Australian Richard Thompson has won the 513km three-day ultra triathlon world championship in Kona, Hawaii, before he announced it would be his last event as a triathlete.

The 33-year-old led after each day of racing to complete the enduro in a time of 22hrs 09mins 26sec and claim victory by almost one hour.

Day one consisted of a 10km and 144km bike ride, which Thompson finished in 6:52.57 to be seven minutes clear of his closest challenger.

Read Next He backed that up with a 8:20.03 bike ride to cover 274km on Saturday and extend his advantage to more than 20 minutes.

The final day's 84km double marathon was a mere formality for the Queenslander who crossed the finish line in a time of 6:56.24.

After the race Thompson told T:Zero Multisport that he would no longer compete and switch his focus to coaching and spending more time with his family.

Thirty men competed in the Ultra Man world championships while Canadian Tara Norton won the 10-strong women's event.