Judo superstar and Democratic Party of Japan lawmaker Ryoko Tani said Friday she will retire from judo and pursue her political career to improve the nation's sports environment.

"I've decided to step back from the front line of competition," Tani, 35, a two-time Olympic gold medalist who won her Diet seat in the July 11 Upper House election, told reporters in Tokyo. Party sources revealed that she told a senior DPJ member she couldn't pursue both careers because of time constraints and other reasons.

Tani, widely known by the nickname Yawara-chan, which comes from the title character of a popular judo manga, won gold in the 48-kg division at the 2000 Sydney and 2004 Athens Olympic Games. She is currently serving as chief of the DPJ's intraparty group comprising lawmakers from the sports field.

Her political career started with a request from DPJ bigwig Ichiro Ozawa in March to run for the Diet.

When Tani announced in May she would enter the July Upper House race, she expressed her eagerness to win another gold medal at the 2012 Summer Olympics in London.

At the time, Ozawa was still the party's secretary general. He resigned the following month. He said Tani's decision was an incredible boost for the DPJ, saying, "her self-discipline and strong willpower are lacking in modern Japanese society."

The DPJ at the time was getting hammered by money scandals involving Ozawa and former Prime Minister Yukio Hatoyama.