It's first thing in the morning and I’m lying on a wooden floor wearing a coat over a swimming costume as a man chants and sings above me, accompanied by his guitar playing friend.
Normally, this is the kind of thing that would make me burst into laughter. But instead, I am completely calm and still, barely acknowledging the downright bizarre experience I’m currently having. In fact, I have been put into a trance.
The person guiding me through it is The Iceman Wim Hof. The Dutch adrenaline junkie claims his breathing exercises can allow people to withstand cold temperatures and unlock a host of health benefits from better sleep to reducing inflammation in the body and lessening the chances of developing heart disease.
He even credits his Wim Hof Method, which he created with son Enahm, with allowing him to achieve feats that are unthinkable for a human being to do.
He holds 21 Guinness World records, has climbed up the 26,000ft to Mount Everest’s death zone while bare-chested in shorts, spent almost two hours in an ice bath and reached the top of Mount Kilimanjaro in less than two hours, again wearing just shorts and shoes.
“I can do what scientists thought is impossible,” Wim, 62, says. “I did all those records just by learning to control my breathing. This method is very effective. Anybody can do it.”
We’ll soon find out if that’s true. Eight celebrities including Gabby Logan, Tamzin Outhwaite and Alfie Boe are set to try Wim’s method out for a new six-part reality series, Freeze the Fear with Wim Hof, which starts next week.
Presented by Holly Willoughby and Lee Mack, the famous faces move to a camp in the mountains of Northern Italy, where they face a series of cold challenges to “push their minds and bodies to the limit”.
Instead of Italy, Brockwell Lido in South London will be where I get a taste of what they experience – being immersed in cold water.
But first, I have to learn how to breathe properly, what Wim calls “the first pillar” of his method.
Wim says: “I do my breathing every day and still feel like I could take on the world. I never get tired. Tiredness gets tired of me! The oldest person I train is 100 years old, she started with me when she was 98. I’ve seen miracles.”
His exercises involve a cycle of 25 repetitions of breathing quickly in and out – but not hyperventilating – doing a big exhale and then holding your breath.
I manage to hold my breath for almost a minute and a half without really trying. It’s not quite on the level of Wim, who has held his for six minutes, but it surprises me.
As I come round from my trance 15 minutes later, I feel lightheaded and my feet and hands are tingling. While this would normally cause me a lot of anxiety, I am completely at peace with it.
When I breathe out, the air feels very clear. Although I’m in a heated room, my breath tastes very fresh, like when you step outside on a clear, crisp day and take in a massive lungful of oxygen.
“You were very committed to the breathing,” says Wim. “Anybody can do these exercises, anywhere. On a sofa, in bed, it’s very powerful.”
Breathing done and feeling tranquil, it’s time for Wim and I to go into the pool, which is eight degrees.
It’s a little warmer than the one the celebrities dive into in episode one of Freeze the Fear. That is closer to freezing and there’s visible ice – the temperature outside their pool is a bitter minus six.
Wim and I stand by the water where he starts shouting “do you feel strong?” which is slightly unnerving – but when I reply with “yes” he says: “let’s go.”
“I usually tell people to ease themselves slowly into cold water for the first time,” Wim adds.
However, I’m feeling brave after the breathing exercises - and I pride myself on being good in chilly temperatures.
I grew up in Newcastle and have had many a snowy, winter night out in the stereotypical Geordie girl uniform of a short dress with no tights or coat.
“I’m going to jump in,” I tell Wim firmly, and we both throw ourselves into the water. But the minute I hit the water my body betrays me and I start hyperventilating against my will.
It’s extremely embarrassing and I want to get out, but Wim guides me to the side of the pool, saying: “let’s relax.” “Take a deep breath,” he encourages. “You’re doing good. Inhale, exhale.”
After a couple of rounds, I ease up and even start laughing at myself.
“If you use your mindset well, you will be able to control stress and push it away,” says Wim. “It’s what you have done. The cold is a force, but we are stronger than it.”
Wim has always been drawn to the cold, telling me that as a teenager he had a sudden urge to jump into the icy water of Amsterdam’s Beatrixpark canal.
But it was after the death of the mother of four of Wim’s six children, his first wife Olaya, that he started going into cold temperatures regularly. Olaya took her own life in 1995 following a long period of mental illness, and Wim needed to combat the pain.
He says: “In the cold water, you don’t feel the emotional agony, you don’t feel anything – you’re just surviving.
“You have to adapt, so the thinking stops and your body takes over. That’s what I learned, and that gave me a little bit of relief, which was enough.”
The breathing came later, when he discovered that by breathing deeper and more mindfully he was able to withstand cold temperatures for longer.
For over a decade, Wim says he has “made millions” from training people and has coached A-listers such as Jim Carrey, Harrison Ford and Tom Cruise. And a Hollywood movie is in the pipeline, starring Joseph Fiennes as Wim.
However, despite his massive popularity, Wim has garnered scepticism from doctors due to claims that his method has reduced symptoms of illnesses such as multiple sclerosis and Parkinson’s disease – with no scientific proof.
Yet, its clear he is on to something . Just an hour after following Wim’s breathing techniques and swimming in the glacial water I was a completely different person - wide awake and elated.
Wim calls it “getting high off your own supply”. He adds: “You’ve been able to tap into your own power today. I want people in their living rooms to watch the show, and think, ‘I can do that too’. I want to change the world.”
Freeze the Fear with Wim Hof starts on Tuesday at 9pm on BBC One.