Nestled in midtown Manhattan, just a couple blocks south of Central Park, is a self-proclaimed health and wellness center called KryoLife, where clients are blasted with super-chilled air that’s between minus 184 and minus 264 degrees Fahrenheit.
They like it so much, KryoLife co-founder and CEO Joanna Fryben told Business Insider, that over 90% of first-timers come back a second time.
The chilly experience is widely used in Europe to relieve certain types of pain and is growing increasingly popular in America, especially among professional athletes and celebrities.
To see for ourselves what all the fuss was about, Business Insider sent a few of our reporters to the center where Graham Flanagan took one for the team.
Whole body cryotherapy was invented in the late '70s in Japan as a way to reduce pain due to inflammation in arthritis patients. According to KryoLife's CEO TKTK, many of its more than 1,000 clients are looking to ease pain due to some type of inflammation.
In a room about the size of a modest walk-in closet is KryoLife's chamber. The center has just the one chamber at their Manhattan base.
Tucked in a corner is one of the center's large tanks of liquid nitrogen. At room temperature and standard pressure, liquid nitrogen boils, and it's the resulting nitrogen gas that fills the chamber.
Liquid nitrogen is about -330 degrees Fahrenheit and will therefore cause instant frostbite if it contacts the skin. But nitrogen gas is less brutal. The tanks safely store liquid nitrogen in vacuum tubes that then release the gas through pressurised valves and into the chamber.
When the machine is in action, the entire chamber fills with nitrogen gas, covering every inch of exposed skin (except the face). Because the air is so much colder and denser than its surroundings, it automatically stays within the chamber.
Although nitrogen gas won't cause instant frostbite like it would in its liquid phase, it does pose some danger to the smaller extremities like fingers and toes during the treatment. That's why every KryoLife client wears clogs, socks, gloves, and underwear while in the chamber.
Being inside the chamber causes your blood vessels to constrict, which tends to raise your blood pressure. As a precautionary measure, a KryoLife professional will always take your blood pressure to confirm it's not too high for you to begin the treatment.
Before entering the chamber, reporter Graham Flanagan was extremely anxious. Once the temperatures began to plummet, though, his enthusiasm and energy got a noticeable boost.
Throughout the 3-minute procedure, KryoLife co-founder and CEO Joanna Fryben monitored the time and temperature -- in degrees Celsius -- inside the chamber.
After his 3 minutes were up, Flanagan re-robed and exited the chamber. He was surprised, he said, to feel so full of energy. He said he felt like he'd just gotten off a roller coaster.
In a bike in the adjacent room, Flanagan got a chance to expend some his new energy. You don't have to use the exercise machines, but they're there if you want them. Fryben explained that whole body cryotherapy can, in some people, release a rush of endorphins, which is likely what was causing Flangan's boost in mood and energy.
KryoLife customers are instructed to keep their heads above the chamber -- there's hardly any breathable oxygen inside once it's filled with nitrogen gas. But, if you want your face to feel the same chilly effect, Fryben told us, they have something for that, too.
They call it a facial. Here, Fryben is shown using a tube to blow some of the nitrogen gas onto Flanagan's face. Flanagan said this experience made his face feel cold and rejuvenated, similar to how you might feel after skiing down hill on a cold, windy day.
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