Hammer retires as one of the United States' most successful cyclists, having also earned 15 World Championship medals during her career.

She made her first appearance at the Olympic Games at Beijing 2008 and claimed her first medals four years later at London 2012, coming second in the team pursuit and omnium.

Her medals ended a 12-year drought for the US in track cycling at the Olympics.

Hammer repeated the feat again at Rio 2016, finishing behind Britain’s Laura Kenny in the omnium.

The American has announced her intention to continue working in track cycling, as she becomes the director of coaching at Performance United, a training facility in Colorado Springs.

"I’m really excited to continue my journey of promoting track cycling and women’s cycling in my new role," Hammer said in a statement.

"My primary focus will be to share and implement my knowledge with incoming athletes and coaches so they don’t have to learn it all on their own."

Hammer also earned eight world titles on the track during her career, including a dominant run in the women’s individual time trial.

She won the event five times from 2006, as well as ending as the silver medallist on a further two occasions.

The Californian rider also won the women’s omnium world title in 2013 and 2014, while she was part of the squad that claimed the US' first ever women’s team pursuit gold at the World Championships in 2016.

Hammer also earned gold in the omnium at the Toronto 2015 Pan American Games, while she retires holding the individual pursuit world record.