Two minutes is the average length of a commercial break, and it irritates enough of us that fast-forwarding live TV is a common habit. Now imagine standing in a subzero cryotherapy chamber for that same length of time. Living without a DVR doesn't sound so bad, does it?

But what is cryotherapy, exactly, and why would anyone put their body through that? To find out the answer, we interviewed Jim Karas, the owner of Chicago CryoSpa, and Groupon beauty blogger Favin, who tried out cryotherapy at his facility. Here's what they had to say about the subzero wellness treatment:

What is cryotherapy?

Cryotherapy is like "an ice pack on steroids," Jim says. That's why it's so popular with athletes and those who suffer from chronic pain—the intense cold is said to minimize inflammation from injuries and ease the recovery process. Best of all, you only have to spend a few minutes in the chamber, as opposed to the 6–10 minutes you might have to spend in a traditional ice bath to get similar results.

Cryotherapy is like "an ice pack on steroids."

– Jim Karas, owner of Chicago CryoSpa

What does cryotherapy cost?

You would think that a treatment used by such high-profile athletes as LeBron James would be pricey, and you wouldn't be wrong. A single session typically costs between $60 and $100, and the cost depends on the market. In Chicago and LA, for instance, cryotherapy tends to be closer to $60 (it's $65 per session at Jim's place), whereas in New York, it tends to be closer to $100. However, a Groupon deal for cryotherapy usually cuts the price in half, sometimes more.

Another way to save on cryotherapy is to opt for a package of treatments or to get a monthly membership that offers special pricing for repeat visitors. But why would someone want to come back all the time?

Favin, who suffers from a herniated disk, wanted to try the treatment to see if it would help ease her back pain. She felt so much better afterward that she committed to five consecutive days of cryotherapy the following week, despite the fact that she was "scared" at first and worried about becoming a Popsicle in the frozen chamber.

What happens during a cryo treatment, exactly?

• Step 1: The client puts on the proper garments. Men wear close-fitting shorts. Women are either naked, like Favin, or wear shorts and a sports bra. Both men and women wear gloves and socks to protect their fingers and toes. They also wear a robe until it's time to get into the chamber and hand it over to the supervising staff member.
• Step 2: Under the staffer's watchful eye, the client steps inside a cylindrical chamber about as tall as their shoulders, leaving their head and neck exposed. After disrobing, their body is bathed in liquid nitrogen or refrigerated cold air, with temperatures dipping to -250 degrees Fahrenheit.
• Step 3: The client remains in the cold for 2–4 minutes, depending on how experienced they are with the therapy. Favin stayed in for two minutes. Those short durations keep the body's core temperature at a normal level even while skin-surface temperature drops by dozens of degrees.

Our cryotherapy video can show you what to expect:

What does it feel like?

Really cold. As the temperature plunged throughout the two-minute session, Favin's technician tried to distract her, telling Favin to watch the flat-screen TV or spy on passersby on the street outside. Favin says it was hard for her to focus on anything but the cold, but as soon as she stepped out of the chamber, she felt "instant relief."

"My skin was covered in giant goosebumps, but they faded as soon as I jumped on a stationary bike. The pedaling helped blood to flow back into my limbs, and warmed me up within a minute or so," she explains.

As soon as she got warm, she felt a rush of energy from the adrenaline coursing through her body (Jim says that rush of energy is common). More importantly? Favin noticed that her back didn't hurt quite as much.

"At the end of that week, I drove to Cincinnati to visit family. Sitting in a car for that long would typically set my back on fire, but I felt great the entire weekend, even when I was chasing my cousin's baby around."

"At the end of that week, I drove to Cincinnati to visit family. Sitting in a car for that long would typically set my back on fire, but I felt great the entire weekend ..."

– Groupon beauty blogger Favin, after trying cryotherapy

So how does cryotherapy work?

Although cold therapy has been used for ages by athletes recovering from injuries and overworked muscles, there hasn't been a ton of research on it. But here's what proponents say cryotherapy does:

• It reduces skin temperature. The cryo chamber causes a significant drop in surface body temperature, which may cause the brain to think that you're in distress. The brain responds to cold by sending blood to the core and away from the extremities. Once you step out of the chamber, oxygenated blood is redistributed to the extremities.
• It constricts blood vessels. Vasoconstriction limits blood flow to the cold-affected areas (in this case, most of your body), which helps reduce inflammation.
• It has a psychological effect. Jim says that many clients report feeling energized and euphoric after a session. The release of endorphins and adrenaline may help elevate your mood, researchers suggest, but there's not a lot of evidence to say so conclusively.

What does it treat?

Again, not a lot of research has been done on whole-body cryotherapy, and the FDA has not approved it as a medical treatment. But proponents say it helps with musculoskeletal pain by reducing inflammation and possibly triggering cell repair. And localized cryotherapy, applied to the head via hand-operated tool, may relieve headaches. A lot of their information comes from anecdotal evidence of pain relief.

What if you want to try cryotherapy for weight loss?

Some proponents say that when the body sends blood rushing to your core during those two minutes in the chamber, that increases your body heat and, subsequently, your metabolism. However, again, there's really no evidence to support that right now. Still, the treatment does have plenty of celebrity fans.

Who can't get cryotherapy?

According to Jim, people with larger builds may not be able to use certain equipment because skin cannot touch the interior walls. (Think of the famous tongue-to-pole scene in A Christmas Story.) And he says it is not recommended for those with severe high blood pressure and heart problems.

Cryotherapy Reviews

Here's what some of our Groupon customers have to say about their subzero experiences:

"Epic! CryoSpa was amazing. In and out in less than 10 mins. Since it's a dry cold you do not get that frozen feeling like a polar-plunge jump. Definitely will do this again. If you're sore from working out or training then this is a must!" – from Jeff W.'s review of Chicago CryoSpa

"For my first cryo experience, I absolutely loved it. I don't know if I could have handled longer than a three minute session, but I loved how I felt afterwards. ..." – from Kiyomi S.'s review of Mend Cryotherapy in Santa Clarita

"This place is amazing! ... The last time I [had a] migraine for 3 days and with only one facial cryotherapy, I was migraine free." – from Inester G.'s review of Cryo Guru in New York

Watch our two beauty editors Rebecca and Amelia pump each other up for their cryotherapy experience:

Have you tried cryotherapy? What did you think?