I have too many running shoes for my small London flat. They are heaped in the bottom of a cupboard – 15 pairs at the last count. One or two get pulled out for a big race or a run round the park; the rest just lie there. But I won't part with them. They may look neglected, but they're all important.

I bought my first pair nine years ago. Running – exercise in general – didn't come naturally to me: at school I had a permanent note from my mum to get out of PE, and, as an adult, aerobic activity meant wild dancing in sweaty clubs. But as 30 approached I wanted to change. I wanted to run.
Running looked easy; it looked free. I'd seen people in the park, running with reckless abandon. I envied them. So I did what most exercise-shy people do and joined a gym. This way I too could run, but without the embarrassment of being watched by judgmental dog-walkers and picnickers.

But running, it turns out, was hard. Really hard. After my first wobbly attempt on a treadmill, everything hurt – not helped by my "stylish" trainers. I hadn't even realized there were different types of trainers; that the pub, aerobics class and a long-distance run might require different shoes. I soon saw a whole world of running kit open up before me. The only problem was, I didn't feel like a runner. I was just an awkward gym-goer in a Beastie Boys T-shirt and an old pair of leggings. So I made myself a deal: when I could run 5km non-stop, I'd buy myself a proper pair of running shoes.

At first I could only manage a minute or two. But strung together, those odd minutes made a mile. In time, a mile became two, and I started my blog: Lazy Girl Running. Finally the treadmill's display hit 5km. I felt proud, I felt slightly sick, and I felt ready to shop. Of course, running shoes have come a long way since then. My new shoes were big, white, ugly, and brilliantly comfy; they were what runners wore. And if I was going to be a runner, I needed to put my taste to one side and put on the uniform.

Along with their 500-odd miles, that original pair collected a lot of firsts. I wore them for my first outside run, my first 10km and, 18 months after I first stepped on the treadmill, my first half marathon. They made me a runner. In time a full marathon followed, then many more, then personal bests, triathlons, and even ultramarathons.

As I was picking up speed, so was the blog – it seems I wasn't the only lazy runner out there. It led to a book deal, The Lazy Runner, and later another on triathlons. Then I made the decision to quit my job and start again as a trainer and coach, helping people learn to love running as much as I (eventually) grew to.

When I look into that cupboard, as well as the aesthetic headway sports gear has made in the past nine years, I see memories: the trail shoes I wore for an 80km ultramarathon through Paris; the spikes, still muddy from competing in the National Cross Country Championships; and the pair that helped me to a Boston Marathon-qualifying PB after years of unsuccessful attempts – they still give me a huge confidence boost when I wear them. And all of them, worn or not, remind me of how far I've come – and that I'm a runner now.