Fighting fit and deeply cleansed

So as my 50th birthday loomed, I decided to get fit not fat. It doesn't bother me about being 50 – it's better than the alternative – but I want to be as healthy as possible. I have twin 11-year-old sons and I owe it to them and myself to keep well.

So, having done my research, I opted to do a week at The Camp. It's the original boot camp in the UK, solely for women and its instructors are ex-Army and Special Forces instructors so in for a penny in for a (soon to be lost) pound.

I was one of 21 women who gathered nervously as The Camp's co-founder, a very dashing ex-Major Sebastian Morley – think Colin Firth does military, ladies – introduced his team.

Clad in super-shiny Army boots and combat trousers, Euan, Bobby, Grahame and Billy looked scary as they listed their impressive fitness qualifications. We ranged from mid-30s to early 60s, and of differing weights and fitness levels – and age was no indication to fitness as the oldest in the group was fitter than some women 20 years her junior.

It was explained that we would eat between 1,400 and

1600 calories a day, designed to include all the nutrients we need, and would be doing 5,000Kcals of exercise a day.

We were weighed and measured and then shown how to do the exercises we'd do day in, day out for the week.

The group was halved according to fitness levels and Sunday we were woken at 5.45am – yes, that's right – to begin exercise at 6am. Come hail, rain or shine, we were out in the fresh air doing 45 minutes of squats, dips, jogs and sit-ups.

A gruelling 13-hour day followed, including a two-hour hike across rough Scottish hillsides in sheeting rain. Some of the women, who had done no exercise for years, found it a tough start.

But they didn't give up. Just 24 hours after meeting the team, I was plotting to bury them alive – but was too tired to think my plan through. After a small evening meal, we finished the day with 45 minutes of exercise using a fitness ball and boxercise – which I came to love. By Wednesday, as I saw glimmers of my waist and jaw line reappearing, I began

to feel the benefits of the exercise and controlled meal portions. Most mornings post-breakfast we'd do a trim trail – exercise in the 300 acres of wooded countryside surrounding the house before embarking on that day's venture.

As the week progressed, our team really bonded amid black humour as we gave our best shot at whatever was thrown at us. I no longer wanted to bury alive the instructors as I was so impressed with their knowledge and organisational skills and, however tough some of us found it, they were always so encouraging.

The toughest two days were towards the end of the week. We climbed to the 711m summit of Cairnsmore in five hours. Some women overcame fears of water or heights to achieve tasks. My shining moment was abseiling down a 100ft rock side.

I could hear my heart beating as I edged over the top, eased down a few feet before losing my grip and crashing into the rock side.

I earned Sebastian's praise as I righted myself – "epic, Sheron, epic", he called. Never been called that before, I thought as I laid back 90 degrees and made my way to the ground.

As the week finished, I felt so much fitter. I'd lost 5lb, two inches from my waist and an inch from my hips while increasing my muscle by 1.5 per cent.

As one woman suddenly announced, if it wasn't unprofessional, we'd have kissed the guys!

Weight loss varied between four and nine pounds, inch loss was also great. But what was even better was the feeling of accomplishment we all had from doing tasks we'd have never thought we could.

My boys think I am cool now because I river walked, abseiled and spent the week "with the SAS". I think I am cool because I might not have been the fastest, fittest or most agile – but I did my best and did it all.

As I drove home, I reflected on the week.

Though it is dearer than

the normal week's break, you do not spend anything during your stay; in fact you never use a handbag.

It was the longest most of us had left our families, work and the demands of busy life – just to concentrate on ourselves.

For more details on the course, see www.thecamp.co.uk or 0800 335 7672.