“What’s your running goal?” says Rob Foyster, still in the consulting-room phase of my running MOT. I can’t immediately think of one, and maybe that’s the problem, but I arrive at it eventually. I want to stop giving up. I’m trapped in a cycle of getting quite competent – a half-hour 5k that doesn’t kill me, then tailing off and having to start from scratch. Laziness is like gravity: obviously I am lazy, but I think of my laziness as a constant, so it can’t explain why I sometimes run and other times don’t.

I find it hard to imagine how examining my technique will help, but that’s because I’m not imagining hard enough. Any improvement in style will make running less taxing. I start with a moderate walk along a corridor at the Ten Health and Fitness gym. My arches are fine. (But maybe yours aren’t: a lot of strain and injury, the main causes of losing your running mojo, can be prevented by orthopaedic insoles.) I do a couple of squats, a lunge and a half squat. My left side is weaker than my right, which I knew (old traffic injury, 1978!). But I did not know the degree to which this had altered the muscle balance in my right leg, so that the outer muscle was stronger than the inner, which has given me “patella maltracking”, ie my kneecap doesn’t fit congruently with the femur groove. I love the language of physios, somewhere between grammar and discos. This is why I occasionally feel like my knee will give out and never be the same again; this is also why I sometimes but not always I tail off with my regime.

Moving to the running machine, Rob takes a video from the side and from behind, whereupon it is clear that my knees are too sociable, which is to say they want to meet in the middle when they should be pointing forwards or slightly outwards. This is mainly because of the business with the patella, but also my twisty arms are making the rest of me twisty. There’s an immediate fix I can do, just by keeping my elbows in. My butt looks great, thanks for asking, and there’s no rolling in my ankles, so I don’t need better shoes.

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“If you have strength issues, or asymmetry in your strength, just being told to change your style isn’t going to work,” Rob says, which unlocks the mystery of nothing ever seeming to change (I’ve known about my wonky knees for years). Instead, I have to try specific, targeted strengthening exercises aimed at the weaker side (doing them on both sides: only doing them on one side would just heap up a load of other problems). A set of bridges, then one-legged bridges, using a resistance band; then a clam shell exercise, which is lying on one side with knees bent and opening and closing your legs like a clam.

I don’t have to stop running while I do all this; I won’t necessarily notice a difference until I’ve been doing it a few months, though. These are “biomechanic insufficiencies”, to give all this wonkiness a technical term: we all build them up if we live long enough. But it’s always possible to build them back down again.

What I learned

My cadence is 162 BPM – about average for any jogger: a marathoner would be more like 180 – and if you search 160-165 BPM on Spotify, you’ll find a load of perfect running music.