in NYC but has since come to London

FEMAIL writer Marianne Power tried out the latest exercise trend to hit the UK, naked yoga

When I'm stressed I have two recurring dreams. One involves me in an exam hall about to take a paper that I have not revised for.

The other features me walking down Oxford Street with no clothes on. I'm trying to hide but then I see someone from work. I wake up in a cold sweat.

For most us, being naked in public is the stuff of nightmares.

So why is it that here I am, on a Sunday night, about to take my clothes off in front of room full of strangers who have all paid good money to do the same thing?

And not only are we going to take our clothes off – we are going to bend and move ourselves into the most compromising of positions. And no, it's not that kind of a get together.

It's the latest fitness trend to hit London: naked yoga. Yes, really.

The craze started in the New York where naked yoga classes have got a cult following.

Matthew McConaughey is said to be a fan, while Lady Gaga featured naked yoga in one of her music videos.

Trendsetting magazine Gentlewoman featured a whole naked yoga shoot while a high-end naked yoga retreat in Ibiza sold out this summer.

The idea behind it is that it helps people get over body hang-ups – but surely us Brits are too uptight for naked downward dog or sun salutations in the buff?

Apparently not.

Yoga teacher Annette, founder of Naked Yoga London, says that since she started her naked yoga classes a couple of years ago, the demand has been overwhelming.

'The feedback from the courses was so overwhelmingly positive right from day one. I was blown away, and still am blown away by the messages I receive from people having attended the classes,' she says.

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The craze started in New York and has since progressed to London where classes are in high demand

'The benefits range from simply feeling great and free, experiencing the liberation of your body free from clothes and moving in contact with the air, and also a sense of psychological liberation in this.

'People say they become more accepting of themselves, they get over weight issues, they become less self-conscious and less judgmental of themselves and others.'

That sounds nice.

Although I don't actively hate my body, I don't love it either. My bum is fat, my thighs wobble, I have cellulite, I have scars. I try not to think about it because I know that I'm very lucky to have a healthy body that works and as a size 12-14, I'm a very normal size – but the truth is I have a kind of low-grade body-loathing all the time. It's boring and draining.

If naked yoga can change that, then I'm willing to try – but I'm terrified.

The process is supposed to help participants relax and feel comfortable in their own body

My first fear is that everyone will have perfect yoga bodies so when I arrive at the tiny studio in South London I am relieved that everyone looks quite normal.

We are all ages from twenties to sixties and about two thirds men, one-third women. We are all shapes and sizes – from what I can see at least.

Once we are in the dimly lit studio everyone keeps their eyes to themselves.

The room is warm and there's a smell of incense and the soft sound of plinky plonky music. Mirrors and windows are covered and candles flicker.

We're told to find a mat, get 'changed' – ie undressed – and lie down. I won't lie – it's embarrassing. I find a spot in the shadows, remove my leggings and jumper, take a deep breath as I take off my bra and knickers and lie down quickly.

I don't look at the two men on either side of me doing the same. It's amazing what you can block out.

I work hard telling myself that they were enlightened yogis and not perverts – but the truth is the whole thing feels very strange.

We begin. Annette's soothing voice guides us through the postures.

Fortunately the mats are arranged in a horseshoe shape and at a diagonal so that we each face Annette but are not looking directly at other people – and nobody is behind you.

It is also a relief that most of the class is done lying down with eyes closed. There's lots of deep breathing and gentle stretching and lifting of arms and legs from a lying down position. In the few minutes I manage to forget I'm naked it's surprisingly relaxing. The dim lights and soft red candles make the whole thing feel like being in the womb.

When the moves got a bit more dynamic I do get self-conscious. I have moments – when doing the downward dog – where I think, 'What the hell am I doing?' but at no point do I get an eye-full. I try not to think who might be getting an eye-full of me.

I treat it all as a mental exercise in not caring what people think. This class is more about being in your own body than looking at other people's.

And in that semi-dark studio, with Annette's soft voice telling us to 'inquire' into our breath, something quite miraculous happens.

Marianne says that she found the experience very effective and the class left her appreciating her figure

Towards the end of the class, I find that I like being in my own body. I'm not criticising it, hating it, wishing it to be better. Even when my tummy was hanging down it didn't bother me. I marvel at how my body could bend and move, and at my soft droopy skin. In the soft candlelight it doesn't look so bad.

Annette says this is exactly the benefit of naked yoga.

She says: 'We have such high and unattainable standards of what our bodies should like. People can feel inadequate, insecure and dissatisfied with themselves. Part of the reason I do naked yoga is to react against these ideals of perfection...

'Our bodies are a wonderful miracle granted to us as human beings, and we spend far too much time criticising them, hiding them away in shame and fear. It's time to love, honour and delight in what our bodies have to offer us.'

At the end of the class there's a quiet calm as everyone puts on their clothes and walks to the tube. I speak to the lady who was just as nervous as I was, when we walked into class at the beginning.

'That wasn't so bad, was it?' she asks me. 'No, it wasn't – actually I liked it,' I say. 'Me too!' She's grinning now. We both are.

I get home and can't quite believe what I've just done. It's like a dream – but not a bad one this time. Weird but not bad. In fact, it was quite beautiful.