Trickett, 24, had spent the last few months contemplating her future following her disappointing display at the World Championships during July in Rome, the first time she did not return home with a gold medal in five years, winning a silver and two bronze.

She said: "It's something that I've been thinking about for almost a year now, and after much consideration and speaking with my family and close friends I know that I am ready to move on to the next stage of my life and career."

Trickett won six medals over two Olympics in Beijing and Athens as well as eight gold, three silver and four bronze medals from four World Championships.

Trickett won her only Olympic individual title last year in Beijing with gold in the 100 metres butterfly.

Her other Olympic titles came in the 4x100m freestyle relay in Athens in 2004 and the 4x100m medley relay in Beijing.

Trickett said: Swimming is such a great sport to be involved with and has been a huge part of my life for such a long time.

"I would like to thank everyone for their fantastic support throughout my career, especially my family and coaches Stephan Widmer and Grant Stoelwinder."

The Australian's final competitive appearance saw her set a new short-course world record in the 100m freestyle in August.

Trickett said: "I sincerely believe I left at a great point for me.

"I don't feel like I was getting slower and don't feel like I was getting any less competitive at all.

"I'm retiring on my own terms.

"I'm not being forced to."

She had considered retiring immediately after Rome but decided, however, to take some time away from the pool to make a considered decision before giving up the chance to win Olympic gold in her favourite 100m freestyle in London.

Trickett said: "Ultimately if I was to swim on that would probably be the only reason for me to swim on.

"I can't justify doing that for four years and then maybe walking away and not having achieved that.

"I've asked myself that question, 'Am I okay with not winning an Olympic gold medal in the 100m freestyle?'

"And the answer was 'I am okay with that'.

"When you say that, that means you're ready to move on."

Trickett will now concentrate on pursuing a career in the media.


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November 2009: Trickett will make decision on London 2012 next month