Urged on by a vocal standing room only crowd, Michael Phelps closed out his weekend at the Maryland Swim Championships by setting the U.S. record in the 200-yard butterfly at the U.S. Naval Academy on Sunday.

Competing as a member of the North Baltimore Aquatic Club, located 48 kilometres from Annapolis, the 14-time Olympic gold medallist touched home in a time of one minute, 39.65 seconds.

His previous record time was 1:39.7, set March 3, 2006 at the South Texas American Short Course Championships in Austin.

The record came one day after Phelps had missed setting the American record in the 200 individual medley by a half-second. Though he failed to break Ryan Lochte's record, Phelps did set a personal best in the event.

Phelps won both the 2004 and 2008 Olympic gold medal in the 200-metre butterfly.

The crowd noise on Sunday let him know that he was swimming at a record pace late in the race.

"When the crowd starts yelling like they were, you know something good is happening," he said. "Whenever they get behind it and get more excited and louder, you kind of feel the energy and gain adrenaline. Being able to have that was definitely helpful. It makes it so much more exciting. You really can hear them on every stroke."

Phelps was primed to set the U.S. record in the shorter course race, measured in yards rather than metres.

"I tried to find out what my splits were when I broke the record back in '06 and just wanted to see what I could do tonight," Phelps said. "I wanted to try and go out and take a shot at it. Coming off the last turn I wanted to stay under as long as I could. That was clearly the difference."

Phelps had opened the three-day meet with a victory in Friday's 400-yard individual medley, but was more than three seconds off the American record. After that race, his disappointment was obvious.

"On Friday, I let other things stand in my way and I wasn't able to compete how I wanted to," Phelps said. "[Saturday] night and [Sunday] I wanted to come here and put all that behind me and just come in and race how I know how to race."

Phelps is preparing for the 2012 Summer Olympics and said the two years will "fly by." His next competition will be at Ohio State University during the first weekend in April.

"There are a lot of things yet to be done," Phelps said. "This shows that with more time and training I can get faster. I am not in the best shape athletically right now and not in the best swimming shape. But being able to do what I did the last two weeks shows anything is possible when I am prepared."

It was the third win of the weekend for Phelps, swimming competitively for the first time in seven weeks.