It is traditional in January for newspapers to run articles about diet and health, so I thought I would write about the healthy subject of physical exercise and my long-running unhealthy relationship with it. There are two ways to be unhealthy about exercise: you can avoid it, or you can be obsessive about it. And because I’m the kind of person who likes to do things properly, in my life I’ve covered both bases.

As a kid, I loathed PE, and I used to tell myself that was because I simply didn’t enjoy it. In reality, it was because I wasn’t good at it and, as a precocious perfectionist, if I couldn’t do something well, I simply wouldn’t do it. Some of my most vivid memories from school involve PE teachers singling me out and making me run/hit a ball/jump to show the rest of the class how not to do it.

I was the “before” photo of PE, while my athletic best friend was invariably the “after”. Thus began the long years of increasingly elaborate lies (“A lot of 11-year-olds get three periods a month”) in order to avoid exercise. Then I turned 13 and suddenly became obsessed with being skinny. Exercise no longer seemed a problem but a solution to a problem that didn’t actually exist. I went to aerobics classes at the gym on our local high street, where I was about a third of the age of everyone else; I sometimes wonder if any of them thought it odd that a little girl who didn’t even need a bra was in a bums, tums and thighs class. Daily, I would do hundreds of sit-ups and star jumps in my room, making the whole house shake with my newfound athleticism, high on the idea of how many calories I was burning. This went on for years, and I guess you could say I was finally getting something out of exercise, though I wouldn’t describe it as beneficial.

When I finally shook that in my early 20s, I reverted to my default position of avoiding exercise in the (not unreasonable) belief that a recovering anorexic couldn’t be trusted with it, any more than an alcoholic should sniff a bottle of whisky. But the real problem was I had never learned to think of exercise as something one might do simply because it’s fun: either it had to be for an end goal (being thin), or you had to be good at it. If you’re bad at something, it couldn’t ever be enjoyable, right? But at some point in my mid-20s I realised that I needed to do something other than sit in a chair all day, so I asked a friend for advice. “Have you tried yoga?” she asked.

In the US and UK, yoga has an extremely annoying image – one of thin women with long, lean limbs, who subsist on seaweed salad and oat milk. It’s exercise for Gwyneth Paltrow wannabes. And precisely because of that image, I signed up immediately, because while I was no longer doing sit-ups in my bedroom, some deluded fantasies take longer to die and mental illness is tenacious.

So I went to my first yoga lesson and quickly realised that I did not have a natural gift for it. I despaired at my inflexibility, my wonkily-shaped feet, my terror of going upside down. I was easily the worst in the class. Even the overweight 60-year-old men who had come on doctor’s orders were better than me.

And yet I kept going, twice a week, every week. It would be a lie to claim there wasn’t, initially, an obsessive element to this. But at a certain point I realised that, actually, yoga doesn’t make you thin. Not even the dynamic classes I go to (because the slow classes literally send me to sleep). But yoga made me feel strong and flexible, two things I had never before felt in my life, physically or metaphorically. And so I continued to go.

I’ve now been doing yoga for, I think, 14 years and lest any images of me doing elegant backbends are dancing through your head, let me reassure you, I am still terrible. While everyone in my class is springing effortlessly into a handstand, I remain stubbornly grounded. But I don’t care. My ludicrously patient teacher (namaste, Stewart Gilchrist at East London School of Yoga!) ensures I make just enough progress every week to stay excited (I can touch my toes! I’m basically an Olympian!). He never singles me out as an example of how not to do something, even though I am, and he reassures me that just because something is hard it doesn’t mean you can’t do it. After all, he says, you learn how to do something only by making mistakes; no one is judging you but you. These are lessons that I have – as yoga teachers say – “taken off my mat” and applied to my daily life.

That I make time every week to do exercise that (a) won’t make me thinner and (b) I’m embarrassingly bad at, is as shocking to me as the fact I can now eat for pleasure. The two are linked, of course, and maybe I would have got here eventually anyway. But yoga helped me on my way. And for that reason I will always be grateful to it, Gwyneth schmyneth.