The Gyrotonic Expansion Machine could be something from the dark ages but it is the key to long, lean muscles and good posture.

It looks like a medieval instrument of torture with its weights, ropes, pullies and straps. But this training machine is taking the celebrity world by storm.

Madonna, Gwyneth Paltrow, Kim Cattrall and Julianne Moore are all reportedly using it as a way of keeping fit. So I decided to discover the secret to their lean, flexible limbs and perfect posture by getting strapped in myself.

When faced with Laurie Booth's Gyrotonic Machine at Brighton Natural Health Centre, Regent Street, I couldn't help feeling a bit worried about what was in store.

But those who are afraid of gym weights need not fear. Although it looks scary - and it does put you through your paces - I found it to be surprisingly gentle on my body.

During my session Laurie took me through a range of exercises which focused on different muscles and parts of my body by altering the set-up of the machine. I stretched and twisted, pulled and pushed my way through what Laurie described as a series of supportive shapes.

My legs were put in stirrups and I rotated them round and moved them up and down. Then, with my arms in stirrups or holding a bar or handles I bent backwards and forwards.

All the while Laurie guided my movements so they were performed properly and corrected my posture so that my back - which is usually hunched over a desk - was adjusted and straightened.

Although I felt like I was working out there was no pain or over-exhaustion. And when Laurie and his machine had finished working their magic I left the building walking tall and proud.

The Gyrotonic machine was the brainchild of Romanian ballet dancer Julio Horvarth. The son of a carpenter who had learned skills from his father, he developed the system of pullies and weights in the late Seventies and early Eighties as a way of dealing with the injuries he had suffered as a dancer.

Laurie, 50, is an award-winning choreographer and dancer himself. He has been using the Gyrotonic machine for ten years and has been teaching it since 1998.

Gyrotonic features principles of dance, martial arts, yoga and swimming. It also has some similarities to pilates as it works on the core stabilising muscles.

These muscles, which lie deep within our body and don't always get touched by exercise, are constantly engaged in a Gyrotonic work-out. The machine reached parts I didn't even know I had.

It re-educates the way your body moves and is intended to give you better posture. It made me more aware of how I hold myself and I still frequently find myself readjusting my stance.

"It is almost re-programming your bodies software and drawing attention to areas of activity or inactivity in the body," Laurie says.

"We are living in an environment which is increasingly driving us away from the proper use of the body. Many people use cars and many people sit at computers. The body is fitted into a hostile environment."

Rather than giving you big, bulging muscles it makes them long and lean yet still strong. It can focus on specific muscles and even strengthens the tiny micro-muscle tissues and ligaments.

It also turns up the body's metabolism thermostat which will allow you to burn more calories.

Laurie's students include dancers, MS sufferers, barristers, people who also see osteopaths, pilates and yoga instructors looking for a way of extending their work, office workers suffering from problems with their upper backs and even a couple in their 60s.

Most people visit him once a week, sometimes twice. Many of his clients have been seeing him for at least a year now.

Laurie says: "Most people get seriously addicted to it. There are hundreds of things you can do with the machine - it is very creative. Every day is a new sensation."

A hour session costs £25 or £20 for students. You can book a block of ten sessions in six weeks for £200.

Call Laurie on 07788 592817 or email gyrotonic@mac.com. Log on to www.gyrotonic.com for more information about Gyrotonic Expansion.