Jamaican track star Usain Bolt could win four track golds at the Olympics after admitting he may run the 4x400 metres relay.

The 25-year-old comes into the London Games as the defending champion in the 100 and 200m as well as the 4x100m relay.

But he hasn't ruled out the 4x400m relay as well.

"I always see how I come out of the 200m before I decide, like if I'm tired etc," said Bolt, who will carry the Jamaican flag at the opening ceremony on Friday.

"If I feel up to it, why not? For my country I would always do what is necessary.

"It all depends what is needed from me because at the end of the day it is about the team.

"However, there are limits and the individual 400m no chance."

Bolt, one of global sport's most marketable personalities, said that his mind was not on the times he would run but his ultimate goal of being termed a legend -- that would only come if he defended his titles.

However, he admitted that should he miss out on his goals at the Games then it would not be a catastrophe.

"I don't think it will be the end of the world if I lose," said Bolt.

"I would definitely be disappointed if I was second. Mentally though I am always strong. I have a great team around me who keep me on track.

"I don't think I should be talking about losing anyway as there are friends of mine who will not appreciate that."

Bolt, who also secured triple gold at the 2009 world championships in Berlin, admitted losing in both the 100 and the 200m at the Jamaican Olympic trials to training partner and 100m world champion Yohan Blake hadn't been the best preparation.

"I can't determine what fitness I was at," he said. "I wanted to be at my best level but I wasn't. I can't complain. It's always a wake up call when you are beaten. However, I'm alright I've got used to it."

Bolt's greatest barrier to winning in London is training partner Blake but he was at pains to say that they remained friends and still followed the same training routine.

"Me and Asafa (Powell) are still good friends after years of competing closely against each other," he said.

"So my relationship with 'The Beast' (Blake) won't change at all. People were saying I was training early in the morning and Blake in the evening, but that's not true.

"We do everything or nearly everything (together). Training hasn't changed, only the atmosphere at competition."

Bolt, who said he had put behind him the disappointment of being disqualified from the world 100m final last year after a false start, insisted there was no way this would be his last hurrah.

"I will definitely carry on if I achieve my goals here. I will just set myself new ones. It will definitely be less stressful for me, more relaxed."

Bolt, who retained his 200m world title last year after getting over the disappointment of the 100m, said regardless of his past exploits at senior level the memory he placed above all others came 10 years ago.

"The world juniors in 2002 is the greatest memory of my life," he said.

"Winning in front of my home crowd was greater than Beijing (2008 Olympics)."

He admitted that the huge leap from unknown to one of the best known faces in the world had come at a price.

"I used to be able to walk through an airport or down the street without being recognised, now its impossible," he said.

"I guess I can put up with that for three months a year in Europe. In Jamaica you are just treated like a normal person."

Bolt, though, insisted he would remain the same carefree amiable guy he has always been.

"The 'Mr Cool' name? I'm always cool always relaxed, that's just me. I will never change."