“I don’t have an athletic bone in my body,” protests Diane Bell. “I’ve got two skinny, long legs. I don’t know what else.”

To which the only proper answer must be, “Yeah, right.” Bell, 63, was speaking four days after running the Maine Coast Marathon (where she finished in 4 hours, 59 minutes and 36 seconds) and just a few hours before heading to Portland to do Munjoy Hill workouts with a group that trains out of Fleet Feet Maine Running Company on Thursday evenings.

Bell’s time at the Kennebunk-to-Biddeford 26.2-miler on Sunday was almost a 10-minute improvement on her debut marathon, which was Maine Coast 2013, and while she was “pretty glad” to have broken 5 hours, she had hoped to be around 4:45.

“Believe it or not, the heat didn’t bother me, but I did have a little respiratory thing, like bronchitis, so I felt lucky to be able to run in the first place. It’s a beautiful course, so I tried to take advantage and enjoy that, to get my mind off what I was doing.

“And why am I doing it?” she breaks off. “I don’t know!”

Anybody who has ever raced a marathon understands exactly Bell’s state of mind during the grueling later miles, when her second-half split was about 20 minutes slower than the first. Her overall motivation to run, period, comes from various directions.

Growing up in Westbrook, Bell didn’t play sports. Attending a two-year college in Vermont, she was smoking two packs of cigarettes a day. As a wife and mom working as a medical transcriptionist, “I was a couch potato.”

A life change began in the early 2000s. Her husband, Reed, was diagnosed with colon cancer years earlier. Diane got moving first by walking, then training for and completing a 40-mile benefit for the Colon Cancer Alliance in 2003. Ten years ago this month, Reed died.

Entering her late 50s, Bell moved from walking to running, and then racing. Her first event was the Kerrymen’s Pub 5K in Saco in 2008; she ran 29:14 and raised money for the Maine Cancer Foundation. She’s run the Kerrymen almost every year since (missing only 2011 because of injury) and continued her fundraising, both at that event and at the Tri For A Cure, in which her daughter, Jaime Bell Fairfield of Cumberland, has competed.

Bell is modest about her fundraising (“a few dollars”) and her performances, though her time at Kerrymen’s Pub was quicker this year than six years ago (26:35), and often finishes in the top three for her age-group.

Asked about her statistics, she replies that “I don’t have a clue most of the time.” But after digging around a bit she’s able to cite PRs of 1:55 in the Maine Half Marathon, 51:55 for a 10K (Portland Trails) and 24:11 for a 5K.

How often does she race? “Oh, lordy, I don’t even know … 21 races in 2012. Which is nothing compared to some of my friends.”

The social element is a big part of Bell’s devotion to running — she refers to the Thursday night sessions as “group therapy, more or less” — and she is quick to list the accomplishments of others, including good friends Margaritt McNulty, 62, of Standish, 4:47:04 at Maine Coast (“Her first marathon and she beat me, the little twit”) and Jim and Laura Tyrrell of Cape Elizabeth, both 66, who ran 4:44:37 and 5:00:01 on Sunday.

Bell disdains the treadmill, even in a winter as harsh as the one just past. She walks or bikes the mile to her job as a cashier at Hannaford in Gorham, and sometimes gets creative on solo runs. Needing to get in a 12-miler a couple months ago, she ran six miles from home to the Kohl’s in Westbrook, used the ladies’ room, picked out some workout clothes and stashed them at the service desk, then ran home.

Upcoming races, assuming Bell isn’t hampered by the various injuries that have popped up from time to time, include a Will Run For Beer 5K in New Hampshire next month, probably the Maine Half Marathon in October, and possibly even another marathon at some point.

“I just got done saying I’d never do one again, but I said that last year,” when she finished Maine Coast “feeling as if I was being stabbed in the knee over and over. But a marathon is like having a baby. You don’t remember the pain you went through.”

Speaking of babies, there’s an added joy in Bell’s life beyond running: Jaime’s son, Grayson Reed Fairfield, who turned 10 months old Wednesday.

Running has taken 40 pounds from Bell’s 5-foot-6 inches. “After that marathon, my weight is probably the lowest for a long, long time.”

Down to what? “I think I’ll bypass that question.”

MAINE COAST hit its cap of 750 registrants in February, and there were 621 finishers. The winner was Jefferson Welch, 27, of Haverhill, Massachusetts, in 2:42:36, just over seven minutes ahead of Erik Russo of Johnston, Rhode Island. Women’s winner was Mary Klene, 30, of Manchester, New Hampshire, in 3:12.59.

En route to a top-25 finish if all went well — 1:34.54 at the half — was 24-year-old Daniel Hoff of Cambridge, Massachusetts, running his first marathon. But at about the 14-mile mark, on U.S. Route 9 in Kennebunkport, Hoff was hit from behind by a car driven by a local woman who was not charged with a crime in the incident.

“It appears that the operator of the vehicle was trying to pass at a slow speed around the runner and pulled in too quickly and (the right front corner) caught the runner … who did strike the windshield,” said Kennebunkport Police Chief Craig Sanford.

Hoff had a head cut and was attended to almost instantly because an aid station was very close by. He had no broken bones, was released from the hospital Sunday night, and later in the week was doing well, race director Charles Melton said after talking to Hoff’s mother.

If Hoff wants to return, he’ll be welcomed.

“We’ll comp him any time he wants,” Melton said.

John Rolfe writes about road racing for the Maine Sunday Telegram. He can be contacted at 791-6429 or at jrolfe@pressherald.com