Diane Van Deren is one of the best ultra-runners in the world, and it all started with a seizure. In this short, Diane tells us how her disability gave rise to an extraordinary ability.

For Diane Van Deren, a charming mother of three, daily life is a struggle. But as soon as she steps outdoors, she's capable of amazing feats. She can run for days on end with no sleep, covering hundreds of miles in extreme conditions. Reporter Mark Phillips heads to Colorado to get to know Diane, and to try to figure out what makes her so unstoppable.

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