Everyone's been vowing to get fit this year; whether it's going for that extra run, hitting the gym more often or walking to the store instead of driving. But we're willing to bet no-one's taking to an extreme like Eddie Izzard, who has claimed to embark on 27 marathons in 27 days.

Eddie IzzardEddie Izzard gets his running shoes back on

One marathon in one day is enough for us; we'd even be impressed with two in a year. But 27 marathons in 27 days?! That's not all either, because Izzard will be taking to the sweltering climate of South Africa for this challenge, a far cry from UK temperatures and probably not the most comfortable to exercise non-stop in.

As part of this year's Sport Relief, the comedian is looking at running over 700 miles in 30 degree temperatures over a period of 27 consecutive days in a challenge called Eddie Izzard: Marathon Man. It's in honour of the late anti-apartheid revolutionary Nelson Mandela, who died in 2013, and reflects the 27 years he spent in prison for allegedly conspiring against the government. 

Plus, Izzard will be travelling along a route specifically surrounding areas significant to Mandela, from his birthplace in Mvezo, through his places of early education, the University of Fort Hare, Cape Town and Robben Island where he was thrown behind bars.

More: Read our review of 'Mandela: Long Walk To Freedom'

The marathon 'marathon' begins on February 23rd 2016, with proceeds towards the event going to the Comic Relief offshoot. It's a brave thing for Izzard to take up, giving that he struggled to complete his last challenge in 2012, but he has previously managed 43 marathons in 51 days - though that, of course, took place in the UK.

'Eddie is undoubtedly one of our Sport Relief legends, and we are absolutely thrilled that he is going to push himself to the physical limit once again', said Comic Relief CEO Kevin Cahill in a statement.