Australian four-times Olympic gold medallist Ariarne Titmus has retired from competitive swimming at the age of 25, ending a stellar career that featured one of the sport’s great rivalries with American Katie Ledecky.

Titmus confirmed her decision on Thursday, bowing out as one of Australia’s most decorated athletes with eight Olympic medals and four world titles.

The decision came as a shock to her nation, and the swimming world in general, as she had long planned a return to the pool to chase more Olympic glory at Los Angeles 2028.

“A tough one, a really tough one but one that I’m really happy with,” she said of her decision in a video on social media.

“I love swimming, I’ve always loved swimming. It’s been my passion since I was a little girl.

“But I guess I’ve taken this time away from the pool and realised some things in my life that have always been important to me are just a little bit more important to me.”

Race of the century

Titmus won her third individual Olympic gold medal in a 400m freestyle final dubbed “the race of the century” at the Paris Games when she beat Ledecky and Canada’s Summer McIntosh to defend her title.

After Paris, she resolved to take a year off from competing and training to recharge, electing to skip the world championships in Singapore and instead cover the meet as a TV commentator.

But the return to the pool never materialised.

Titmus had undergone surgery to remove benign tumours from her ovaries eight months before Paris and she said the health issue had reminded her about having a life outside swimming.

“Delving more into those health challenges, I’ve had to think about what’s most important to me,” said Titmus, who retires as the 200 freestyle world record holder.

“Beyond swimming I’ve always had goals in my personal life.

“More than anything I’m excited for what’s next.”

The face of Australian swimming at the last two Olympics, Titmus’s retirement robs the national team of an inspirational leader who did much to restore the country to superpower status in the sport after a lean decade.

Born in Tasmania, Titmus moved to Queensland in her early teens to be trained by elite coach Dean Boxall.

Earning the nickname ‘Terminator’ after sweeping the 400 and 800 freestyle titles at the 2018 Commonwealth Games on the Gold Coast, she then announced herself to the swimming world by beating Ledecky in the 400 at the 2019 world championships.

Two years later, her swim to reel in Ledecky and snatch her 400 crown at the Tokyo Games became instant swimming folklore, along with Boxall’s manic celebrations in the stands.

The successful defence of her title in Paris made her the first Australian woman to go back to back in an individual swimming event since Dawn Fraser in the 1960s.

Titmus also bagged two silvers and a relay gold at Paris, including her runner-up finish behind Ledecky in a thrilling 800 freestyle final.

She always said Ledecky, the ‘GOAT’ of women’s swimming, made her a better rival, but as intense as the rivalry was there was only mutual admiration, hugs and kind words outside the pool.

The American great was among those congratulating Titmus on her career after the retirement announcement.

“An outstanding competitor, champion and person!” she wrote on Titmus’s Instagram feed.