South Korean speed skater Lee Sang-hwa broke her own world record in the women's 500 meters for the second time in under a week on Friday in the United States.

Lee won the women's 500ｍ in 36.57 seconds at the second leg of the International Skating Union (ISU) Speed Skating World Cup being held in Salt Lake City, Utah, improving her own record by 0.17 of a second.

At the first World Cup event in Calgary, Canada, last Saturday, Lee won the 500ｍ in 36.74 seconds, 0.06 seconds faster than her previous world record set in January this year.

The 24-year-old is the reigning Olympic champion in the 500m and her record-breaking form makes her the favorite to repeat as the gold medalist when Russia's Sochi hosts the 2014 Winter Games next February.

Wang Beixing of China came in second place behind Lee in Salt Lake City with 36.85 seconds, followed by American Heather Richardson at 36.97 seconds.

Lee dominated the 500ｍ during the previous World Cup season from November 2012 to March of this year, winning nine races en route to capturing the overall title.

In World Cup events, skaters earn 100 points for each win and 150 points for a victory at the season-ending World Cup Final.

So far this season, Lee has won all three 500ｍ races in the World Cup circuit -- twice in Calgary and once in Salt Lake City -- for 300 points, 80 points better than Wang of China and Jenny Wolf of Germany. (Yonhap News)