In the run-up to Sport Relief, Greg James meets up with his heroes of the charity event, including David Walliams, Eddie Izzard, Davina McCall, John Bishop and Zoe Ball.

A defining feature of Sport Relief is the willingness of celebrities to undertake gruelling challenges in order to inspire the public to donate and get involved with the cause. Greg looks back with those who have put themselves to the test and beyond for the charity, finding out what motivated them.

Eddie Izzard drove himself to breaking point in his quest to run 27 marathons in 27 days as a tribute to Nelson Mandela, while David Walliams has swum both the channel and a 140-mile stretch of the River Thames. Few will forget the iconic scenes of John Bishop climbing the steps at Trafalgar Square after a long journey by bike, boat and foot from Paris, or of a weepy Davina McCall finishing her seven-day, 500-mile triathlon from Edinburgh to London, while Zoe Ball cycled from her birthplace in Blackpool to her home in Brighton to raise awareness for men’s mental health. All were spurred on to raise money for Sport Relief and those in need. Show less