Four-time Australian Olympic gold medallist Ariarne Titmus has announced her retirement from swimming aged 25, saying it was a “tough” decision.

“I’ve always loved swimming, it’s been my passion since I was a little girl,” Titmus said in an Instagram video on Thursday.

She took a break after last year’s Paris Olympics and “realised some things in my life that have always been important to me are just a little bit more important to me now than swimming.”

Titmus is a two-time Olympic champion in the 400m freestyle, triumphing in Tokyo in 2021 and in Paris last year. She also won 200m freestyle gold in Tokyo and was part of the Australia team that won 4x200m freestyle relay in Paris.