Many fitness avenues — high-intensity interval training workouts (HIIT), battle ropes, kettlebell training — have one overarching goal: to make you sweat. This one, though, will leave you chilled (quite literally).

Cryotherapy, otherwise known as cold therapy, is when someone steps into a special cryotherapy chamber to brave temperatures as low as -166° Fahrenheit. Cryotherapy benefits include decreased pain and muscle soreness, reduction of inflammation and muscle damage, and calorie burn.

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Cryotherapy for athletes has undoubtedly been a growing trend: Floyd Mayweather, Lebron James, and Usain Bolt have all used it in training. But just how beneficial is cryotherapy, really? While the jury’s still out on many of the specifics, according to one study in the International Journal of Sports Physiology and Performance, it can be used to reduce pain.

That same study mentions that cold-water immersion sessions are even more effective than cryotherapy. (Spartan founder and CEO Joe De Sena, who uses a Cold Plunge as part of his everyday training regimen, is a diehard proponent of it.)

Is Cryotherapy Effective?

Bespoke Treatments co-founder Dan Giordano, DPT, CSCS, is wary of any alleged cryotherapy benefits.

“I think because we see it on social media and celebrities use it, that’s why it’s become so popular,” he says. “Although there’s plenty of research that shows the benefits of cold water immersion (ice baths and cold water plunges), there’s nothing conclusive about cryotherapy.”

That also means there’s nothing to say that the practice is detrimental. It really comes down to user discretion.

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“If you try it and you feel an effect, awesome,” Giordano says. “In that case, it doesn’t matter if the cryotherapy benefits are just placebo, as long as you understand that there’s no evidence that it can bring about a specific physiological adaptation.”

Interested in adding cryotherapy sessions into your training plan? Here are three important things you need to know before doing cryotherapy.

What You Need to Know Before Trying Cryotherapy

1. Prepare to Pay Up

Different cryotherapy centers will offer varying temperatures and durations to their clientele (both of which could impact how much you’re dropping for the treatment). A single session can cost you as much as $100, depending where you’re checking in.

“Cryotherapy isn’t covered by any insurance,” Giordano says. “So keep that in mind when you’re booking a session, and know exactly what you’re getting into.”

2. Dress Appropriately

Be prepared to strip down! While underwear is totally kosher, everything else comes off. Make sure to be entirely dry before stepping inside, since temps will be — literally — below freezing. The treatment center should offer you thick socks, slippers, and gloves to cover your extremities. And if you have any piercings, make sure to remove those before stepping into the machine.

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3. Consult With a Physician

Just like with a new training regimen or meal plan, it’s important to consult with an expert before trying cryotherapy for the first time.

“If you do have chronic pain or an injury, seek out a medical professional opinion prior,” Giordano suggests. “Manage your expectations, and don’t think it will cure everything.”