Dhaka, May 4 -- American Katie Ledecky shattered her own 800 metres freestyle world record in 8 minutes 4.12 seconds at the Tyr Pro Series meet in Fort Lauderdale, Florida, finding her best form heading into the world championships.

Ledecky bettered her previous mark of 8:04.79 set nearly a decade ago at the Rio Games that many thought would outlast her career and she pounded her fists on the water in an emotional celebration after seeing her time.

It was the sixth time that Ledecky had set a new mark in the event. She took the record from Rebecca Adlington in 2013.

The record-breaking swim capped an extraordinary series of performances for the 28-year-old, the most decorated female Olympic swimmer, who posted her second-fastest 400m f...