I started the six-week ballet course at Xtend Barre with a robust set of prejudices, the main one being that ballet in adulthood, like other little-girl things – wearing bunches, keeping rabbits, playing netball – is a step past nostalgia towards fetish. Plus, I did ballet when I was a kid and hated it.

The sheer preposterousness of it, galumphing great adults (that’s unfair, only I galumph) doing pointy toes: how do you get past that? But there’s something engrossing, even dreamlike about it. I came out after an hour feeling as though I’d just been hypnotised.

Barre work is like the Lego of exercise, blocks planted on blocks, five foot positions (helpfully labelled first to fifth), five arm positions (brava, then second to fifth), four basic leg moves (tendu, degage, grand battement, plié), then front, side, back. You build them into exercises – a tendu from first position (pointy toes slid along the floor), a degage from third (toe slid and lifted), a plié from second (like a squat only straight backed, arse not sticking out), many times. It’s repetitive, precise and mesmeric. It’s whole-body taxing but breaks no sweat. The class is about 10-strong and an air of prim competitiveness pervades, everyone checking one another for neatness. There are no tutus, just standard Pilates-chic cropped leggings and barre socks.

You can see yourself in a mirror from every wall, as unlike a ballerina as a bricklayer is to a stonemason, and yet it is so pleasing – a sense of perpetual improvement, body beset by abstruse protocols, hands faking limpness but elaborately curved, chin up, back erect and proper as if you’ve just been insulted. There’s a lot of smiling. You don’t get that in an aerobics class – “smile, ladies”.

But I didn’t mind it. When you’re a kid, they play you twangly Bach; when you’re an adult, you get instrumental versions of Beyoncé hits. Again, didn’t mind it. Don’t know why. In a shopping centre, it would drive me bananas.

The barre is half of the class, then you move to the centre of the room, where the lack of a balancing aid combines with more difficult manoeuvres. The arabesque, one leg elegantly (in theory) lifted behind you, the pirouette, for which you must choose a spot on the wall and fix upon it with your eyes, turning your head at the last possible moment.

I’m three weeks in now, and I feel minusculey better at everything, but none of it makes me ache the next day. It wasn’t devised for exercise, it was devised for beauty. Modern life has repurposed it for strength and conditioning, which must be true – you definitely use your muscles – but it’s not as bracing as Pilates. I think you have to believe in the beauty of the human form to commit to it. So far, I move like a fireman trying to get a wasp out of my boot.

This week I learned

Ballet will help if you are looking for extra poise, but doesn’t have the same benefits as a Pilates session