World record progression 400 metres freestyle : ウィキペディア英語版
World record progression 400 metres freestyle
The first world record in the men's 400 metres freestyle in long course (50 metres) swimming was recognised by the International Swimming Federation (FINA) in 1908. In the short course (25 metres) swimming events the world's governing body recognizes world records since 3 March 1991. ==Men==