The swimmer, who won two golds in 2008, will join a line-up of ex-soap actors and reality TV stars in the new series which starts on Sunday.
The Sun reported Adlington is one of a dozen celebrities taking part including Towie star Joey Essex, Westlife’s Kian Egan, snooker player Steve Davis, and Miss Great Britain Amy Willerton.
Also heading out to Australia are former EastEnder Laila Morse, TV presenter Matthew Wright, Emmerdale’s Lucy Pargeter and Alfonso Ribeiro who starred in The Fresh Prince of Bel Air opposite Will Smith.
The line-up is completed by former Strictly Come Dancing star Vincent Simone, TV presenter Annabel Giles and David Emanuel — best known for designing Princess Diana’s wedding dress.
Last year’s series was won by Charlie Brooks who plays Janine Butcher in EastEnders.
The show, hosted by Geordie duo Ant and Dec, starts on ITV on Sunday, Nov 17, at 9pm.