My London Marathon countdown calculator (aka the Top Gear calendar I bought from Sainsbury’s for two quid last week) reliably informs me that I have 93 days left until the big day.

That means only 93 more days of waking up every morning questioning why, 93 days of counting calories - my Dad would be so ashamed if he knew - and 93 days of people looking surprised and saying "really, you?" when informed that all 14 ½ stone of me will be participating in the world’s most famous race in April.

I feel at this stage it would probably be polite to introduce myself. My name is Mark Lomas and I’m a 23-year-old sports journalist who, aside from the increasingly occasional Didier Drogba-esque display at five-a-side, will simply never be considered an athlete. Having received confirmation that I will be joining Teletubbies, deep-sea divers and thousands of other novelty-costumed folk in running 26.2 miles, I have been training for almost six weeks now.

Annoyingly - mainly because so many friends and colleagues told me it would be the case - the first three of those were made pretty much redundant by an over-indulgent Christmas filled with mince pies, M&S (okay, Lidl) festive treats, copious amounts of lager and approximately no running.

January was supposed to bring with it a new year and a new start, but after nursing hangovers on both the first and second days of 2011, my first exercise-related outing was not until the third. Now, I must stress that really am extremely motivated to run the marathon, but creating a training plan is simply something I haven’t got round to. I have been loosely (and I use the term loosely...well, loosely) aiming for two short runs and one long run a week but there are no set days because my I work shifts and I don’t want my social life to play the role of sacrificial lamb.

Despite these limits to my training, there is a positive on the horizon as I am planning to get myself a shiny new pair of actual running shoes this week. Like Rolling Stone Keith Richards, my seven-year-old Reeboks are still full of character, but having been round the block a bit have lost their once appealing exterior. Unlike the rock legend, though, they will now bow out gracefully, with their impending retirement to the big shoebox in the sky serving to fill me with misplaced belief that my new trainers will a) make me look better and b) make me train harder. Well, Oscar Wilde did once say that the basis of optimism is sheer terror.

Mark Lomas is a sports journalist working for ESPNsoccernet in Hammersmith. On April 17th he will be running the London Marathon for Heart Research UK and for the next 12 weeks will be delivering a blisters and all weekly update on his training regime. He can be sponsored for his efforts at http://uk.virginmoneygiving.com/MarkLomas