Femke Bol breaks 41-year-old world women's indoor 400m record
The 22-year-old, competing at the Dutch national championships in Apeldoorn, bettered the 49.59sec of Czech runner Jarmila Kratochvilova in March 1982.
Bol, a world and Olympic 400m hurdles medallist, had also set a world best of 36.86sec in the rarely-run 300m hurdles in Ostrava last year.
"It was because of all the fans here that I ran this record," Bol said after her race at the Omnisport arena.
"Never have I ever seen that many people here. When I crossed the line I knew that the record was mine, because of the noise that the crowd made."
Bol had dipped under 50 seconds for the first time indoors with 49.96 in Metz last weekend but on Sunday she took 0.7sec off that mark.
She got a typical strong start and went through 200m in 23.63sec before surging over the finish line in 49.26, chased by Lieke Klaver who was second in 50.34.
Bol had given an indication of her impressive form two weeks ago when she clocked the fastest women's indoor 500m ever with a time of 1min 05.63sec at the Boston Indoor Grand Prix.
She became the first woman to break 1:06 at the distance, breaking the previous world best of 1:06.31 set by Russian Olesya Krasnomovets-Forsheva in January 2006.
Bol won European titles last year in the 400m hurdles, 400m flat and 4x400m relay.
She also won 400m hurdles silver at the World Championships in Eugene which followed bronze at the Olympic Games in Tokyo in 2021.