A New Zealand ultra-marathon runner is moving closer to a world record, by running loops in a backyard in the United States.
Sam Harvey from Christchurch is competing in Big Dog's Backyard Ultra in Tennessee, a gruelling race that has brought together the world's top 75 multi-day runners from 38 different countries.
All Harvey has to do to be declared the winner is outlast his fellow competitors.
Sports reporter Felicity Reid joins Lisa Owen in studio.
