This time last year, I laced up my trainers and went for a run; the first run I had been on since my childhood. It hurt. After running (well, jogging) and walking for about 2 miles, I collapsed on my doorstep for 20 minutes to recover.

It's got slightly easier since then. I spent 2012 progressing through 10k races and completing my first half marathon, before foolishly accepting a place at the Virgin London Marathon 2013 on behalf of the Jigsaw Trust.

What followed was a long, cold, dark winter of marathon training. A month before the London Marathon I nailed a 21 mile road race in just under three hours and then, on the big day itself, just about held it together to finish my first ever marathon in 3 hours 39 minutes 15 seconds.

In the space of a year, I had gone from non-runner to marathon runner. That felt good. It also felt good to be able to raise £1,750 for the Jigsaw Trust in the process.

Always looking for a new challenge, I picked the Greensand Marathon because a) it's near my house, b) I like trail running, and c) it's been described as one of the toughest marathons in England.

What makes the Greensand so tough? Well, in addition to the small matter of running 26.2 miles, the course involves a vertical mile of climbing.That's higher than the tallest mountain in England.

The sadistic race organisers have also thrown in a cut-off time for reaching the quarter way point at Leith Hill.

This is a marathon which starts with a mass singing of Jeruselem. Bring me my Chariot of fire!, indeed.

Between now and October I need to become a mountain goat. The hills have to become my home. This isn't a marathon I can hope to complete by simply turning up on the day and pushing my body to the absolute limits (although that will also be necessary).

Ahead of the Greensand Marathon in October, I've picked a couple of tough trail races to get some race specific practice. The Surrey Badger Half Marathon in July and Hard as Snails 10k in September should hopefully both remind me what torture lies ahead.

Once again, I'm aiming to raise funds for the Jigsaw Trust. The Greensand Marathon might not have the same mass appeal of the London Marathon, but trust me when I say you will enjoy watching me suffer, during training and on the race day itself.

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