Benefits of exposure to extreme cold voluntarily 'very limited,' says researcher

A researcher says evidence is"very, very limited" when it comes to the benefits and safety of cryotherapy.

The practice of exposing people to extreme cold temperatures for short periods of time dates back to the ancient Greeks.

It is not a new concept but has become popular in recent years, withcryotherapyclinics opening up across the world. Claims have been made by manufacturers of cryogenic tools and the clinics that use them that the practicecould help treat things such as muscle soreness, rheumatoid arthritis and even aging and wrinkles.

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JoeCostello, a lecturer at the University of Portsmouth inEngland, studied the use ofcryotherapyto reduce muscle soreness in particular.

"We concluded that there is simply not enough evidence to categorically say if this treatment is or is not effective to reduce muscle soreness after exercise."

During whole-body cryotherapy, people will typically be exposed to temperatures of 60 C for 30 seconds in a pre-cooling chamber. From there, people will move into thecryotherapychamber where they will be exposed to temperatures of 110 C or lower for a duration of two to three minutes.

For reference, the coldest temperature ever recorded on Earth was 89 C, in Antarctica.

Those who decide to undergo the treatment typically strip down to their underwear, save for some precautions when they enter the chamber, such as sandals or wooden clogs, doubling up on socks, gloves and something to cover the ears and face, if necessary.

Costellotried it for himself.

"There's a cascade of physiology that occurs when your body experiences that extreme cold," he said. "You get an increase in your breathing;your skin cools rapidly," he said. "It's quite an unusual experience and rather hard to describe but I can assure you it's very cold."

A single session could cost as much as $60.

Costello said it's not uncommon for people to dish out money for a therapy thatisn't fully understood.

Trends and methods in use by professional athletes will trickle downto recreation athletes, he added.

"I would advise people to be careful in the extreme cold conditions," he said. "Make sure outside time ... is kept to an absolute minimum."