Mo Farah has revealed how the biggest gamble of his career turned him from a weakling who runs 'like a girl' into a double Olympic champion.

Farah claimed gold in the 5,000 and 10,000 metres at the European Championships in Barcelona in 2010, but knew that he still needed to improve on the world scene after finishing sixth and seventh in the previous two World Championships.

The 29-year-old, who had also failed to qualify for the Olympic 5,000m final in Beijing in 2008, therefore split from long-term coach Alan Storey and moved his wife Tania and daughter Rihanna - aged five at the time - from their London home just 17 months out from London 2012 to work with Alberto Salazar in Portland, Oregon.

Catching on: Mo Farah does the Mobot alongside Pele and David Cameron at Downing Street

Top team: David Cameron and Mo Farah hold a baton aloft, with Pele (front centre) and Haile Gebrselassie (right)

And the move has paid enormous dividends with Farah last night becoming only the seventh man to win the long-distance Olympic double, with London 2012 chairman Seb Coe - himself a former Olympic champion - hailing Farah as 'probably the greatest runner this country has produced'.

'There were a lot of questions asked at the time I moved to America because I was double European champion and people were like, "Mo, why are you changing when things are going so well?"' Farah said.

'But in your mind you know something had to change because I was coming sixth, seventh, and if I didn't make that change I don't think I would have been here today and competing with those guys.

'It felt like it was a gamble, moving my daughter out of school, taking my wife and not knowing too much about the place - it was good for training, that's all I knew. Half the year I am away as well so you have that responsibility as a parent and husband to make sure they are happy. I am glad my wife does like it.

No 10: Farah does his now famous celebration outside Downing Street

'I knew it was the right thing because I was weak. Alberto said I run like a girl, in terms of not using my arms when I'm sprinting, when I'm tired I'm all over the place. It needed to change so if I wanted to be better it was the place to be, but how long can I stick at it and make the sacrifice.'

Salazar, a Cuban-born former athlete best known for winning the New York marathon for three years in succession from 1980, came in for criticism when Farah failed to win a medal at the World Indoors in Istanbul in March, with suggestions that Farah and 10,000m silver medallist Galen Rupp were covering too many miles in training.

But the 54-year-old's methods ultimately worked to perfection, with Farah able to run the last lap of each victory in 53 seconds to hold off the chasing pack.

'Alberto is a genius,' Farah added. 'He got a little bit of criticism in Istanbul when things didn't happen my way, but to move on from there and get it right for me in London is incredible because this opportunity ain't going to come round again.

Magic MOment: Farah celebrates his 5,000m win

'It was only the last lap really and that's been the difference, 1 or 2%. I've always had it but I just haven't been able to finish races, now I am finishing races strong. They were queuing up to pass me and I could feel that but I wasn't going to let anyone past me. It's an incredible feeling.'

Even Usain Bolt paid tribute to Farah's achievement by performing the Briton's 'Mobot' celebration as he crossed the line after breaking the world record in the 4x100m relay.

And Farah revealed that his daughter Rihanna was far more impressed by the Jamaican superstar than her dad's two gold medals.

'Me and Usain get on well, we have a good relationship and my daughter loves him,' Farah added. 'Yesterday that made her day; he gave her a hug and she took a picture of him, she was like "Bolt, Bolt, Bolt!"'

Farah's gold medals will take pride of place at his home in Oregon - where he even has a treadmill in his bedroom - the Arsenal fan having left a space next to his World and European medals and a signed Gunners shirt.

Track kings: Farah with the greatest sprinter ever, Usain Bolt

And he wants to add more medals to the collection, even though he is also tempted to step up to the marathon.

'I'm not sure about next year but I do want to run the London Marathon. I am quite excited about it, the crowd, it would be amazing,' added Farah, who will run a half-marathon in the Great North Run on September 16.

'It's an option but I have not talked to Alberto or Ricky (Simms, his agent). I believe Alberto will probably say it's too early for the road, keep up the track. Things are going well and as an athlete you want to be able to collect as many medals as possible throughout your career. I want to keep going now.

'To be a legend like Bolt you have to go from track, world records, the marathon; there is lots of stuff to be done and I don't consider myself to be a legend or anything like that.'