I don’t want to overshare, but it seems I also do want to overshare: I look post-lockdown terrible. My muscles are giving up from the inside. I can see the ghost of myself at 80. It doesn’t make sense on paper: I’ve run more than ever; I’ve tried live classes, some more than once; I’ve been back to the magnificent Adriene and her online yoga videos, but it appears there is just no substitute for rushing about. Only, of course, there is a substitute: if I want to recover lost muscle mass (I didn’t even know I had it until it went), I need a plan, such as a personal trainer might devise, only without a personal trainer.

Two things can go wrong, when you’re doing this on your own: a bad programme and bad technique. But, in fact, advice is tumbling over itself on how to build a programme. James Stark, founder of Starks Fitness, says it involves “a basic push-pull pattern”; for the lower body, squats, lunges, split squats. There is a near limitless variation of squats you can do if you get bored, from box squats to those with more exotic names such as cossack or Bulgarian. For the upper body, there’s the horizontal push, which is any variation on a push-up; horizontal pull exercises, which at home would most likely involve a bar, unless you have a rowing machine; and for the middle, the plank.

“We look at it through planes of motion,” Stark says – the idea that our body moves in three dimensions. It is an insanely complicated concept and involves visualising your body along three different planes, sagittal, frontal and transverse, and making sure you cover each plane. Luckily, this work has been done for you, by a gazillion personal trainers, and any given routine with three classic moves for the lower body, four for the upper, will work.

Technique is much more difficult to get right: put simply, if you’re doing anything you find easy, you’re probably doing it wrong. If you’ve been doing a lot of high-intensity training, especially trying to follow a class, you may have baked in poor technique trying to keep up. “If you’re learning a new movement,” Stark says, “you need to slow it down so you can understand and feel it correctly.” You shouldn’t be out of breath while trying to figure out a technique, he says. You shouldn’t even work yourself to the point of exhaustion, because your body learns by repetition, and if you repeatedly cut corners, that’s what it’ll learn. There’s an argument that the cardio elements – the bear crawls, star jumps – should be done at a different time, so they don’t interrupt the perfection of techniques.

The funny thing is, I always knew I was doing a press-up wrong, just by dint of being able to do it, but only in trying to relearn it from scratch did I realise that the same was true of the lunge. Really, the only thing I was doing correctly was a plank.

What I learned

If you can bear the exposure, do at least part of the programme in a park. Benches really liven things up, and a chair just isn’t the same.