Marathon Man’s Heart Damaged by Running?

A Minnesota man ran marathons for 21 years and is now a volunteer for a medical study. It's a decision that likely saved his life.

To say running is a passion for Roger Carlson, 65, would be an understatement.

Carlson started running on January 1st, 1988, and didn't stop for 7,813 days.

Carlson has competed in 42 marathons and recently saw an ad looking for marathon runners to participate in a study at the Minneapolis Heart Institute Foundation.

But after getting a heart scan, it was clear that would not be the case. Doctor rob Schwartz says Carlson’s heart was full of plaque. So much so, it was clogging a major artery.

On the advice of doctors, his streak of running every day for more than 21 years ended.

To save his life, doctors inserted a stint, allowing blood to once again flow to the heart.