Kiwi endurance runner Sam Harvey is at it again, just weeks after claiming he was done with ultra back yard running "for now".
Picked to be a favourite at the Big Dog's Backyard Ultra in Tennessee last month, he stunned the crowd when he pulled out after 91 hours, 73 km short of the world record.
The event is gruelling - with competitors running a 6.7km loop every hour, only finishing when there's one person left able to run.
Sam is competing in the Arrowtown Backyard Ultra tomorrow and speaks to Susana Lei'ataua.
