This is the progression of world record improvements of the 400 metres W40 division of Masters athletics.
Key
HandAutoAthleteNationalityBirthdateLocationDate52.50Geisa Aparecida Coutinho1 June 1980Bragança Paulista9 April 202153.05 Maria Magnolia Figueiredo11 November 1963Bogotà11 July 200453.68 Sara Montecinos8 March 1954Cali20 March 199455.38Maeve Kyle6 October 1928Edinburgh22 July 1970
References
Masters Athletics 400 m list