Women's 400 metres world record progression explained

The first world record in the 400 m for women (athletics) was recognized by the International Amateur Athletics Federation, now known as the World Athletics, in 1957.

To June 21, 2009, the IAAF has ratified 27 world records in the event. Their 2009 record progression list, however, lists 26 records.^[1]

Record progression 1957–1974

Time	Auto	Athlete	Location of race	Date
57.0y		Marlene Mathews	Sydney, Australia	6 January 1957
57.0y		Marise Chamberlain	Christchurch, New Zealand	16 February 1957
56.3y		Nancy Boyle	Sydney, Australia	24 February 1957
55.2		Polina Lazareva	Moscow, Soviet Union	10 May 1957
54.0		Mariya Itkina	Minsk, Soviet Union	8 June 1957
53.6		Mariya Itkina	Moscow, Soviet Union	6 July 1957
53.4+		Mariya Itkina	Krasnodar, Soviet Union	12 September 1959
53.4		Mariya Itkina	Belgrade, Yugoslavia	14 September 1962
51.9		Shin Geum-Dan	Pyongyang, North Korea	23 October 1962
51.7	51.72	Nicole Duclos	Athens, Greece	18 September 1969
51.7	51.74	Colette Besson	Athens, Greece	18 September 1969
51.0	51.02	Marilyn Neufville	Edinburgh, Scotland	23 July 1970
51.0	51.08	Monika Zehrt	Paris, France	4 July 1972
49.9		Irena Szewińska	Warsaw, Poland	22 June 1974

(y) indicates time for 440 yards (402.34 metres), ratified as a record for this event
(+) plus sign denotes en route time during longer race

The "Time" column indicates the ratified mark; the "Auto" column indicates a fully automatic time that was also recorded in the event when hand-timed marks were used for official records, or which was the basis for the official mark, rounded to the 10th of a second, depending on the rules then in place.

Record progression from 1975

From 1975, the IAAF accepted separate automatically electronically timed records for events up to 400 metres. Starting January 1, 1977, the IAAF required fully automatic timing to the hundredth of a second for these events.^[1]

Riitta Salin's 50.14 from 1974 was the fastest recorded result to that time.

Time	Athlete	Location of race	Date
50.14	Riitta Salin	Rome, Italy	4 September 1974
49.77	Christina Brehmer	Dresden, East Germany	9 May 1976
49.75	Irena Szewińska	Bydgoszcz, Poland	22 June 1976
49.29	Irena Szewińska	Montreal, Canada	29 July 1976
49.19	Marita Koch	Leipzig, East Germany	2 July 1978
49.03	Marita Koch	Potsdam, East Germany	19 August 1978
48.94	Marita Koch	Prague, Czechoslovakia	31 August 1978
48.89	Marita Koch	Potsdam, East Germany	29 July 1979
48.60	Marita Koch	Turin, Italy	4 August 1979
48.16	Marita Koch	Athens, Greece	8 September 1982
47.99	Jarmila Kratochvílová	Helsinki, Finland	10 August 1983
47.60	Marita Koch	Canberra, Australia	6 October 1985

Notes and References

Web site: 12th IAAF World Championships In Athletics: IAAF Statistics Handbook. Berlin 2009. . IAAF Media & Public Relations Department . Monte Carlo . Pages 546, 641 . pdf . 2009 . August 2, 2009 . https://web.archive.org/web/20110629134819/http://www.iaaf.org/mm/document/competitions/competition/05/15/63/20090706014834_httppostedfile_p345-688_11303.pdf . June 29, 2011 .