Simone Biles: Olympic champion expects Tokyo 2020 to be last Games

World champion Simone Biles says Tokyo 2020 will be her final Olympics as her body is "falling apart".

Biles, 22, dominated the 2016 Olympics with four golds and became the first woman to win four World Championships all-around titles in 2018.

The American, who has won 14 World Championship gold medals, says minor injuries are taking a toll.

"I am in pain most of the time but it kind of feels right as if not, it is like you could do more," she said.

"I definitely plan for the Tokyo Olympics to be my last.

"I feel like my body's gone through a lot and it's kind of just falling apart - not that you can actually tell but I really feel it a lot of the time."

Texas-based Biles has 20 World Championships medals in all.

In addition to the bronze she earned on the beam at Rio 2016, her four gold medals from the Games set an American record for most gold medals in women's gymnastics at a single Olympics.

She became the first quadruple gold medallist in women's gymnastics at a single Games since Romania's Ecaterina Szabo in 1984.