蜜芽传媒

What does it take to be a successful runner of extreme distance, and why do people do it? Playwright David Greig went from a chain-smoking, sedentary lifestyle to an ultra-marathon runner. David talks to fellow ultra-marathon runner Ben Smith, who is attempting to set a world record by running 401 marathons on 401 consecutive days.

First broadcast on One to One, 31 May 2016.