the Rocc is manufactured in Boulder, Colorado, close to where I live in Denver. I got to drop by the Nice headquarters myself to see how this thing is made.

Super Fast Cooling

Palm-cooling, also called palmar cooling or vasocooling, uses the glabrous, or hairless, skin that humans have on the palms of their hands and the soles of their feet. This skin contains special blood vessels called arteriovenous anastomoses that contract quickly and widely, making them a great area to target if you want to cool core temperature. That aids in muscle recovery and helps athletes go harder for longer.

When you hold a palm-cooling device, it sucks heat from the body and sends cooled blood back into the circulatory system, dropping core body temperature fast. Athletes can take advantage of these tools during rest periods in games or between reps in practice. These devices are even being used to help firefighters and military personnel fight heat stress. As a performance tool, palm cooling is research-backed. Today, professional coaches and players in the NBA, NHL, MLB, and NFL, as well as tennis, soccer, and Olympic athletes, are using these products to get an edge in games and during training.

Nice has already established itself as an iceless recovery-tool maker with the Nice1, a portable cooling and compression device, but the Rocc is its first foray into cooling for performance instead of injury recovery. It’s a dense, rounded cylinder that weighs 5.3 pounds, but it has several factors that set it apart from other options on the market.

While most palm-cooling devices, like the CoolMitt, require some setup (usually in the form of adding cold packs or water to the vessel), the Rocc utilizes solid-state electronic cooling, similar to that found in mini fridges. Small squares inside the machine contain two different conductor metals that meet at a junction. Sending electricity to the junction triggers the Peltier effect, causing the outward side of the squares to feel cool, white the internal side of the squares heats up. (This heat is released through fans in the middle of the Rocc.)

All this means that you only have to make sure the Rocc is charged before you can use it. It can run for two hours on a single charge. Once you turn it on, it only takes about two minutes for it to reach the proper cooling temperature (50-60 degrees Fahrenheit). Dropping down to a lower temp causes those glabrous skin blood vessels to constrict, sending your cooled blood on its way through your body. Lights on the device let you know when it’s ready to go and the charge status.

Pushing It

Nice recommends the Rocc for anyone looking to amp up their training or competition performance, but you’re supposed to hold onto it for at least two minutes to get the best results. (A haptic timer vibrates every thirty seconds to help you keep track.)