A man who lost more than 10 stone (63.5kg) in nine months is planning to run in this year's London Marathon.
He aims to complete the marathon in under five hours
Martin Higson, 47, who lives near Lichfield, Staffordshire, and in Rugby, Warwickshire, weighed nearly 26 stone (165kg) at the start of last year.
Mr Higson said: "You just wonder how you can actually get yourself into that position."
Mr Higson was a finalist in the Cambridge Diet Slimmer of the Year competition in December.
He said he just sees a "mess" when looking at an old photograph, adding: "There is actually somebody that I don't even recognise."
His transformation has been put down to hard work, with no surgery or medication involved.
Mr Higson added: "I'm trying to go and do the marathon in under five hours, but after that maybe (I will do) half marathons where the training's not quite so long and intense."