Posture: Will this top make you sit up straight? Corset will!

The new Core range vest from Pelham & Strutt

You may be sitting comfortably but if, like me, you have the muscle tone of a jellyfish and physical comportment that's more Royle Family than Royal Ballet, you probably also have bad posture.

No more, comes the promise from the makers of a new vest that has, for the past 10 hours, rendered me almost breathless but also strangely upright.

The Core range from London outfit Pelham & Strutt comes with jargon ("biological expertise delivers a range of intelligent underwear known as corepression") and a warning: "Adding this to your daily routine can make you dangerously attractive. Wear with caution."

I ask Gillian, my dangerously honest deskmate, whether my new vest, worn under an old jumper, is having the promised effect. "I feel sick," she replies.

Fair enough. But how does it make me feel? Squeezed. Off, the T-shirt looks way smaller than the large I ordered. Getting into it would be easier with disjointed shoulders. Apart from being unforgivingly tight, the shirt includes elastic panels ("physiotherapy integrated mapping") designed to pull back the shoulders and contract the abdomen in a way that does feel like it's straightening my spine. It also makes my arms hang way out from my sides in the manner of a rich man in a tailored suit (think Daniel Craig or Tony Blair giving it the full statesman).

Like similar compressionwear increasingly marketed to men (Spanx for Men, Equmen, George at Asda's Bodysculpt range), the T-shirt also promises to trim inches from my torso. It does, but in the way tight corsetry made ladies' waists small back in the day: it's a tad uncomfortable (pass the smelling salts). And if, like the models in the literature, you don't already have perfect posture and a six-pack, the shirt also causes what Pelham & Strutt probably wouldn't call bulge displacement.

There's no doubt that I'm slouching less but, regardless of any proposed effects on my attractiveness, I suspect I won't rush again to wear what is effectively a £50 corset (that's if I can even get it off without calling the fire brigade).