Olympic Champion Dalilah Muhammad shattered the 400m hurdles world record on the final day of the US National Championships in Iowa with a superb display.

She broke one of the longest-standing records in women’s athletics by taking more than a tenth of a second off a record that had stood unbeaten for 16 years. The 29-year-old clocked 52.20 seconds to beat Russian Yuliya Pechonkina’s previous mark of 52.34.

Despite the rain, she performed her best, smiled as she slowed down to a jog and then to a walk to complete stop. Then she clapped and bent over. “I am just shocked,” Muhammad said after her historic win. My coach kept telling me the record was there. I just had to trust that and go for it. I wanted it so bad I knew I had to go out there and prove myself.”

19-year-old Sydney McLaughlin was second clocking 52.88 seconds and Ashley Spencer came third in 53.11. All the first three athletes got qualified for the World Championships in Doha in September where they will be joined by reigning world champion Kori Carter.