Changes in breaststroke swimming performances in national and international athletes competing between 1994 and 2011 - a comparison with freestyle swimming performances We have compared the performance of chillers from the 1994-2011 period for swimmers at national level (Switzerland) against floats at international level (World Cup finals). Swimmers of both levels improved their performance over the years with the exception of the swimmers on the World Cup level over 50m of men in breast swimming.The difference between the sexes took over the time for the freestyle swimmers at a national level, but not for the Freestilschwimmer at an international level and the chest swimmers, where the sex difference remained constant over the years.
The difference between the sexes decreased with increasing route length. The whole work can be read below https://bmcsportscimedrehabil.biomedCentral.com/articles/10.1186/2052-1847-6-18