[1] U.S. swimmer Katie Ledecky set a new world record to defend her Olympic title in this event and to successfully complete a distance freestyle treble at a single edition for the first time, since Debbie Meyer did so in 1968.

[2] Dominating the race from the start, Ledecky quickly dropped two seconds under a world-record pace, as she pulled further away from the field to overturn her own existing standard with a gold-medal time in 8:04.79.

[5][6] Meanwhile, Kapás faded down the stretch to earn a bronze in 8:16.37, two tenths of a second short of Carlin's time.

Outside the 8:20 club, Australia's Jessica Ashwood (8:20.32) and Ledecky's teammate Leah Smith (8:20.95), bronze medalist in the 400 m freestyle, picked up the fifth and sixth spots respectively, finishing 63-hundredths of a second apart from each other.

[8] Ledecky also overturned the existing Olympic record in 8:12.86 to top the field of twenty-seven swimmers in the prelims, taking 1.24 seconds off the standard set by Great Britain's Rebecca Adlington in a since-banned high-tech bodysuit in Beijing eight years earlier.