What does WR stand for?

She turned under world record time after the butterfly then fell off the pace on backstroke before recovering strongly with impressive breaststroke and freestyle legs to clock 4mins 22.

Fellow South African Darian Townsend, who beat Phelps in the 200m individual medley in Berlin with a new world record of 1:51.

The Merseyside swimmer, 19, led Great Britain's charge with silver in the women's 100 metres freestyle before touching in third behind a world record swim from Holland's Hinkelien Schreuder in the 100m individual medley.

Summary: Usain Bolt broke his own world record to win the 100 metres at the World Championships in Germany in emphatic style.

Michael Phelps ended on a golden note as the United States rounded out the swimming World Championships' world record total at a staggering 43 with a medley relay triumph.

SWIMMING: Michael Phelps has set his sights on breaking the 50-second barrier after setting a new world record in the 100metres butterfly.

Summary: World record holders often seek recognition for the feats, but staking a place in the Guinness Book of World Records may prove more of a challenge for the longest-held political prisoner who broke World record holders often seek recognition for the feats, but staking a place in the Guinness Book of World Records may prove more of a challenge for the longest-held political prisoner who broke the record Friday.

Great Britain's Joanne Jackson said she'd been "blown away" to have set a new women's 400 metres freestyle world record of four minutes 00.