John McDonnell: 'Jeremy Corbyn is the fittest person I know'
The comments will come as a major blow to the eight Labour MPs who ran in last year's London Marathon.
Jeremy Corbyn's right-hand man has said the 70-year old Labour leader is the "fittest person he knows" after questions about his stamina surfaced ahead of an impending general election.
Mr Corbyn, who has admitted to suffering with eye weakness, reacted with fury earlier this year when it was reported in the Sunday Times that civil servants were concerned about his frailty.
But asked about Mr Corbyn's "energy" in an interview for GQ magazine with former Labour spinner Alastair Campbell, Mr McDonnell claimed: "Jeremy is the fittest person I know."
Mr Campbell fired back: "He's not the fittest person you know John."
But the Shadow Chancellor was adamant, adding: "You obviously don't know who I mix with! You mistake Jeremy's style, you really do, these zen-like qualities the media write up. He's a very quiet, caring, compassionate person.
"He's a consensus builder and he'll work through the issues and then that’s it, decision made."
Earlier this year Mr Corbyn was snapped taking part in a vigorous gym session with a top personal trainer. The pensioner was pictured cycling, running and doing sit-ups in Finsbury Park alongside his wife.
And according to personal trainer Samuel Ebi-Taubmann, the Islington North MP is in tip-top shape.
"He does this strength session with me, then does two laps of the park at a fast pace," he told the Sun in July.
"Not many 70-year-olds could manage that.
"But Jeremy's got a tougher job than most 70-year-olds, so he needs more strength and stamina. I'll get him in great shape."
It comes after Boris Johnson was reportedly put on a strict diet during the Conservative leadership campaign by partner Carrie Symonds.
The PM-in-waiting was forced to slim down after he admitted in 2018 to weighing 16-and-a-half stone following a diet of "chorizo and cheese" binges washed down with "bathfuls" of booze.