Running fanatic James O’Shea is set for an energy-sapping challenge when he competes in the world’s greatest ultra-marathon, the Comrades, in South Africa this weekend.The gruelling event will see the Bermudian thrill seeker clock up 56-miles between the capital of the KwaZulu-Natal province, Pietermaritzburg, and the coastal city of Durban.A Cambridge University graduate, O’Shea is no stranger to tough tests of endurance having completed the New York, Boston, London and Chicago marathons in recent years.The Comrades Marathon will be a much sterner test, though, for the London-based 24-year-old, who will again be running in his ‘lucky’ Bermuda jersey.“He’s been doing long runs around London to try and get ready for the race,” said his mother Linda O’Shea. “He’s been running 35-40 miles to prepare for this thing.”O’Shea, an ex-Warwick Academy pupil, who works as a trainee solicitor with Covington & Burling in London, will be raising money for the Make A Difference Foundation (MAD) in South Africa.MAD was set up by ex-South African rugby skipper Francois Pienaar, who led his country to victory in the World Rugby Classic in Bermuda a few years ago.The charity identifies South Africa’s talented but underprivileged children and provides them with access to the best schools and universities.O’Shea’s mother added: “It’s a charity my husband (Paul) has been involved in over the years as his boss knows Francois Pienaar,” she said.“Running in South Africa (James) felt it was the appropriate charity to raise money for.”The Comrades was the idea of First World War veteran Vic Clapham, who wanted a living memorial to those South African soldiers killed in the war.It first took place in 1921 and has been run every year since, except from 1941 to 1945 when it was stopped during the Second World War.Forty-eight runners entered the first race, but when the starting shot was fired, only 34 had the heart to tackle the daunting task.Each year the race alternates annually between the ‘up run’ from Durban, which is considered more difficult, and the ‘down run’ from Pietermaritzburg.More than 23,500 runners took part in the race’s 85th anniversary in 2010, which took place a little earlier than usual so not to clash with the FIFA World Cup.