The network morning show CBS This Morning has a recurring series called “Pushing the Limits.” It was only a matter of time before they took a closer look at the boundary-push sport of skyrunning.

A CBS crew was in Montana recently for The Rut Mountain Runs, and interviewed several prominent ultrarunners like Max King, Emelie Forsberg, Luke Nelson and more, to try to get inside the mind of what pushes a runner to run 50K and beyond across punishing terrain and extreme elevations.

RELATED: Photos: The Rut Mountain Runs, 2015

The feature is below: