BERLIN - Double world champion Kate Ziegler of the United States broke her own 800-metre freestyle short-course world record on Sunday at a meeting in Essen, Germany -- her third world record in 48 hours.

Kate Ziegler smiles after winning the women's 400m freestyle event at the US Swimming National Championships in Indianapolis August 2, 2007. [Agencies]

Ziegler, 19, set a world record over 800 metres in the 25-metre pool with a time of eight minutes 8.00 seconds, according to the Web site of the SG Essen swimming club (www.sg-essen.de).

She beat the mark of 8:09.68 that she had recorded on Friday in the middle of a 1,500-metre race.

On Friday, Ziegler had first lowered the record in the 800, beating the mark of 8:11.25 held by France's Laure Manaudou, en route to a record in the 1,500 of 15:32.90, below Manaudou's 15:42.39.

Ziegler won the gold medal over both distances at the world championships this year in Melbourne.

Manaudou's 800 mark was recorded on December 9 2005 in Italy and the 1,500 record set on November 20 2004 in France.