By Justin Udo

SHARON HILL, Pa. (CBS) – A 50-kilometer, 24-hour ultra marathon is off and running. That’s the goal for more than 30 runners at Academy Park High School in Delaware County.

The crisp morning air was biting at the runners who traveled from all over the country when they started their race – all about mental and physical determination – at 7 a.m. on Saturday.

Dan Schultz is a teacher at the school. This is his 5th ultra marathon, but he says being able to do it at the school he teaches at makes it pretty special:

“I’ve seen about seven to ten of my students already. I feel good and I know already that they think it’s impressive. I think that shows them that teachers out here doing it that they can do it. They are strong young kids they can do anything too.”

Dan has a goal of running 78 miles, but some of the other runners are doing more than 100 plus miles.

To put that in perspective, that’s more than three Philadelphia marathons and three Broad Street runs all in one day.

And some of the oldest runners in the race are in their 60’s.

The marathon ends Sunday morning at 7 a.m.

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