King was disqualified just before the halfway point while on target for a personal best time.

Rio 2016
Olympic marathon silver medallist Kirwa suspended for doping
22/05/2019 AT 11:20

The rules of race walking requires the athlete to straighten their supporting leg as soon as it touches the ground - and to keep it straight until it has passed under the body.

There are officials on hand throughout the course to watch race walkers' form. They can issue a yellow paddle - which acts as a warning - or a red paddle if they are convinced the athlete is violating the rules.

Rio 2016
Police raid home of Brazil Olympics chief over Rio 2016 vote buying
05/09/2017 AT 15:31
Rio 2016
Schippers: Rio didn’t turn out as I had hoped
22/08/2016 AT 17:05