Cathy Freeman bent down to tie her lace and the flash of silver that appeared in Rick MacDonald's binoculars confirmed the rumours: Australia's great hope was wearing the suit for the race that would define the 2000 Sydney Olympics.

MacDonald relayed the message to those who had worked on the near three-year long Nike Swift Suit project and were next to him among the 112,000 spectators at the Olympic Stadium. Then he sounded a note of caution. "What if she doesn't win?"

"I hadn't even thought about that," suit designer Edward Harber told Stats Perform News 20 years on.

"She's in this crazy suit; what if she doesn't win?"

They need not have worried. Freeman, the face of those Games and an athlete of Aboriginal descent who became Australia's symbol of unity, stormed to 400 metres gold to delight the Sydney crowd on September 25, 2000.

"It was just this moment in the stadium of this absolute wall of sound," Harber recalled. 

"During the race, you almost felt like she couldn't not win because of the sound."

Just like Michael Johnson and his gold shoes in Atlanta, and Mo Farah's 'Mobot' on London 2012's Super Saturday, Freeman's victory provided one of the most iconic moments in Olympic history, and not just because it was a home gold.

The image of Freeman, donned in a unique green, silver and yellow all-in-one suit complete with hood, remains vivid two decades on.

---

Harber was designing clothing for the United States and British military in the late 1990s when he was hired by Nike to find a way of improving an athlete's performance in order for them to run at maximum velocity.

He and MacDonald identified aerodynamics and the reduction of drag as the key element so they, along with Len Brownlie and Chester Kyle - two experts in the field - set about designing a suit that was composed of different fabrics for different parts of the body.

"The reason every part of her body was covered up was to reduce drag," Harber explained.

"The hood was key. You would never see a speed skater skating without a hood. If you've got hair, you're slowing yourself down. You see runners with big hair and you're like, 'What are you doing?'

"You would never see a cyclist do that or a skater but it was a challenge for athletics, for running, because running has a look, it has a history, a heritage.

"What we were doing with that suit was challenging that heritage with science and saying, 'This is about winning, speed. This is what these athletes do in these sports. We're going to apply some of that thinking and engineering to running'."

Fabrics were tested on hand-sized, torso-sized, arm-sized and leg-sized cylinders in wind tunnels to determine which was most effective. Then, once Nike had sealed a deal to kit out the Australian team at the Olympics, came the possibility of Freeman wearing the suit.

"With Cathy, it was really about getting her comfortable with the suit, getting her to be at a point where she felt it was something she could consider," Harber added. "There was never a pressure for her to wear it, it was always going to be up to her."

---

It was not just the speed skaters at the 1998 Nagano Winter Olympics who provided Harber and his team with inspiration for their suit. Freeman's attire in that 400m final looks like something that might have been lifted from a Marvel comic.

And the reasoning for that was twofold.

"The superhero thing was obviously on my mind," Harber confirmed.

"During the project we would talk about the double advantage. We would say there's an advantage in having the science but there's also an advantage in the athlete understanding the science and having the psychological power of knowing that they're in this thing that no one else has got.

"The commentator on TV said that it looks like she was shrouding herself in this hood because the pressure was famously incredible, massive. I felt like when she put that hood up, she was definitely in somewhat of a bubble."

Freeman, who reported being able to hear air whistle past her ear during testing, wore the suit in the build-up to Sydney - on a rainy day in Gateshead - but did not have it on for either the heats or the semi-finals of the 400m at the Olympics.

But that famous night in September 2000, the suit went on, the hood went up and Freeman ran into the history books.

---

Given Freeman's glory and sport's obsession with marginal gains, it is somewhat surprising that her outfit did not spark a movement that saw the Swift Suit become widely adopted by athletes.

Freeman was the only athlete in Sydney to race in the suit with the hood up - meaning it was impossible to put an actual figure on its impact in terms of time saved - and she remains the only person to wear one at a Games.

The science behind the suit has been used in outfits for speed skaters, cyclists and swimmers since, while sprinters have also benefitted from the technology with things such as arm sleeves that feature vortex generators.

But the full suit with a hood? Athletes do not seem interested.

"The power of culture is so massive," argued Harber, who suggested arm sleeves were more popular due to their usage among NBA players.

"I think that's the main reason it hasn't been adopted is it's just not the look that athletics has. It's not something that people wear. 

"I know that the benefit is real. I know it's something that is quantifiable. I believe it's something that is never going to go away and I think inevitably it's going to be around forever and I think athletes will always be thinking about it.

"Maybe we were just ahead of our time."

And the reason athletes will always be thinking about it is surely due to Cathy Freeman and are her indelible evening in Sydney on September 25, 2000.