RALEIGH, N.C. — Most people cannot compete in an iron man triathlon without being in great shape. A 32-year-old man has the lungs for it even if they did once belong to someone else.

Scott Johnson does not take breathing for granted. He grew up with cystic fibrosis. The genetic disorder fills the lungs with mucus and makes breathing difficult. Four years ago, bacterial pneumonia ravaged his lungs beyond repair.

"I went into the hospital to basically die or get a transplant," he said.

Johnson got the transplant at UNC Hospitals in September 2001. Before the operation, he wrote a list of all the things he wanted to do if he survived.

"I vowed that if I did pull through it, I'd start checking those things off one at a time," he said.

Johnson has checked off 13 triathlons since then. An iron man triathlon in New Zealand in March is still on the list. The challenge began as a selfish one, but not anymore.

"Over the years that I've been doing this, it's sort of evolved into, 'Yeah, I run these races for people that are sitting in the hospitals,'" Johnson said.

Dr. Frank Detterbeck, Johnson's surgeon, tells his patients who are awaiting organ transplants that they can look forward to normal active lives, even if it does not involve triathlons.

"A lot of thanks goes to the donor families, that are willing to share the organs at a time of tragic loss. That's what makes all this possible," Detterback said.

That fact is never lost on Johnson, even in the heat of competition.

"Whoever's lungs I have inside of me, that person lives on, and I'd like the family to know that," he said.

Without transplants, people with cystic fibrosis cannot expect to live much longer than 30 years of age. Those on transplant waiting lists can expect to wait an average of five to six years for a suitable donor.