It claims to zap up to 800 calories in 3 minutes. We braved temperatures of -90°C in the 111CRYO chamber to find out

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I’m feeling slightly jittery and very wide awake, like I have just pulled an all-nighter or run a 10k; there’s definitely something going on with my endorphins. What's more, I’m unusually hungry. It’s about an hour since I stepped out of the 111CRYO pod at Harvey Nichols, London. Developed by plastic surgeon Dr Yannis Alexandrides and his team of the 111 Harley Street clinic, it’s like a roomy shower cubicle but frozen to a breathtaking -90°C. It’s the first electrical (as opposed to liquid nitrogen) full-body cryotherapy chamber in the country and celebs have been loving it since is launched in autumn 2016. Nick Grimshaw, Winnie Harlow, Millie Mackintosh are regulars, as are the appropriately-named Sadie Frost and Lisa Snowdon.

Electrical cryotherapy apparently makes this a more cost effective treatment though at £95 for three minutes, it’s not something you could have by the hour (if it didn’t kill you first). In fact, the maximum three minutes standing in my provided kit – North Face slippers, gloves, sports bra and shorts, headband to cover my ears and a face mask to stop me taking a deep inhale of the icy air – are all I need to access an impressive list of health claims from weight loss to pain management, sports conditioning to ‘beauty enhancement’ - as well as helping with eczema and psoriasis it claims to improve skin tone and stimulate collagen.

Cryotherapy originated in Japan where it was used to treat severe arthritis; these days, athletes use it for recovery. Last month during the Six Nations tournament, the Welsh Rugby Squad made a flying visit home from to a cryo chamber to hasten their recovery from injury between games. But it’s the anti-ageing and weight loss aspects that are increasingly garnering attention. Good job I’m wearing the mask - a sharp intake of breath is my first impulse as I step into the deep freeze and watch the giant clock tick down three minutes as classical music pipes in. The warm air I bring with me creates a mist – which I’m warned about – and makes things slightly claustrophobic, but after about 45 seconds it clears and the therapist (a PT) stands outside and shows me some optional stretching exercises, which I copy more to take my mind off the cold than anything. It stings my skin, although my core temperature isn’t affected so I’m not really shivering.

The idea is that in the cold, blood vessels constrict and once back in the warm, blood rushes to the skin resulting in an energising glow and stimulating collagen synthesis. When my time is up, I step out and my skin temperature is taken, recording between 13 and 17°C on various parts of my body. My pre-Cryo111 readings were 34°C. According to Dr Alexandrides, 17°C is the threshold at which thermoreceptors in the skin sound the alarm and the brain sends out the big guns triggering your survival instincts. “This releases the hormones we are trying to take advantage of during Full Body Cryotherapy,” explains Dr Alexandrides. “By getting down to 17°C and below we are ensuring that your brain is being flooded with cold signals, the bigger the signals the bigger the response from the brain."  I feel very pleasantly toasty rather than cold and look pink as though I’ve just stepped out of a hot bath. For the rest of the day, my legs feel tingly and I feel decidedly caffeinated. I can see why some power types people uses it as a boost before a big meeting, it does make you feel ever so slightly superhuman.

I feel very pleasantly toasty rather than cold and look pink as though I’ve just stepped out of a hot bath. For the rest of the day, my legs feel tingly and I feel decidedly caffeinated. I can see why some power types uses it as a boost before a big meeting, it does make you feel ever so slightly superhuman.

My therapist goes into the chamber every day. How does he feel on it? He says he sleeps better – the endorphins help balance hormones, he says – and he hasn’t had a cold all winter. He is very slim (maybe he was 20 stone when he started, I’m so ‘high’ I forget to ask!).

So where do the weight loss claims comes from? Up to 800 calories a session – really? Apparently, the extreme cold kick-starts the body’s own self-regulating mechanisms to warm up, which increases your metabolic rate and uses up calories. Whether you burn up 800 calories or not depends on your body type and metabolic rate according to 111Cryo, although it's not clear how they measure this. I’ve no idea how much I burned but I’m certainly peckish. The good thing about the dry cold is that there’s no downtime. Wet cold - from an ice bath or a dip in an icy lake - has a more penetrative effect on the body, cooling it down more and requiring longer recovery.

The 111Cryo session is a speedy non-invasive treatment that harnesses the body's own healing and metabolic mechanisms.  I’m in and out in 20 minutes (the detailed health questionnaire beforehand takes longer than the actual cold treatment). The endorphin boost is real enough, as is the post-treatment glow.

A few hours after my treatment, I feel warm and glowy and still on a high that I survived three minutes at -90°C but my lungs feel a little tight and I’m not loving the enduring triple espresso feeling (although I’m sure this would be a draw for some). It’s the every opposite of the calm I try to cultivate in my daily yoga practice – and I don’t drink caffeine for that reason. Out of all the purported benefits, I’m most interested in anything that can knock years off my face. I didn’t notice a difference after the full body treatment but my face was partially covered by the mask and headband. Next time, I’ll opt for the new 111Cryo facial, which localises the cold (at -70°C rather than -90°C) on the face without amping up the entire system and involves some lovely 111Skin creams and a bit of lying down. Watch this space.

The 111CRYO full body treatment at Harvey Nichols costs £95.  Book online here . The 40-minute facial costs £75.  Book online.

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