NEW YORK, Nov 5 - Ultra marathon man Dean Karnazes completed his goal of running 50 marathons in 50 successive days at Sunday's New York City Marathon.

The 44-year-old from San Francisco ended his quest on a high note, clocking the fastest time, three hours 36 seconds, of his unusual journey through the 50 U.S. states.

"I feel really good. I feel like I got a little stronger over the 50 days," Karnazes told Reuters.

Karnazes said he had reached a goal of raising $100,000 for Karno Kids, a foundation he started to benefit youth fitness programmes.

Eight of the marathons he ran were 'live' events, running in an official field such as he did in New York. The other 42 were re-created races along the route of a particular state's marathon.

Karnazes, author of "Ultramarathon Man: Confessions of an all-night Runner", said he felt energised by the New York crowd.

"I definitely got a lot of energy from everyone cheering along the course and from other runners," he said. "I was talking to people for all 26.2 miles."

Besides the elite field of championship runners, a number of other celebrities also participated in the race.

Seven-times Tour de France champion Lance Armstrong clocked 2:59:36, the 869th fastest time among the 38,368 official entrants.

World renowned mountaineer Ed Viesturs ran the distance in 3:15:25; former U.S. gymnast Shannon Miller, winner of seven Olympic medals, clocked 4:17:46; model Kim Alexis was timed in 4:39:48, and Arkansas Gov. Mike Huckabee finished in 5:33:42.