The alarm goes off at 4.30 in the morning. I'm awake straight away, with that mix of nerves and excitement you can feel in your stomach. Today I'm going to try to run 100 kilometres without stopping. That's 62 miles.
The furthest I've ever run in one day is 36 miles. Today is that again, with another marathon on the end.
I'd love to say I'm ready. I'm not. Most of my runs this year have been short, and there haven't been many of them. I'm counting on my base fitness to get me round.
Missing the start
I get to the start line with a three-litre tank on my back, full of beetroot, pineapple and celery juice, mixed with water and a pinch of Himalayan salt.
Then I miss the official start, because I'm still queuing for one last toilet stop.
The first mile is slow. I'm stuck behind walkers, there are queues at the gates, and I'm weaving through the crowd. Early on I bump into a friend and we run together for a while, which helps the miles go.
The trail is beautiful. Woods, corn fields, a stretch along the Thames, open countryside. It's also hot, properly hot, which is lovely on a beach and miserable on mile twenty. I'm quietly hoping for a shower of rain. The only thing getting me wet is my own sweat.
Halfway
After eight and a half hours I reach the halfway point. I eat a meal, check my feet and change my socks. My feet are holding up, which feels like a small miracle.
Looking back, I stayed in that pit stop too long. By the time I'm moving properly again, the sun is starting to go down.
Into the dark
This is where it gets interesting. I've passed 36 miles, so every step from here is further than I've ever been. I've got no idea whether my body will hold out. I've decided that only a proper injury is stopping me.
As it gets dark I swap my sunglasses for a head torch. The chalk trail turns into a blur of white. The big stones hurt every time I land on one, and the grass paths just disappear into the dark.
I can either look ahead to see where I'm going, or look down to see where I'm putting my feet. With 20 kilometres left I'm desperate to run and I simply can't see well enough. So I walk, slowly and carefully, on very sore feet.
The only running I manage at the end is under the floodlights near the finish. Nineteen hours after I set off, I've covered more than 63 miles and there's a medal round my neck. My feet are wrecked, and it is completely worth it.
What the dark bit taught me
That was the summer of 2015. Earlier that year I'd run my dad's half marathon in Southampton. The 100 kilometres was something else entirely.
Distance running is a decent picture of life. There are hills to climb, and stretches where you're running with other people and stretches where you're on your own. Some miles feel easy. Some feel impossible.
What stays with me most is the dark part. I couldn't run, so I didn't. I walked, and I kept going, and walking still got me to the finish. I wrote about the rest of what running taught me in What marathon training taught me about big goals.
If you're in a dark stretch right now, on a goal or anything else, give yourself permission to slow down. Pick the next small marker you can actually see, and walk to that one. You can run again once the lights come back on.
First published July 2015.
