Holocaust survivor Nat Shaffir, 81, didn’t start running until he was 65, but when he did, he discovered something magical: The sport gives him the endurance to share his life story.

Shaffir gives tours of the Holocaust Museum in Washington D.C., and tells visitors about his life, which started in Romania, but suddenly took a major turn.

“One of our neighbors was a priest,” he told CBS News. “He showed up with a police officer and two armed guards, and he’s pointing at us and he’s saying… ‘these are Jews.’ So we were actually turned in to the authorities because we were Jews, by a priest.”

The family farm was confiscated, and Shaffir and his sisters were no longer permitted to attend public school, according to the U.S. Memorial Holocaust Museum.

His family lived in poverty in a Jewish Ghetto, and 32 of his relatives died in concentration camps. Eventually, Shaffir’s parents were able to flee Romania for Palestine, where Shaffir served in the Israli army. Eleven years later, he moved to the U.S., started his own business, married and had five children.

He started running later in life after meeting a college student who had run a marathon. He thought, if she could do it, he could, too.

He completed one marathon and that was enough to ignite the fire within. By the age of 81, he was contemplating running his 12th 26.2-mile race.

When he’s not racing, his training consists of six-mile runs, six days per week. He says he doesn’t listen to music or daydream. Rather, he reflects on the difficult years of his life abroad so he can tell his grandchildren and museum guests stories in order for history to live on through the generations.

“I’m their voice,” he told Today. “Later on, when we [Holocaust survivors] are gone, these young people will be our voices, and the Holocaust Museum will be our voices,” he says. “We are actually fighting a war, which means time.”

And it’s time so much more important than anything that can be displayed on a clock at a marathon finish line.