New Zealander Sarah Ulmer set a women's 3km individual pursuit cycling world record on Saturday and 24 hours later she bettered her own mark.

Ulmer beat Australian Katie Mactier for the gold medal, clocking 3:24.537 to shave 1.863 seconds off her own mark.

"The track is fast. During the race I never watch the time. I didn't know if I would break the record but I knew that I was trying hard and that it was a very fast race," said Ulmer, fourth in the discipline at Sydney Olympics.

At this year's World Championships in Melbourne, Australia, Ulmer broke the world record of women's 3km individual pursuit.

Born in Auckland, the 28-year-old New Zealander began her first race with a high school team.

"Because the cycling is fun, and I can figure out for myself most of my own training, with the help of my dad (Gary Ulmer) and my boyfriend Brendon Cameron," said Ulmer, who looked like a twittering bird during today's news conference.

In her opinion, her father was the most influential person who dragged the little girl to Manukau Club when she was 15 years old. "For he has been a cyclist and has done the cycling," said Ulmer, whose idol is Susan Devoy.

"Devoy was a wicked sportsperson to follow and look up to when I was trying to rip into it," she said, who is a member of TDS Women's Cycling Club, of United States.

Educated in Auckland University and being sports ambassador of New Zealand, Ulmer likes to cruise with her dogs, watch movies and videos, and learn French.

"Track cycling isn't straightforward at all. To be at your best - mentally, physically, spiritually - for just one day is a rare occurrence, and to plan for it and pull it off is even rarer," she said.

"If you're going to win the Olympic Games, you can't really look at one person being a threat, but rather the entire field, regardless of who you are racing," she added.