Three years ago today, I ran the London Marathon. You have to have known me for a long time to know how very unusual and surprising that was for me. I was one of those kids at school who used to sneak off to the bus during cross-country running. During my student years, friends would joke that I’d get a taxi home from their houses rather than walk the 200 yards back to my flat. In my 30s, I’d look upon those people who would get up on a Sunday morning and ‘go for a run,’ with awe and wonder, certain they must be an entirely different species to me.

I started running during my first years as a single parent, driven by anxious energy and a need to keep moving to burn away sadness and fear and worry. It was something I could do on those days when my baby son had gone to stay with his dad and I had no idea what to do with myself. I’d set off down the Fallowfield Loop in my baggy Miss Selfridge leggings and an elderly T-Shirt, unencumbered by a pram and a nappy bag and all the other baby paraphernalia I was used to lugging around and I’d just run. So slowly, I must have looked quite strange. I’d go as far as I could go and for as long as I could manage and it utterly transformed me. I learned there was something I could actually do that would make me feel better, something as simple as putting one foot in front of the other.

When I was offered, through work, a place on the London Marathon, although it was only 8 weeks or so away and although I’d only been used to running around 10k at that time, I leapt at the chance. I was thinking about the day itself, the race and the finish. I was, above all, amused and tickled pink that I had become someone who might undertake a challenge like this. I, me, new me.

I hadn’t really anticipated the training – the hours and hours I’d have to spend pounding the streets of South Manchester in the dark and the rain after work on, say, a Tuesday night, or what the difference between 10k and 10 miles would feel like to my shell-shocked feet. People warned me to go easy; I could hurt myself. People muttered about ‘the wall’: the point at which runners say they hit a block they can’t get past. I was probably too naïve and inexperienced to pay it any mind. If I just refused to engage with the idea of a wall, I reasoned, then there would be no wall.

And I did it! And it was incredible. I took the advice of a colleague and wore a vest with my name on it, not really understanding why until I heard strangers cheering me on – me, personally, among thousands of others – from the sidelines. And there was no wall, though this might have had a lot to do with the speed in which I did it. The only goal I had set myself was to keep running, however slowly, and to finish. It took me the best part of five hours. When I realised I was being overtaken at one point by the man with the fridge on his back, I set myself a new goal: don’t, whatever you do, let the man with the fridge on his back beat you to the finish line.

I liked to tell people afterwards that it had been easy and in many ways it was. Much easier, in any case, than the other challenges I had faced in my life. There was nothing at stake. There was cheering from the sidelines. And all I’d had to do, after all, was put one foot in front of the other.

In his book What I Talk About When I Talk About Running, the novelist Haruki Murakami draws a parallel between running and writing. He writes of the need, with both, for focus and endurance:

‘One foot in front of the other. Repeat as often as necessary to finish.’

As simple as that. But I think it’s Neil Gaiman, in the advice he gives to writers, who really has it right:

‘This is how you do it: you sit down at the keyboard and you put one word after another until it’s done. It’s that easy … and that hard.’

I’ve thought of this advice a lot this week. As I near the end of my fourth month of writing and publishing new work every day, putting one foot in front of the other, one word after another, is starting to feel very hard. This week I’ve started a new job – a very exciting one – and my son went back to school, and I’m in the process of applying for a mortgage … and my car failed its MOT. And I’m tired. I have written more words than I would like to have written about how hard it is to write words! I worry I might never be able to find more than this to say. The outline of a wall has started to take shape ahead of me and I am working hard every day to push it away in the hope that if I just refuse to engage with the idea of a wall, then there will be no wall.

So I will keep on keeping on. And when in doubt, I’ll remember how it felt to cross the finish line on The Mall. I’ll remember biting into the juicy apple I found in my goodie bag and I’ll think of the knowledge I gained. I send my very best to everyone that ran today. It’s easy, really, isn’t it? And hard. Be proud.

I’m writing to raise money for Shelter. You can donate here: https://www.justgiving.com/fundraising/drivinginthedark