Two weeks after running her first marathon, Kersti Colombant, an otherwise rational woman was ready yesterday for her second. She is 37 and the mother of three, with as many intensely personal questions waiting to be answered as any of the 5,987 other contestants in the Marine Corps competition.

"My husband started running first," she had said, "and I noticed a difference, not just physical but in in the way he was more relaxed with me and the kids. So I tried it - and the first time out I couldn't get around the block.

"I was horrified. I didn't smoke - and in fact considered myself rather athletic. It took me a year to run two miles without stopping and two years to run six miles. But I also started to feel better. The headaches I used to get were gone; I lost 30 pounds without trying."

On the jeep that cleared the way for 26.2 miles was the permanently etched sign: "Convoy Follows." That was apt yesterday for the Kaleidoscopic waves of runners; from her position when the howitzer sounded the beginning of the race it took nearly three minutes for Colombant to reach the starting line.

For the occasion, a traditional athletic role was being reversed. Colombant's husband, Denis, who ran the Marine Corps event in 2 hours 46 minutes last year, was minding the children and waiting with water, juice and slices of orange at various points along the way.

"I was always athletic in high school, but only the exceptional women did anything beyond that. I'd always regretted that the athletic part of my life had seemed finished. But I could see a change when I started running.

"I felt athletic - and it was a feeling I liked my body was in control. I like the crowd aspect, running with other people. Two parents cannot train for the same marathon. Things do get edgy around the house - and my husband has been very supportive."

At about the seven-mile mark, the leaders came by almost 25 minutes before Colombant. This is what is known as the end of the warmup phase, when each runner begins to realize what pace can be carried until the end.

Colombant was on 9-minutes-per mile, comfortable but also irritated. There were no cups at the first water station. So far, so good.

"Before the New York Marathon, I was very excited - and this probably was one of the reasons I began to cramp after 13 miles. I had not been as excited about something like that in a long time.

"I just loved New York. The crowds were fantastic, all the neighborhoods, all the views. I decided to run like a tourist, to enjoy it and stop worrying about physical problems. Just enjoy.

"But at 13 miles I got cramps in my calf. I was walking and looking ever so horrible, but instead of yelling, 'Go, Go!' those wonderful New Yorkers shouted: 'Darling, you look just beautiful!'

"Because I walked and run the last half of the race, I don't think I hit the 'wall.' About 100 yards from the finish somebody handed me a cold beer. And when I crossed the finish line (in 4:34.30) I felt like a real athlete. I was so excited I cried."

If the weather was too hot yesterday, Colombant decided to drop out about the halfway point and use it as a training run. The temperature sneaked into the 70s and others wilted, but she seemed in control through 10 miles.

In truth, the celebrity of the family was 8-year-old Natacha, who had carefully lettered three cardboard signs more than her mother appreciated. She held the first sign, "Go, Mom, Go." at seven miles - and most everyone who noticed it could still smile.

"Natacha's second sign, "Go For No. 2," was personal. But her third. "Finish It," was a burst of inspiration for dozens of runners at the 17-mile mark. She held it prominently for more than a half-hour; a few appreciative runners would mutter thanks, some would give her an affectionate pat; others would set their jaws a bit more firmly.

"I think it's important for my daughter to see me in competition. If the mother who works (as a teacher), sews and cleans house also can do something like this, it shows her different possibilities are available to women.

"Not that she must run, but that these possibilities exist. But sports was not encouraged for girls when I was younger. I've overcome a disappointment in life because of when I was born."

At 17 miles, Colombant began to cramp. At the four-hour mark, Denis left the final family perch, 600 yards from the finish line, to jog out and escort his wife home. She wanted to be left alone, to walk-stumble up the last hill and over the finish in intense pain and also intense joy.

Along the way she had stepped on a dead rat and met a former playmate she has not seen in 32 years. At times, there had been water but no cups and cups but no water.

"I walked preventively" to keep from cramping, she said moments after rejoining the family and learning she had cut eight minutes off her New York time.

"After 20 miles, I'd stretch and walk and run. But I never felt I couldn't run."

Like New York, this had been "a fantastic moment in my existence."

Donna Carty, 29, of Groton, Mass., was the first woman across the line, in 44:28. Susan Hughes, 27, of Wellesley, Mass., was second in 45:25, while Eileen O'Rourke, 14, of Arlington, Mass., was third in 48:45.