I’ve been going to Pilates classes for about ten years, on and off. Ten years ago I was working in a bookshop with a specialist line in what those in the business call “Mind, Body and Spirit”, though I can think of a few other names for it.

Sometimes, people would come to the shop and try to sell us books. One day, a man who looked a bit like God came in and tried to persuade us to buy twenty copies of his book about Pilates. Neither I nor the boss knew what Pilates was and so he gave us a thirty-minute lecture, after which we ungratefully didn’t buy the book (books about exercise regimes were already a bit old hat, even in those days of dial-up internet). But my curiosity was piqued and a short time afterwards I signed up for classes at Brockwell Lido.

Pilates suits me. I am quite bendy, so I get to feel as though I’m doing well at it right from the start – something which never happens to me with most forms of exercise. Plus, I like to do something where I have to be very intent and focused in the moment, rather than something like running or swimming which you can do mindlessly whilst still thinking about work and worrying about the gas bill. If you work hard at Pilates, there is no time or space to be doing anything other than Pilates, and being able to tune out of real life for an hour is a rare and valuable thing.

And then, the more you do of it, the better your posture is and the less likely you are to injure yourself in the course of other types of exercise, and those are both good things too.

However, there is a small price to pay for all these benefits, and that comes in the shape of other people. Sometimes the other people in a Pilates class are fine. A lot of the time, they are a nightmare. Imagine the scene: you are lying on your back with your eyes closed, your arms at your side, your knees bent, your abdominal muscles engaged and your pelvis in a neutral position, focusing on your breathing. Your mind begins to go blank as you become as one with your body and the day’s stresses and minor inconveniences recede into the background. And then someone in the corner pipes up:

“Excuse me, should I be feeling this in my hamstrings? I’ve got an old shoulder injury, should I do this differently? Do you like my tight lycra pants? Gosh, I’m annoying, aren’t I?”

These are the people who see Pilates not as a much-needed respite from the rush of the working day or a way to improve their health and physical fitness, but as a competitive sport in which the challenge is to work hardest and bend furthest, and the prize is to get more attention from the instructor than anyone else does.

Here’s the thing. No Pilates instructor worthy of the name will start a class without checking whether anyone in that class is injured, or pregnant. If you are either of those things, she will be aware of it and will let you know if you need to do anything differently from the rest of the class. Otherwise, Pilates is not an impact sport; you don’t have to be able to do it faster than anyone else, and you should probably just shut up so that everyone else in the room can carry on with the class, rather than sitting around waiting for the instructor, who is too polite to tell you to shut up, to come up with an answer to your inane question.

So here are my simple rules for attending a Pilates class. (They work for yoga too.)

1. Tell the instructor in advance if you are injured or pregnant. (If you are both, consider whether you ought to be at a Pilates class. Some days it really is a better idea just to lie down and eat chocolate.)
2. Save your questions for the end. You are paying for the instructor’s time, but you are paying to share it with fifteen other people. If the answer to your question is not going to interest them, ask it afterwards.
3. Good grief, breathe normally! There is no award for effort for the person who sounds most like Ivor the Engine on each exhalation. It is both possible and desirable to breathe out through your mouth without sounding like an elephant. I don’t want to hear your breath any more than I want to smell it.
4. A tricky one this: try not to fart too close to anyone’s face. I know you can’t always help it. But, you know, I can manage it, so it technically possible. That’s all I’m saying.
5. Talking of which: when the instructor tells you to swing your arms out to the side, do check that you’re not about to hit someone over the head before you do it. It’s so much easier and more elegant than having to apologise afterwards.

There. Just five rules, but you will find that your experience, and those of the people around you, is wonderfully enhanced by following them.

My sixth personal rule is “remember to get changed back into your work clothes after the class and before leaving work”. Since I am still sitting here in my tracksuit bottoms and hoodie* I will now go and obey that rule. Laters.

*the hoodie is actually also part of my work clothes, but there should be a dress under it rather than a vest.