The men's 400 metre freestyle competition of the swimming events at the 1973 World Aquatics Championships took place on September 6.

Records Prior to the competition, the existing world and championship records were as follows.

The following records were established during the competition:

Date Event Name Nationality Time Record 6 September Heat Brad Cooper 4:02.38 CR 6 September Final Rick DeMont 3:58.18 WR

Results

Heats 27 swimmers participated in 4 heats. Rank Heat Lane Name Nationality Time Notes 1 1 - Brad Cooper 4:02.38 Q, CR 2 3 - Bengt Gingsjö 4:04.35 Q 3 4 - Rick DeMont 4:04.77 Q 4 1 - Anders Bellbring 4:05.77 Q 5 1 - Andreas Apel 4:06.13 Q 6 3 - Tim Shaw 4:06.57 Q 7 4 - Werner Lampe 4:07.01 Q 8 2 - John Kulasalu 4:09.32 Q 9 3 - Arnaldo Cinquetti 4:09.37 10 4 - Wilfried Hartung 4:10.90 11 3 - Deane Buckboro 4:11.72 12 2 - Vladimir Mikheyev 4:13.79 13 4 - José Namorado 4:14.37 14 4 - G Castillo 4:15.22 15 4 - Mark Treffers 4:15.81 16 2 - Dusan Grozaj 4:16.23 17 2 - Paul Jouanneau 4:18.19 18 1 - Marc Lazzaro 4:18.43 19 3 - Leonid Dragunov 4:18.79 20 2 - Michael Ker 4:20.10 21 2 - Ali Gharbi 4:20.18 22 4 - Alberto Vivoni 4:22.02 23 3 - Csaba Tóth 4:22.26 24 1 - Krasimir Enchev 4:24.53 25 2 - Francisco Canales 4:24.65 26 3 - Ali Kinawi 4:25.71 27 1 - Josy Wilwert 4:39.02

Final The results of the final are below. Rank Lane Name Nationality Time Notes 3 Rick DeMont 3:58.18 WR 4 Brad Cooper 3:58.70 CWR 5 Bengt Gingsjö 4:01.27 7 Tim Shaw 4:01.56 6 Anders Bellbring 4:04.36 2 Andreas Apel 4:04.92 1 Werner Lampe 4:09.83 8 John Kulasalu 4:14.62

References