Former Australian champion swimmer James Magnussen says he is ready to accept the challenge of taking performance-enhancing drugs to break a world record and collect a US$1 million reward.

The 32-year-old, who won 100m freestyle world titles in 2011 and 2013, is planning to come out of retirement and compete at the proposed "Enhanced Games", where banned substances will be allowed.

Founded by London-based Australian businessman Aron D`Souza in 2023, competitors would not be subject to World Anti-Doping Agency rules -- a concept that has been criticised as dangerous.

According to the Games website, all athletes taking part will get a base salary and prize winnings that "will be larger than any other comparable event in history".

Those who break a world record would receive US$1 million, with Magnussen, who retired in 2018, the first major name to take the bait in a bid to smash the 50m freestyle mark.

If he did so, it would not be officially recognised.

"If someone asked me to do this during my swimming career, my answer would have been completely different to what it is today as someone six years retired from sport," he said in a column for The Australian newspaper on Saturday.

"To be completely transparent, the money is a huge part. A $1.6m Australian dollars prize is hard to ignore. Retired athletes don`t have opportunities like this pop up every day."

Brazil`s Cesar Cielo has held the one-lap record of 20.91 seconds since 2009 when he set it wearing a streamlining high-tech "super-suit" that has since been banned.

Magnussen, who has a personal best of 21.52, said he would take no chances with his health.

"I want to be surrounded by the right doctors and the right medical support. I want to do it properly," he said.

"I want to do it methodically and scientifically to make sure any supplementation is not having any negative effects on my body long term.

"This is not for everyone and it is certainly not something for young athletes.

"But if this proves you can seriously improve performance scientifically and do it safely, then maybe it is an entertaining event for people to watch."

Backed by venture capitalists, the Games are set to include five core categories -- athletics, aquatics, gymnastics, strength and combat, according to its website. A time and venue for the first Games have yet to be announced.

"It`s time to pay the athletes and reward excellence. People like James deserve to earn millions for the extraordinary feats they have accomplished," D`Souza said on social media platform X in response to Magnussen`s interest.

Since the Enhanced Games concept was floated last year, reactions from the sporting world have been generally negative.

The Australian Olympic Committee has called the idea "dangerous and irresponsible".

Former English swimmer Sharron Davies, an Olympic silver medallist, asked on social media Saturday: "Why would we want to know who can cheat the most to win prizes?" BSS/AFP