I did it - I finished the London Marathon. But I'm in some considerable pain as I write this. I don't think I would be able to ride a bicyle now even if I wanted to. 4 hours and 25 mins of constant effort is not good for you.

To spot me looking fresh as a daisy midway through the race, about to overtake a Fred Flinstone character, click here.

And please visit here to donate to Guide Dogs. I'm tantalisingly close to my fundraising target.