Shalane Flanagan became the first United States woman to win the New York City Marathon in 40 years, and even she can't quite believe it. Flanagan, 36, has competed in the Olympics four times, and her lifetime of training paid off on Sunday. Flanagan went on "Good Morning America" to talk about the win on Monday, and even to her, it seemed like it was surreal.

"I've been dreaming of a moment like this since I was a little girl," Flanagan said. "All athletes have these dreams and these visions and it's what motivates us to get out the door to train hard. I visualized a moment like this and so I was trying to soak it up, but I was also running a little terrified that I was going to get caught. It really is a dream sensation."

No one, however, was going to beat Flanagan on Sunday, who was running for more than herself in her eyes. Throughout the race, she said she was thinking: "'I really want to bring a smile to New Yorkers' faces today,' and I'm so happy that I could."

Flanagan raced in the 2013 Boston Marathon that ended with bombs detonating near the finish line, and after the recent terror attack in New York, that was also on her mind. However, the reasons for Flanagan running aren't all altruistic: She also said that she just does it because it makes her a "better person."

Flanagan said she was hoping to put a smile on New Yorkers' faces.  USATSI

Flanagan talked to ESPN's Bonnie D. Ford in April about the end of her career, and it raises the question about whether or not this victory may be her swan song. "How my career ends is super important to me,'' she said in the interview after missing the Boston Marathon, her hometown race. "It doesn't mean I'm going to win a major, but at least I'm going to try to win a major marathon in the U.S., and I need at least two more events."

It seems like winning a major may push her timetable up a bit, but the 36-year-old won't stop running, whether it's for herself, a major or a city. This win was meaningful in a lot of ways, and some of them were bigger than Flanagan.