2019 World Athletics Championships – Women's 400 metres

The 2019 season saw only four women break 50 seconds. World leader Shaunae Miller-Uibo did it three times. Salwa Eid Naser broke it once, coming back against a challenge from Aminatou Seyni. Naser was consistently under 51, five times during the 2019 IAAF Diamond League season. Seyni was not allowed to compete in the 400 metres because of the new IAAF testosterone rule.[2] Shericka Jackson was the fourth to break 50 at the Jamaican championships.

Those athletes were the ones to watch in the final. With multi-toned hair, the tall Miller-Uibo started like she meant business, gaining on the stagger against defending champion Phyllis Francis to her outside and by the backstretch, Francis had already made up the stagger on Justyna Święty-Ersetic to her outside. In the center of the track, Naser had also already made up the stagger on Wadeline Jonathas to her outside. Miller-Uibo and Naser hit the 200 meter split marks virtually even. Through the final turn, Naser was moving faster, opening up 4 metres by the home straight. The first time Miller-Uibo was able to see Naser, she was already behind. That final straight is usually Miller-Uibo's territory. She began stretching out her long strides to reel Naser in. Miller-Uibo steadily gained on Naser, pulling in three metres, but it wasn't enough. Miller-Uibo set a new personal best, 48.37, which became the #6 400 metre race of all time. Naser beat her with 48.14, the #3 400 of all time. Jackson held off the American duo of Jonathas and Francis, all personal bests under 50 seconds. Like all previous top 10 women's races, there were two close competitors battling to the line.

Before the competition records were as follows:[3]

Record	Perf.	Athlete	Nat.	Date	Location
World	47.60	Marita Koch	GDR	6 Oct 1985	Canberra, Australia
Championship	47.99	Jarmila Kratochvílová	TCH	10 Aug 1983	Helsinki, Finland
World Leading	49.05	Shaunae Miller-Uibo	BAH	27 Apr 2019	Gainesville, United States
African	49.10	Falilat Ogunkoya	NGA	29 Jul 1996	Atlanta, United States
Asian	49.08	Salwa Eid Naser	BHR	20 Jul 2018	Monaco
North, Central American and Caribbean	48.70	Sanya Richards-Ross	USA	16 Sep 2006	Athens, Greece
South American	49.64	Ximena Restrepo	COL	5 August 1992	Barcelona, Spain
European	47.60	Marita Koch	GDR	6 Oct 1985	Canberra, Australia
Oceanian	48.63	Cathy Freeman	AUS	29 Jul 1996	Atlanta, United States

The following records were set at the competition:

Record	Perf.	Athlete	Nat.	Date
World Leading	48.14	Salwa Eid Naser	BHR	3 Oct 2019
Asian
Bahraini
North, Central American and Caribbean	48.37	Shaunae Miller-Uibo	BAH
Bahamian

The event schedule, in local time (UTC+3), was as follows:[4]