Athens Olympic double gold medalist Kosuke Kitajima wiped out his own national record in the 100-meter breaststroke en route to claiming victory at the short-course national championships Saturday.

News photoOlympic gold medalist Kosuke Kitajima swims to a new Japanese record of 57.95 seconds in winning the men's 100-meter breaststroke at the short-course national championships on Saturday.

Kitajima clocked a time of 57.95 seconds in the 25-meter pool as he beat back the competition, which included two foreign athletes at Tokyo Tatsumi International Swimming Center.

"It's been a long time since I enjoyed this sense of thrill. I had a great swim," said Kitajima, who improved his own mark by 0.28.

Kitajima touched the wall 1.36 seconds ahead of Ukrainian Oleg Lisogor, who took second in 59.31. Huges Duboscq of France was third in 59.55.

"I'm concentrating on having fun while I compete. It's back to the basics for me," Kitajima added.

Meanwhile, Reiko Nakamura of Nippon Sports Science University, who took the bronze medal in Athens, came just 0.41 shy of a short-course world record to win the women's 200 backstroke with a new national record of 2:04.03.

In the women's 800 freestyle, Ai Shibata, who won gold in Greece, blew away the field to win in 8:21.90.

Maiko Fujino erased the national short-course record in the women's 400 individual medley for the first time in 12 years after winning with a time of 4:34.51.

Yuko Nakanishi, who took home bronze in the women's 200 butterfly in Athens, rewrote the national record to win the same event in 2:04.71.

Tomomi Morita set a new short-course national mark in the men's 200 backstroke in 1:53.71, while Daisuke Hosokawa, who finished second in 1:45.50 in the men's 200 freestyle, also set a new Japanese mark.