Eric Gelber is a man on a mission. He’s on a one-man quest to wipe out multiple myeloma, an incurable blood cancer.

He started running in 2007 to raise money for the Multiple Myeloma Foundation after a close friend was diagnosed with the disease.

This year, he decided to push himself further than he ever thought possible. He ran for 44 hours straight (although he admits he took three 15-minute naps along the way) and 155 miles through New York’s Catskill Mountains.

That’s like running six marathons — in one try.

Eric says he runs because the research funded by runs like his are the only reason his friend is still alive.

He hopes more people will do more to help eradicate disease that is 100 percent fatal.

Eric reveals how long runs like this can sometimes make him feel wacky and even hallucinate. Find out what he thought he saw along the way.

Plus, find out how how 155 miles can actually be an exciting distance to run.