As exercise classes go, pilates appeared to be right up my street.

From what I’d seen of it on television, people appeared to spend their time lying about on mats not doing very much at all.

So, when I joined a popular class in Saltaire’s Victoria Hall, I didn’t have the usual feeling of dread as to whether I’d be able to keep up, or embarrass myself by having to sit down after ten minutes.

It turned out my preconceptions were completely wrong. True, much of the time, we did lie on mats – but, albeit slowly, we worked different parts of our bodies.

It wasn’t easy and I was surprised to find that afterwards I felt better than I had in ages – both physically and mentally.

I joined a beginner’s class run by Shipley College and led by expert Kirsten Lacey, who also teaches privately at venues across the district.

We began by spacing ourselves out on mats in one of the hall’s spacious rooms.

Kirsten starts by asking the newcomers whether we know anything about pilates, a favoured exercise of many celebrities including Madonna, Gwyneth Paltrow and Jennifer Aniston.

She goes on to explain the main difference between yoga and pilates. “The breathing techniques are different,” she says. Both focus on breathing and concentration, but yoga focuses on breathing at a deeper level. Pilates concentrates on developing the core strength inside the body and elongating the spine. Yoga is more meditative, placing emphasis on the union of body with mind and spirit.

Kirsten adds: “Pilates concentrates on posture, rather than making big movements and over-exerting yourself. You keep moving – it is slow and controlled with the focus on your posture and lower abdominals.”

Pilates concentrates on strengthening your stomach muscles and increasing the strength and flexibility of your back through gentle, slow, precise movements. This promotes improved posture and body shape and toned muscles.

“Before every exercise,” says Kirsten, “the first thing you do is pull in the lower abdominals to protect your back.”

This is harder than it sounds, yet some class members make it look a doddle. Kirsten warns against making comparisons. “Don’t worry about what other people are doing, concentrate on yourself and what is good for you.”

My back should have a little curve, and the hip and pubic bones should be level. “It is a rounded, neutral position,” says Kirsten. Mine feels more angular and skewed, but Kirsten tells me it’s not bad for a beginner.

“Locate your lower abs by taking your fingers in from the hips,” she adds. As I tried in vain to find mine, I began to wish I hadn’t eaten so much pizza and chips the night before. You certainly learn about your body in pilates, not only locating muscles, but feeling them and being aware of how they work.

We worked our way through a series of exercises involving arms and legs – all were undertaken at a slow, easy pace. Some were quite elegant, and reminded me of my eldest daughter’s ballet class.

I found certain moves, in particular a ‘chalk circle’ which involves twisting your waist, quite difficult, but Kirsten stressed that we should take things at our own pace. “It is very precise, and you must not overdo it. Don’t do anything you don’t want to do.”

Kirsten asks new class members about general health and fitness before they begin.

Mother-of-two Kirsten found that after having a Caesarean section, pilates was the only exercise that targeted her lower abdominal muscles and pelvic floor. “It is great for strength, flexibility and balance – some people find it benefits sports like skiing, and helped them to feel stable. It is good for the elderly – if you practise pilates you are less likely to slip and fall.

“It is an ideal post-natal exercise and helps improve posture. We work on pulling the shoulders back to help breathing and improve circulation.”

The gentle background music is soporific, and on more than a few occasions I felt myself drifting off.

Kirsten’s class is filled with satisfied customers – one who was amazed to find she had grown after taking up pilates.

“A general check at my doctors revealed I was taller,” says Diane Lawton, of Apperley Bridge. “It was such a surprise. I’d gone from 149cm to 153cm. I realised it must be down to my posture.”

Aminah Bhati, of Heaton, hopes the class will help her tone up after childbirth. “I hope it will strengthen my back and move the baby fat,” she says. “It is making a difference because I can feel changes.”

Wendy Atherton, of Baildon, joined the class to strengthen her muscles, to relax and to meet people. “I’m really enjoying it,” she says.

The movements increase strength and flexibility in your back – and you can really feel it. We went on to attempt the ‘pilates 100’ exercise, which involves bringing the knees up towards the chest and curling the chin down so your upper shoulders leave the mat. The legs are then straightened and held at a 40 to 60 degree angle, and the arms raised and lowered 100 times without touching the mat.

With a breathing technique thrown in, it is quite complicated, but once you grasp it, you settle into a rhythm.

“Are you feeling your lower abs?” asks Kirsten. I certainly feel something is happening – that parts of my body that have been dormant for years are waking up. On her second visit to the class, Carol Mahoney says she did not realise how tense she was before she joined. “My neck feels looser and I feel so much more relaxed.”

After 30 minutes, I did too, and the chilled-out feeling stayed with me for the next few days. As a self-confessed highly-strung, anxious person, this is the sort of exercise I should be doing regularly.

Pilates courses are at Shipley College in the daytime and evenings. For more details ring (01274) 327222 or visit shipley.ac.uk Kirsten can be contacted on (01274) 778153 or 07944 783656 or visit her website nicklacey.org.uk