He used to be able to run a mile in less than five minutes. But a terminal lung disease has robbed Evans Wilson not only of one of his favorite pastimes, but his ability to breathe.

Wilson was diagnosed at age 57 with pulmonary fibrosis and pulmonary hypertension. The former causes the scarring of lung tissue, and can be the result of exposure to particles, genetics, or autoimmune diseases. The survival rate for someone with both conditions is only about three years.

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Now 63, Wilson has defied the odds.

Hoping to raise awareness about the disease and funds that will go toward research and a cure, Wilson signed up for the Seattle Marathon this past weekend. His doctors discouraged him — but he was determined to both do the race and finish.

Given a 1 hour, 15-minute head start on the rest of the field, Wilson and his wife walked all 26.2 miles of the race route, with his oxygen tank in tow. He finished in just over 11 hours — three hours sooner than he thought he might.

“I’m in pretty good shape if I didn’t have heart and lung disease,” Wilson told KOMO, the ABC news affiliate in Seattle. The first 10 miles felt good, he said, and the other runners were incredibly supportive.

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“A lot of them, they’d give me a clap as they’d run by,” said Wilson, explaining others had seen him on TV as he trained. They said, “‘I saw you on KOMO, way to go!’ It makes you feel good.”

Nearly 40,000 Americans die of the disease annually, according to the American Association for Respiratory Care.

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The only known treatment is a lung transplant.