Monday 29 July 2019 10:19, UK
Olympic champion Dalilah Muhammad set a new world record in the 400m hurdles at the US Championships on Sunday.
The 29-year-old clocked a time of 52.20, shaving 0.14 seconds off Yuliya Pechonkina's record that had stood since 2003.
Muhammad did it from lane four and in rainy conditions in Des Moines.
"I'm just shocked," said Muhammad. "I've been kind of hitting that time in practice and my coach was like 'there's no way you can't do it'."
Muhammad is the reigning Olympic champion, having topped the podium in Rio in 2016.
