"As a young boy growing up in London it has always been my ambition to run the London Marathon," he said after competing in Birmingham on Saturday. "I won the mini marathon when I was younger and have watched the race every year for as long as I can remember."
On the start line with Farah will be the marathon world record holder Patrick Makau, the Olympic champion Stephen Kiprotich and the world champion Abel Kirui, as well as the reigning London champion Wilson Kipsang and the course record holder Emmanuel Mutai.
Asked if he might be tempted to change his mind mid-race and go the full distance, Farah said: "No, there's no chance. I have a plan to go to halfway and that will be it – even if I'm tempted to finish, even if I feel great. My plan's just to run the half, get good experience and look forward to 2014."
This will be the first time that the London Marathon has ever offered an athlete the chance to run a half-marathon as part of its race, a distance in which Farah already holds the British record after debuting in New York in 2011, and recording a victory of 60min 23sec.
Running a full marathon in a world championships year – with Farah desperate to win the 10,000m title he lost out to by just 0.29 in Daegu, as well as defend his 5,000m title – would have been too physically demanding but still his halfway house solution has left him open to criticism.
Paula Radcliffe, who set the women's marathon world record on the course, questioned Farah's decision to run only half of the race. Radcliffe, who has been a mentor to the athlete since his junior days, told the BBC: "Honestly, I find it a little bit strange – it's not what I would have done. Either you find a good half-marathon somewhere or you take the plunge and attack the distance and race it. Here he's caught between two stools. For me, you go into the London Marathon when you're ready to do it and attack it hard. But everybody has different reasons."
Asked whether his strategy was "strange", Farah shook his head. "Not at all. I think practice makes perfect. The more practice you do the better chance of getting it right. It's not just about running in the marathon. It's about dealing with everything – making sure you've got the carbs the night before. Getting up and going on the bus to the start. It's going to be perfect practice."
Farah said he is looking forward to running among the London crowds along part of the 26.2 mile route which will be lined by 650,000 people. "Running in the London Olympics, having 75,000 people [80,000] cheering for you … that was the best thing ever. I just get excited about the amount of people who can come out on the marathon course and give me that support and that energy. It will be great for the people who couldn't get to the Olympics to see me."
Farah won his only indoor race of the season in 7min 42sec, accelerating in the final laps of the 3,000m to romp home in front of a sell-out crowd – doing the Mobot – at the National Indoor Arena. The victory marked an astonishing 11th consecutive win, bar heats, since defeat in Istanbul at the world indoors last year. Farah will run in the Rock'n' Roll half-marathon in New Orleans next Sunday.
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image: © Fighting Irish 1977