A writer who doesn't do exerise (just lunch) tries out a gruelling new bootcamp... with hilarious and rather-painful results.

YOU'RE late,' barks a woman wearing a whistle around her neck and a scowl on her face. 'Where have you been?' 'We've been waiting an hour,' a woman in a pink anorak pipes up. 'I was up at six this morning to get here,' spits another. I giggle nervously and am about to relay my rubbish taxi-driver saga to the 17 faces trying to kill me with laser-gun stares but a handsome man in a track suit wants to know if I've brought my medical release form. 'Uh, no.. .' The whole room tuts.

The woman with the whistle is giving me the same look my school sports teacher gave me when I left my togs at home. And when I scored an own goal in hockey. And when I cried off sick on sports day with cramps. The look that says: 'You're a loser, I despise you' - the look that ensured that the day I left school was the last time I ever participated in any group sports activity. This was all a horrible mistake.

When my friend asked me to take part in a day-long weight-loss bootcamp in the Wicklow mountains, my first reaction was 'No, no, no, no... a thousand times no.' I don't do exercise, I do lunch.

And besides, even if I was the kind of person to do exercise it would not be in conditions that make Nam look like a holiday camp. Military style fitness bootcamps might offer the kind of no-frills rain-soaked agony that seems fitting in our recessionary times - but it's not my fault the banks went bust.

I had another friend who did one in Wales. 'It was brilliant!' she told me. 'They kept yelling at you, so you couldn't stop. I was so tired I vomited!' WHAT?! Has the world gone mad? If you feel the need to vomit in public why don't you do it at four in the morning, like all normal people?

To be shouted at, just go home to your parents. At least that's free. But days later I had a change of heart courtesy of a Zara changing room. While struggling to get the zip up on an XL dress, I was victim to a two-prongued mirror attack. To the front a greasy, flakey, spot-ridden face that proved my concealer was not doing its job. To the back, well, the kind of wobbly behind I'd see on old ladies in the swimming pool as a girl. It was truly sobering.

My finely tuned regime of caffeine, alcohol and almond croissants was clearly doing me no favours. As for pretending that walking to the shops counts as a work-out, well, I've been delusional. For the first time in a long time, I saw myself as I really was. And It wasn't pretty.

I e-mailed my friend: count me in.'You won't regret it.' she e-mailed back. 'I know I will,' I replied.

9.AM The Hike

WE START with a hike up a mountain.It's drizzling and cold. Our group is 16 women of all shapes and sizes, from 20 to 50, and one man who has been dragged along by his girlfriend. Most people are there to kick-start their fitness but there are two women who are training to run the marathon. I make a mental note to avoid them.

The woman with the whistle introduces herself as Cathy 'Hitler' Soraghan, the organiser. Cathy has been a personal trainer for 16 years and is not a woman you'd mess with. She points at a brunette who looks as bewildered as me. 'What's in your rucksack,' she demands.'M&Ms?' By the look on the woman's face, I think that's exactly what was in there.

The first thing about this whole exercise business is you need the right gear. Panting up a steep climb, I look at everyone else's sports jackets and walking boots and I feel like an amateur. I don't own walking boots. As for the waterproof jacket we were asked to bring, I thought I had one from an outdoor concert,but at 7am that morning I couldn't find it anywhere. Instead I had to make do with a very expensive coat that I hoped had an 'I'm sporty' hit off it - despite the shoulder pads. In the bleak light of the mountains, it really doesn't cut it.

We've been power walking for five minutes when Hitler blows the whistle. This is our cue to run. I've always liked the idea of running. It's a solitary, dignified kind of exercise and it has none of that team-spirit stuff that I hate. But that doesn't mean I've ever actually done it, so I'm surprised to find it's not as painful as expected. After five minutes, I feel invigorated, not exhausted. Then the whistle goes again and it's back to walking. After 40 minutes of this, we're by a river at the bottom of Sugar Loaf mountain and Hitler is giving a pep talk while making us do arm exerises with rubber bands.

'Forget the recession!' she orates like Robin Williams in Dead Poets Society. 'Forget gyms! You'll never feel as good as you do out in the open like this. The best things in life cost nothing, enjoy them: And she's right. We skip back in high spirits.

10AM - CIRCUIT TRAINING

NEXT up is circuits which involves running around a room doing press-ups, push-ups, squats and lunges for an hour, doing weights snd running laps in between. Apparently this kind of exercise is good because it mixes aerobic exercise with weight training. 'We're going to work your hamstrings, your biceps, your triceps, your glutimus maximus.. .' Hitler explains. 'And using weights boosts your metabolism, so that even when you stop exercising you keep burning more calories.' Cool.

But after five minutes of doing squats while lifting weights, I start to cry on the inside. After press ups with my legs cocked up on a big blow up ball, a little bit of me wants to die. Every 15 minutes or so the whistle gets blown and we have to trot down the stairs and run three laps round the courtyard. It's like being in prison. Lap one feels good. Lap two OK, Lap three - horrible. Hitler is shouting at me to go faster and I want to punch her. I hate her with a passion usually saved for siblings and call centres. And I hate myself for being so unfit. And then It rains. My misery is complete.

11AM - PILATES

IT'S only llam but I feel like I've been up for three days. It's time for Pilates, which is good because it involves lying down. It was named after its founder Joseph Pilates who developed this slow series of stretches to improve the strength and posture of ballet dancers. Apparently he used to drink so much Guinness, his wife would have to take over the lessons. My kind of man.

'It's not going to make you skinny,' says Hitler. 'But it will make you walk taller and look slimmer.' A bit like the exercise equivalent of three inch heels then. Hitler tells us that the way we live our lives hunched over computer screen is making us all walk around with our heads sticking forward. We're told that'engaging our belly buttons' which I think means suck in your tummy while breathing out, will help this.

It's hard. Within a couple of minutes our lone male has had enough. He is snoring. Literally.

Lunch

BEFORE lunch we get a nutrition lecture. I learn there are 1,000 calories in a bottle of wine. Smoothies and cereals are evil because they are full ofsugar. Coffee makes you fat by increasing levels of the stress hormone cortisol which hinders our ability to break down fat. Also, even when you lose weight fat cells stay in your body forever, just waiting for a bag of chips to make them big again. When I share my diet with her - toast with marmalade, cheese, sandwiches and pastries washed down with Rioja and lattes - she sighs. She's heard it all before.

'Do you find yourself craving caffeine and sugar fixes all the tune?' she asks. Yes. 'Do you eat a lot of bread and pasta?' Yes. 'Do you crave a glass of wine at the end of the day' Yes. She tells me that I'm a carb-aholic and that I need to go cold turkey. Lots of veg and protein she says. No bread for a while, and cut out the coffee and wine.

She may as well have told me to cut out breathing.

Lunch is vegetable soup followed by a big chicken stew and rice. I ate every last mouthful without the usual guilt. I knew my body needed it.

2PM - HIKE

It's TIME for our second hike. This time whenever we pass a big rock we have to do push-ups against it while we get lectured on our lack of upper body strength. 'We don't even do our own washing up anymore, we put everything in the dishwasher,' explains Hitler.

'We employ people to do our hoovering and mow the lawn. I'm getting men who are so flabby up top they have boobs!' I look to what our Single White Male is up to but he's vanished. Probably having a pint.

We come to a forest and are told to drop our coats on the floor and lie down on them. I hesitate. This is an expensive coat. But I'm not about to have fashion chit chat with the boss. I drop it. We're told to do 100 sit ups and by some miracle, we actually do them. Looking up at the rustling leaves and clear blue sky, I hardly feel the pain. I feel something close to happy. At peace. Could this be the exercise endorphins doing their thing?

My elation is short lived. We start to run back and in a couple of minutes we all start to flag. The whistle keeps blowing, our signal to-lift our wobbly legs from the ground, but we keep walking. Slowly. I have aching limbs, sweaty armpits and a beetroot face. Enough is enough. Hitler has a mutiny on her hands.

3PM - AB ATTACK

WE ARE introduced to a small but very heavy thing called a medicine ball, which is going to magically give us washboard tummies. We are told to get into partners and throw this lead weight at each other while doing sit ups. A stupid idea if you ask me. Annoyingly my partner thinks It's all great fun. 'This is quite easy!' she says. Cow.

Before long my middle is screaming in agony. I lie back and can't get up. No ifs or buts, (just can't. I couldn't care less if this will make me have a waist like Jessica Simpson in the good old days: Nothing is worth this pain. Nothing.

4PM - WEIGHTS

FUELLED by a bag of seeds and half a dried apricot, we move on to weights. I pick a yellow set that look pretty. I'm told off. The yellow pair is too light, the weight of a feather apparently. I need to pick up a blue pair which I do and stomp like a teenager to the back of the room. And so begins an endless cycle of lifts, curls and stretches. I'm in my own little world when I feel Hitler call my name. 'Well done Marianne,'she says. 'That's perfect!' I try to play it cool but feel ridiculously happy. Hitler loves me!

I begin to think that underneath all the fat and laziness might lie a secret fitness goddess waiting to get out. Maybe I could be one of those perfect size-eights who can wear skinny jeans with fiat shoes without putting people off their lunch...

5PM - WEIGH IN

AT THE end of the day we're given the option to be weighed and get our BMI, which is your height divided by your weight. After my weight lifting triumph I decide to feel the fear and do it anyway. I stand on the scales and try to use the power ofmy mind to levitate. It doesn't work. I'm 11st 8lbs. Exactly a stone heavier than I was the last time I weighed myself. Great. Hitler asks what height I am and I lie. I pretend I'm 5ft 8in rather than 5ft 7in in the hope that It will lower my BMI. Even with the extra inch I'm on the border between healthy and overweight. So with my true height, I'm in the unhealthy zone.

And it gets worse. Thanks to a clever little gizmo, I learn that I am 34 per cent body fat. This makes me, fat cell for fat cell, the human equivalent of a Big Mac. Usually this kind of reality check would start a spiral of self-loathing that could only be soothed with booze and chocolate, but today I laugh and shrug. I don't know if it was the endorphins or all that fresh air, but I felt like nothing can get me down. Even the 10 tonne weight that is the fat on my behind. I leave boot camp walking on air.

THE AFTERMATH

AFTER sleeping for 12 hours, I wake up the next day in agony. Even my eyelids hurt. My body was in shock. I take three paracemtomol and made a coffee. I don't care if it's making me fat. I prepare to lie on the sofa and watch TV; but couldn't settle. I feel like I'd been run over by a truck but I was full of energy. Then a strange thing happens: I start to scrub the kitchen floor. I put on the washing and power walk to the bottle bank to recycle bottles of wine from the previous week. This isn't right. I never clean or exercise.

A week on, the energy buzz has stayed. 1 walk for an hour every day and have actually chopped and eaten vegetables. I've also been in an uncharacteristically good mood. Usually when people ask me how I am, they're bored with a reluctant, 'I'm fine, you know, a bit tired, stressed.. .' Now I can see stunned expression when I reply: 'I'm great!'

I know it's premature but I really feel that bootcamp has kick-started something. The gym might make you toned, diets might make you thin, but a day of being bullied at in the Wicklow mountains will make you healthy. And more than a little bit smug. I'm in danger of becoming one of those shiny happy people that I hate. And I love it.

Cathy Soraghan's next boot camp day is on Saturday April 4 [2009] at a cost of £130, including food. Discounts for groups of more than four.