LAS VEGAS, Nevada - There are safety concerns over what's known as cryotherapy after a Las Vegas woman froze to death in a cryotherapy chamber.
Cryotherapy has really taken off since famous athletes starting using it, including NBA star Lebron James and boxer Floyd Mayweather. It's supposed to help people recover from muscle soreness, and some think it also helps trigger weight loss.
The cryochamber looks like something out of the future -- a metal box, lights and smoke pouring out. It's made famous by athletes who use it like an ice bath. But it's that smoke that may have helped kill 24-year-old Chelsea Ake.
"Chelsea was always a go-getter. She was always so happy and would help anybody," Shae-Lynn Bee, Ake's best friend, said.
Ake is being mourned by her friends and family. She worked at RejuvinIce, a sports clinic that offers cryotherapy.
Ake, after store hours, climbed in by herself. She was found 10 hours later, frozen in ice.
We do not know what happened, but medical experts have an idea and it might be that nitrogen-rich smoke.
"You could postulate that perhaps the nitrogen overcame, that's what made her pass out, and once she was passed out it continued and she froze to death," said Dr. Dale Carrison, with UMC Hospital.
Owners of RejuvinIce released a statement that reads in part, "We are all incredibly saddened... We firmly believe in whole-body cryotherapy treatments for pain management, athletic recovery and a variety of other ailments."
The owners also reaffirmed their commitment to safety by writing "we are voluntarily scrutinizing each and every one of our internal procedures to ensure nothing like this ever happens again."
Carrison is pushing for more research.
"With any medical procedure, advance in medical, it needs to be researched, it needs to be evidence-based medicine," he said.
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