Athletics-American Muhammad breaks own world record to win 400m hurdles

American Dalilah Muhammad broke her own world record to win the women's 400 meters hurdles at the world athletics championships with a time of 52.16 seconds on Friday.

Muhammad had previously set the record by running 52.20 at Des Moines in the United States in July. Her compatriot Sydney McLaughlin was second in 52.23 seconds.