Running is not one sport, or one pursuit: it is dozens. From different distances to different terrains, from solo runs to group runs, from races to long slow ambles. And I love it all.

I love the relentless comforting monotony of the track session, of bashing out endless training reps of 400 or 800 or 1200 metres, of even pacing and jagged breathing. I love the broken-up toughness of a hill session – run up, jog down, repeat until fade. I love a long and steady run along the Thames, early on Sunday mornings when only dog walkers, other runners, and yet-to-go-to-bed revellers are around. I even love – or love to hate – the exhausting rolling terrain of a winter cross-country run, fingers blue with cold and losing feeling, ankle deep in sucking, chilly mud.

Why do I love it? For as many reasons as there are races. I love the clear-headed exhaustion that follows a hard run – body spent but mind miraculously clearer than the foggy-headed state I started in. I especially love the cake that follows those cross-country races. I love that running as much as I do means I can eat whatever I want – but that I don’t, because I won’t run as well if I eat nothing but cake.

I love the way runners always have excuses lined up in advance: I’m tired, I’ve not rested enough, I did a really long run yesterday, my hayfever is kicking in, I didn’t eat breakfast, my hamstring is ever so tight. Get out of jail free card thus waved, a bad race is explained, a good one is even better.

I love running because it is the most sociable of sports – anyone can do it, there are no barriers to entry, running clubs (particularly mine) are friendly and fun. Everyone has a tale to tell, a race story to unfold, advice to give. And because it is the most solitary. It’s your PB, you run for yourself, you run against yourself.

I love running at night, when the tunnel vision effect of seeing only the ground under your feet makes you feel like you are flying, even at a sedate pace. I love running across the common at twilight, when the rabbits dart out. I love being the mad person who runs in the midday sun in the hottest of heatwaves in the radiating heat of the tarmac road.

I love doing the same old runs where the route is so familiar I’ve named parts of it. I love travelling and running on new terrain. I love the stats my Garmin watch gives me, uploading, poring over last years, seeing where I stand in the injury comeback. I love ignoring the watch and just running on how I feel.

I love looking at my training schedule and seeing a really hard session. I love dreading it for days, then the fantastic feeling when I nail it anyway. I love recovery runs where the first 400m are like toppling slowly forward, your legs screaming they weren’t even going to walk, what the hell are you doing, then the slow relaxation and ease as muscles relent.

I love sprints – 100 metres where it doesn’t even hurt until you’ve finished. I love a 5k which hurts from the start and is an effort of will over common sense. I love the slower burn of a 10k, a half marathon, a marathon. I love waking up on the morning of a race and feeling sick with nerves and wondering why, exactly, I am nervous when no one but me really cares. But I love that I care enough to feel nervous.

And perhaps my ego should admit, too, that I love running because I only took it up a few years ago and turned out to be good at it. I love winning my age group, even winning the odd race. I love that my daughters want to run, because they still think I’m quite cool (yes, I know that won’t last).

But I love, simply, that I can do it. A few years ago I couldn’t reach the corner lamp-post, now there are days when I have to hold back, slow down, not do the extra miles my legs want to carry me for. I love that the human body is capable of such astonishing adaptations, that it can be pushed and pushed and still keep giving.

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