Nearly two weeks ago I got the news that a friend of mine had died, suddenly, in a snowboarding accident in Chamonix. John was supposed to be returning the next day. He and I were going to go running when I was in Edinburgh in August. We were going to go swimming in the North Sea. John was 34.

John emailed me a couple of weeks ago when I signed up to the marathon with a brilliant, detailed training regime. I even started following bits of it.

And now he's gone. He was a brilliant, generous, kind and tough man.

He was also an active, extremely sporty person as I knew him. The prospect of MS was an incredibly difficult thing for him to deal with. I remember him saying Young MS Sufferers groups were really helping him. That's why this charity. That's why you should support it. And me. For him.

The second I heard the news, there really was nothing else better I could do for him than run this marathon.

He would have been proud. Then he would have said 'next time, faster', and showed me how.

26.2 miles through the Lake District. Not just a marathon. One with hills. And dirt. And mud. Run by a swimmer from the flatlands of Lincolnshire. Bring it.

I miss you, John.