What is it? A vest – with weights in it – that you wear during workouts.

How much does it cost? Mine (the 14kg Authentic RDX Pro Weighted Flex Jacket) costs £26, but such vests can cost up to £350.

What does it promise? Theoretically, it will help you to train harder. You’re dragging around extra weight, so you’ll encounter much more resistance than you would in normal training.

What’s it actually like? It varies. At first I used mine for stuff like press-ups and pull-ups, and it was great – it made things slightly harder, but not impossible. After that, I decided to hit the streets. This was an error. Not only did the vest slow me down considerably, but I found myself fully exhausted less than a kilometre into what was supposed to be a 5k run. I’d just climbed an especially steep hill, and ended up having something of a volcanic meltdown. My heart felt as if it was going to burst, and all I wanted to do was take off the vest. But I couldn’t, because I’d still have had to carry the poxy thing home anyway. So I walked home in it, full of hatred.

Best and worst bit The best bit is the way you look as if you’re wearing a bulletproof vest whenever you go out in it. The worst part is the exhaustion. Remember how close to death you felt after running for a bus before you started exercising? This is how a weighted vest will make you feel all the time.

Is it worth it? For regular floor workouts, yes. For running on a treadmill, yes. For going outside in, dear God, no.