Jamie McDonald, from Gloucester, has already spent the past 11 months taking part in 197 marathons in a coast-to-coast trip across America spanning 5,500 miles.
Pride of Britain winner, 32, will attempt to smash the Guinness World Record for charity
Jamie McDonald, from Gloucester, has already spent the past 11 months taking part in 197 marathons in a coast-to-coast trip across America spanning 5,500 miles.