Australian Brett Hawke has overseen the fastest freestyle in history as he braces for backlash while coaching drug-taking swimmers.

The dual Australian Olympian has joined Enhanced Games as head swim coach for the multi-sports event with no drug testing.

Under Hawke's guidance at a trial on February 25, Greek swimmer Kristian Gkolomeev bettered the existing 50m free world record.

Three weeks into a 12-week enhancement program, Gkolomeev - who finished fifth in the event at the past two Olympics - clocked 20.89 seconds at the Greensboro Aquatics Centre in North Carolina.

Brazilian Cesar Cielo (20.91) has owned the legal world record since the supersuit era of 2009 when he was coached by Hawke.

The Bulgarian-born Gkolomeev, who raced for Greece at four Olympics, was given $US1 million in prizemoney by Enhanced Games organisers for bettering the official benchmark.

"I didn't make any money in Greece; from the last two Olympic Games, I got fifth and nothing really changed," Gkolomeev told AAP in an interview in Las Vegas .

"One successful year at the Enhanced Games, I can probably make as much as I would have made in almost 10 careers."

Gkolomeev only attended the February trial, which Enhanced Games organisers say used Olympic timing systems, as support for James Magnussen.

The Australian entered his first-ever enhancement phase in the US on limited preparation.

Ten weeks into his program, he clocked a best time of 22.73. In his clean 15-year international career, the now 34-year-old's personal best was 21.52 in 2013.

Hawke was in no doubt that with lessons learnt and tweaks to Magnussen's enhancement program ahead of the inaugural games in Las Vegas on May 21-24 next year, the triple Olympic medallist will thrive.

And the former Australian 50m freestyle record holder and five-time national champion was preparing for backlash to his involvement in Enhanced Games.

"I look at this as groundbreaking, revolutionary, for sure," he said.

"You'd be silly not to think that people aren't going to be opposed to it.

"But we're outside the scope of the Olympic Games and World Aquatics, we're not competing in that space.

"The backlash will be there, I knew that from the start.

"But I hope people go in with an open mind and really look at this and do the research that I've done."

Hawke said he remained an advocate for clean sport "on the Olympic side".

"I would never want an athlete to participate at the Olympic Games and be cheating," he said.

"And unfortunately, I think that is happening in this day and age.

"But what I'm doing over here with the Enhanced Games is something completely different."

Hawke, who has coached in the United States since 2006, said his interest was piqued when hearing Australian entrepreneur and Enhanced Games president Aron D'Souza on the Joe Rogan podcast.

"I'm pretty open minded and progressive with my thoughts and I like to listen to people's arguments and I thought they were pretty compelling," he said.

As the Sydney-born 49-year-old researched, his long-standing view changed.

"Initially, and I think that's the operative word here, we're taught that performance enhancing drugs are bad and all we hear about them is the abuse of them," Hawke said.

"That's all I knew so of course that's what I initially thought, people are going to be abusing drugs.

"And that is certainly not the case at all and I've learned over time it's a pretty naive view on this.

"But yeah, initially I had the same reaction as anyone else until I did my research, until I started asking questions."

This AAP article was made possible by support from the Enhanced Games.