I decided to go to trampoline circuits, just for the craic – I’m way past “Make your peace with the new normal”, I want as many new, weird things to happen as possible. I am past caring about whether or not I’ve maximised every workout minute (though, it turns out, on a trampoline I seriously did).

So, there’s one overridingly relevant thing about trampolining in your 40s, and there is nobody who doesn’t mention it. “I hope you’ve got your tenners,” my friend said as I set off, and I replied, “It’s really not that expensive, Wandsworth Flip Out is only seven quid.” Except she meant Tena incontinence pads, and cycled off saying “I love the fact you think it isn’t going to happen to you!” And she was right, I didn’t, because why on earth would anyone wet themselves on a trampoline? Except, apparently, everyone does. Just bookmark that thought for the time being.

This is a real couples’, or mates’, exercise; of the 12 of us, only two were on our own, and we were the same two who weren’t bouncing very high, as the others plainly did this every week. The format is simple: four circuits of three exercises, each for 30 seconds with a 30-second break. Very efficient: warmup, eight minutes a circuit, warm down, bam, you’re done. There’s no time, really, to think, which often doesn’t matter. A star jump, a stomach crunch, a press-up (against the side of the trampoline), some very high jumping; none of this needs deep intellectual engagement, it’s just like doing it on the ground, except infinitely more fun.

Other moves are more complicated – the squat, for instance, is quite tricky on a trampoline, being a resistance move. And you can’t really copy anyone, not even the instructor; you have to figure out for yourself how to maintain momentum. The unstable surface forces you to concentrate, so you notice your exhaustion less.

And it is a wildly good workout. I take my Fitbit with a pinch of salt, since it frequently claims I’ve smashed my day’s fitness goal when all I’ve done is a circuit of Lidl, but these stats were unarguable. It was, according to my heart, the longest consistent period of intense activity I’ve done – 70 minutes in the cardio or fat-burning zones – which, considering the class was only 45mins long, was some going. Afterwards, I was indulging in mad schemes of how I could come more often, maybe by pretending the children were 14 and forcing them to come with me.

In answer to the continence question, it really isn’t as bad as people say: maybe things were a bit dicey during a star jump, but no worse than your average sneeze. I can see this is way too much information, unless you’re thinking of trying trampolining yourself, in which case it is not enough.

What I learned

The energy consumption is simliar to moderate running, but studies show the rate of perceived exertion to be lower. Probably because it’s so much fun.