The 47,000-mile marathon

An inexperienced runner is attempting seven "ultramarathons" in seven days on seven continents to raise money for vulnerable young people.

Oliver Dudley, 32, is attempting a world first with the challenge, which will see him complete seven 31-mile runs.

He hopes to raise thousands of pounds for charity Kids Company to help seven children in its Young Entrepreneurs Group.

His first ultramarathon will be on Saturday in Antarctica, followed by Punta Arenas, Chile, on Sunday, Los Angeles on Monday and Brisbane on Tuesday. On Wednesday, his daughter Amelia's second birthday, he will run in Hong Kong and on Thursday in Johannesburg. On Friday, heading into Saturday, he will complete his challenge in Hyde Park.

The route, 217 miles running and 47,000 miles flying, can be followed online, with his sponsor Nokia supplying him with a tracking device. All carbon emissions generated by the expedition will be offset.

Mr Dudley, a property developer from Battersea, said: "It will be gruelling. My body clock will be confused by jetlag, sleep will be limited to power naps between flights and my muscles will not have time to recover meaning that damage and severe cramps are inevitable." He has been training for three months, including intensive running, cycling, yoga, weight training, cardiovascular workouts and stretches.

Mr Dudley was a keen rugby player until he broke his neck in 2000. In 2007, having never rowed before, he joined the crew of La Mondiale, which set a world record for the fastest oar-powered Atlantic crossing.

He was introduced to the seven children by Kids Company last year, and said he was so impressed with their ambition he decided to raise the cash they needed to study or set up small businesses.

"I see this as a way to invest in their future," he said. "I'm an entrepreneur and found it hard starting out in the world. By running and mentoring these young people, I have the chance to make a difference to their lives."