NEW YORK • The simple thought crossed Shalane Flanagan's mind as she raced alone through Central Park: Just keep it together, keep it together.

She would not dare look over her shoulder. Her gaze remained ahead, on the prize that had eluded an American female marathoner like herself since 1977.

The 36-year-old had a vague sense of the history. She felt a more personal stake in this New York City Marathon taking place just days after a terror attack in Lower Manhattan.

It reminded her of the inspiring performance by her friend, Meb Keflezighi, the American male winner of the first Boston Marathon after the bombing in 2013. He was in this race, too, in what he said would be his last marathon.

That is partly why, as the finish line neared, Flanagan, with tears in her eyes, began pointing and shouting on Sunday.

"This is a moment I've dreamed of since I was a little girl," she said, 40 years after the last American, Miki Gorman, won the women's field. "It's indescribable. These are the moments we dream of to realise our potential and see how incredible we can be."

The Massachusetts native won in a time of 2hr 26min 53sec. She finished a full minute ahead of the champion for the last three years, Mary Keitany of Kenya, whose time was 2:27:54. Mamitu Daska, of Ethiopia, competing in the event for the first time, finished third in 2:28:08.

"It has been a tough week for New Yorkers and a tough week for our nation and I thought what better gift than to make our nation and our people smile," said Flanagan, the 2010 New York marathon runner-up who was sixth in last year's Rio Olympic marathon.

"I thought of that when I began to feel the pain."

Kenyan Geoffrey Kamworor won the men's event, his first victory in this distance in his seventh marathon start. Two years after losing the lead late in the race, he held off compatriot Wilson Kipsang to win in 2:10:53.

"I'm so happy. I feel so great to be the champion," he said. "This is my first marathon victory."

Kipsang, the 2014 champion, was three seconds back with Ethiopia's Lelisa Desisa third in 2:11:32.

Kamworor, 24, settled for second in 2015 behind Kenyan Stanley Biwott after being overtaken late on. Kipsang, 35, won in Tokyo earlier this year but quit after 30km in September's Berlin Marathon.

Expanded security lined the route of the world-famous race, which saw an estimated 50,000 runners from more than 125 nations compete over 42.195km across the city streets.

New York City Mayor Bill de Blasio said the event being staged as planned was "a terrorist's worst nightmare" for bringing together people from a variety of cultures with resilience despite the recent deadly attack.

He said: "Look at that unity. Look at that example - live and let live. It's everyone getting together for a common cause - it doesn't matter what background you are from. This event is life-affirming every year but this year more than ever."

It certainly was for Flanagan. She had suffered a stress fracture in her back in the winter that forced her out of the Boston Marathon and kept her away from running for 10 weeks.

In the interim, the daughter of Cheryl Bridges - who once held the marathon world record - took a vacation. She focused on her foster children. She brainstormed ideas for a second cookbook, following the success of her bestseller.

Keflezighi, who finished 11th in the men's race, said he had been texting and e-mailing Flanagan words of encouragement throughout the spring and summer.

"I just couldn't be happier for her," he said. "She deserves one of those, whether it's here or Boston."

NYTIMES, AGENCE FRANCE-PRESSE