He also described himself as an unelectable "prat who gets stuck on a zip wire".
More seriously, he disclosed he was considering how the army of volunteers acting as guides and helping with the promotion of the Olympics could be recruited as long-term volunteers to help with sport in schools.
He added that one of the most moving aspects of the Olympics had been the number of people who volunteered to help.
He said: "They are doing stuff in their own free time. Wouldn't it be a wonderful thing if we could mobilise them, and people who want to join them, through Team London to help with sport in schools?
"It is often not the shortage of facilities, the problem is a shortage of people who have got the CRB checks and all that stuff who are willing to come and help out."
Appearing on ITV's Daybreak programme, he jokingly dismissed talk of him becoming the next prime minister.
The mayor was shown footage of him stuck last week on a 150ft high, 1,000ft long zip wire at the London Live event in Victoria Park, east London, when he was left hanging over a crowd of people for several minutes as the wire lost momentum.
"There you have got it, how on Earth could you elect that guy? How could anybody elect a prat who gets stuck in a zip wire?" Johnson said.
He added that the experience had been "slightly scarier" than it appeared, joking that his actions had been heroic.
Asked if he wanted to be prime minister, he said: "No, of course not, because I have got four years of mayor of London ahead … perhaps this is the moment to knock this once and for all on the head?
"I am mayor of London and my cup runs over, and plus … we have got the Paralympics and they are going to be fantastic too."
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