Within the Australian swim team, they call him “the Professor”. In part, it is because Cameron McEvoy graduated with a science degree, majoring in physics and mathematics. It’s also because, in contrast to some team-mates, he is more than happy to hold court with journalists and give lectures. “I can stand here for a very long time,” he laughed on Friday night. And finally, because McEvoy has used data and sports science to quietly revolutionise the one-lap “splash and dash” 50m metre freestyle.

On the third-last day of swimming action at the Paris Olympics, McEvoy’s doctorate was awarded. At his fourth Games, after more than 12 years of heartbreak, the 30-year-old walked to the starting blocks for his only event this week. Sub-22 seconds to make or break an Olympic campaign. McEvoy walked to the blocks, slammed his hands down and soaked in the atmosphere. An entire career to be defined by the moments that followed.

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The stadium was going wild, whipped into a frenzy by local favourite Florent Manaudou. “I took the first stroke and the crowd was effectively the same noise level as when I was on the block,” McEvoy said. The Australian quickly hit his rhythm, before charging for the wall. “Under the flags it was just hope that I could line this touch up, lean in and get my hand on the wall first,” he added.

For the first time in his long Olympic career, McEvoy did touch first. After the heart-break of London 2012, where a favoured Australian relay team finished fourth. After the disappointment of Rio 2016, where McEvoy entered with an Australian record in the 100m freestyle only to be upstaged by team-mate Kyle Chalmers. And after the distress of Tokyo, another sub-par Games which prompted McEvoy to momentarily quit the sport.

At long last, separated from the silver medallist by just five one-hundredths of a second, McEvoy was king. “It’s ultimately incredible,” he reflected afterwards, the professor momentarily lost for words. “The journey of a lifetime.”

It almost never happened. Following Tokyo, McEvoy took an extended break from swimming – almost a year out of the pool. He contemplated his options. Ultimately, the Queenslander decided he would return to the sport – but only with a radical new training program.

McEvoy wanted to focus on strength and resistance training, prioritising sprint-specific work rather than just clocking up the kilometres. With his coach Tim Lane, and specialists at the Queensland Academy of Sport, McEvoy carefully analysed every aspect of his stroke and technique – often swimming in a 25m pool with specialised equipment. McEvoy was working smarter, not harder (in one social media post, McEvoy is standing in a pool pointing at a laptop, with the caption: “In the lab”).

“I started off with the perspective that it would give me closure,” he said. “I always knew that there was potentially another way to do things for sprint freestyle. I’ll do it, if it didn’t work, the closure is – right, there wasn’t, and that’s just where I was in my career, that was the potential I could live up to. If it worked, then I could see how far I could get. “It was a win-win situation,” he added.

There was a moment, in May 2022, when McEvoy made up his mind. After winning gold on Friday, he pinpointed a photo on his Instagram feed from two years ago, taken on a day he and his partner had spent in Paris following a family wedding in France. Wearing a t-shirt from the Tokyo Games, McEvoy faces away from the camera towards the Arc de Triomphe. He gave the photo a one-word caption: “Reconnaissance.”

“It was on that day when the photo was taken where I was like, ‘alright, I’d love to be here, I’d love to give it a crack, I don’t know how it’s gonna look,’” he said. “That was the day I went all in.” On Friday night, the gamble paid off in spades.

Having triumphed in Paris, the baby-faced assassin – elder statesman of the Dolphins team (at 30 its oldest member) – says he is not going anywhere. At the Olympic swim trials in June, McEvoy joked that he wanted to swim until the home Games in Brisbane in eight years’ time. It turns out he was serious.

“If the motivation is there, if the body is holding up, I don’t see why not,” he said. “A home Games would be absolutely unreal. I’ll be 38, and there have been older swimmers who have won world championships. We’ll see what time has for me.”

McEvoy has made no secrets about his new training regimen; he said he has been contacted by many athletes who have followed in the footsteps of his new swimming-lite model.

“We’ve been inundated with questions and interest,” he said. “I think we’ll go a long way, not only for the athletes who are up on the upper echelon of high performance, but the amount of ex-swimmers who quit when they were 16 or 17, because they just didn’t like the kilometres, or they had injuries and everything.”

The sprinter says he now hears from swimmers who have returned to the sport after adopting the sprint-specific approach, falling in love with swimming all over again. McEvoy has hinted he will reveal more specific details about his gold medal-winning training approach in the months ahead.

Not long after his 50m triumph, McEvoy mentioned that, in the weeks before the Games, he had posted a video of him training with a specialised resistance weight-belt – highlighting a particular aspect of the direction of the resistance which he considered novel. “There’s many more,” he chuckled. “We’ll need a few lectures to go over it.”

This professor’s class has just begun.