BOSTON - Qualifying for and completing the Boston Marathon carries a singular prestige in the sporting world. Sean Luitjens, a 1987 University High School graduate, has taken on that challenge and doubled it while also raising money for heart research.

Luitjens will join his friend, Bill Nawn, in covering Boston's 26.2-mile route twice on Monday as the event celebrates its 111th running.

They will start at the finish line in Boston and run toward the starting line in Hopkinton, Mass., where they will join the 20,000-plus other official entrants for the 10 a.m. race back to Boston.

Luitjens, who played baseball at U High, first did this "Heart2Heart Run" in 2004. He did it again in 2005, but missed last year because he was moving to Jericho, Vt.

The 37-year-old Luitjens and Nawn, 43, of Manchester, N.H., use this challenge to raise money and awareness toward better identification and treatment of heart disease.

Ironically, both men have heart conditions.

Luitjens - whose father, Roy, and stepmother, Rosemary, reside in Bloomington - was diagnosed with Premature Ventricular Contractions (PVC) two years ago.

"It was a little concerning," he said. "I had to cut back on alcohol a little and I had to cut back on caffeine."

All of the money raised this year will be donated to the Lown Cardiovascular Research Foundation in Brookline, Mass., where Nawn was treated for heart arrhythmia.

Nawn has run this "Boston Double" five times and raised $85,000 for charity. Those wishing to donate can visit www.heart2heartrun.org.

Luitjens and Nawn typically run the mostly uphill first 26.2 miles from Boston in 3 hours, 30 minutes and return in 3:50 to 4:14.

"Heartbreak Hill hits nine miles from the end," said Luitjens, whose marathon best is 2:49. "Miles 42 to 46 are pretty tough."

Luitjens said there are no spectators lining the streets when he and Nawn start.

"About halfway out, you start to see the course coming together as they block off roads and put up barricades," he said. "It's a cool way to see how much work goes into the race."

As Luitjens and Nawn get closer to Hopkinton they encounter more and more spectators, many of whom think they are original in shouting: "You're running the wrong way."

Luitjens and Nawn met in 2000 when they almost literally ran into each other on a trail while training. Their friendship has featured each challenging the other to complete an endurance race of some sort. Their series of challenges led to the "Boston Double."

Luitjens, a 1992 Florida State University graduate, started swimming and bicycling to rehab a basketball injury. In 1991, he did his first full Ironman triathlon, swimming 2.4 miles, biking 112 and running 26.2.

Luitjens has completed 175 triathlons and many ultra marathons, the longest of which was 100 miles. He considers the 100-miler his biggest athletic achievement.

"I used to say the Ironman, but my first 100-mile trail race took 24 hours," he said. "That was significantly different. In the Ironman, if you are a good athlete, you're not out for more than 11 hours. Being out 24 hours was interesting."

Luitjens supplements his 60 to 100 miles of training per week with three days of swimming and four of biking except in the winter when he replaces biking with cross country skiing.

Luitjens, a vice president for Mercer Human Resource Consulting, credits his wife, Jennifer, for supporting his hobby. They have three children ages 9, 7 and 5.

"She's the one who keeps my priorities straight," he said.

A priority next September will be to return to Normal for Luitjens' 20-year class reunion.

Based on his training mileage alone, he should win the prize for having come the farthest.