Main content
How does it feel to run 246km?
Dean Karnazes describes the experience of running an ultramarathon
(Photo: Dean Karnazes at the Spartathlon ultramarathon, photo credit to: Babis Giritziotis)
Duration:
This clip is from
More clips from What are the limits of human endurance?
![]()
How to psych up for long distance running
Duration: 01:23
More clips from CrowdScience
![]()
What would happen if we fell straight through the earth?
Duration: 02:34
![]()
Why is aurora green?
Duration: 02:19
![]()
In a random universe, is anything predictable?
Duration: 01:58
![]()
How do birds survive so high up?
Duration: 02:13
