Don't ask me why but I've accepted the Shelter Vertical Rush challenge to race up the 920 steps (42 storeys) of Tower 42 in the City of London (formerly the Natwest Tower).

OK this is not quite as impressive as a marathon but what will be impressive is that I'll be away from Twitter for well over 30mins which is far more impressive than running a marathon in my case.

So yes, I'm basically asking you to give me money to not use Twitter for an hour.