After 81 years, Clarence Hartley is finally running the Boston Marathon. What took him so long? First there were two wars — Korea and Vietnam — where he served in the United States Air Force. Then he spent years stationed in Taiwan, Japan, Thailand, Germany, and England. More recently, he battled lymphoma and prostate cancer. But on April 18, Hartley will set off on a well-deserved journey from Hopkinton to Copley Square.

At a time in life when even the most active runners show signs of slowing, Hartley is still running strong. He'll be the oldest entrant in this year's Boston, having qualified last May with a 4:39 marathon (he needed 5:00); he's since run a 4:26. He's just 13 minutes shy of the American record for 80-to 84-year-olds, but Hartley is more keen on "beating several thousand younger runners," he says. "The last time I felt so good was on my final combat mission in the Air Force in 1969. We did a barrel roll flying back to base, and my crew threw me in a pool."

Unlike many runners, Hartley didn't set out to qualify for Boston in his youth.

"When most runners are in their prime, I was in combat," says the retired lieutenant colonel, who served in the Air Force for 24 years and received the Distinguished Flying Cross and five air medals. It wasn't until years after he retired and moved with his wife, Riki, to the town of Young Harris, Georgia, that Hartley started running. One morning there in 1998, when he was 68, Hartley saw a race take place near his home. "It looked fun," he says, "so I decided to try it."

Over the next seven years, Hartley ran close to 150 road races, setting state age group masters records in every distance up to the half-marathon . ("Of course," says Hartley, "my age group gets smaller every year.") In 2005, Hartley needed a bigger challenge. He set his sights on the marathon, running his first in 4:09 and qualifying for Boston. But he was soon diagnosed with non-Hodgkin's lymphoma and had to put the race on hold while he underwent chemo. Two years later, he found out he had prostate cancer. "I remember lying on an exam table thinking about Lance Armstrong and what he accomplished," says Hartley. "I thought if I survived, I'd come back like he did and run Boston." Now he's cancer-free. Doctors and friends alike are impressed he's run this far from both diseases.

Marathon and your heart
"I can't count the times I've heard runners say they want to compete like Clarence when they're his age," says Kristian Blaich, 44, a friend and fellow Atlanta Track Club member. "If someone in his 80s can race at Clarence's level, the rest of us can exercise a few times a week."

Mike Hewitt / Getty Images The Week in Sports Pictures

Hartley credits his late-age running success to good genes, but also to the competitive nature that led him to fly more than 100 combat missions in his youth. Today, he runs every other day, logging about 25 to 30 miles a week as he gears up for Boston.

On a cold Saturday afternoon this past January, the retiree let a 29-year-old reporter join him for a training run. On the last mile, Hartley put down a challenge: "Sprint you to the end," he said, as he raced ahead, with the younger of the two barely pulling ahead. "It's fun being old when you're healthy and in shape," Hartley later said. "I have to look for porta-potties more often, though. Hopefully there'll be plenty of those at Boston."

Running the Numbers

• 449 Number of entrants at Boston who will be 65 or older
• 2 Number of entrants at Boston who will be 80 or older
• 83 Age of the oldest person to run Boston in the last five years

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