We know what actors and actresses go through to become superheroes. So we can assume that it takes just as much physical and mental training to become a gladiator.

Even though Gladiator premiered 20 years ago now, Russell Crowe still had to go through what the likes of Chris Hemsworth, Chris Evans, and the rest of the cast in the MCU had to endure to get in fighting shape and literally transform into superheroes. But none of them earned an Oscar for their efforts, like Crowe.

But before he started his gladiator training, Crowe's first task was to lose 40 pounds. He wasn't going as far as some actors and actresses go to lose or gain weight for their roles, but it was challenging for him.

Here's what he had to do to transform into Maximus.

This Wasn't The First Time He Lost Or Gained Weight For A Role

There's no doubt that Crowe had to be as slim and fit as possible for his roles in films like L.A. Confidential (1997), where he played a cop, and Mystery, Alaska (1999), where he played a small-town hockey player.

But his slim physique had to quickly go within the year for his role as the former tobacco executive Jeffrey Wigand in The Insider. Crowe didn't really have to bulk out for the film, but he did have to weigh more than a strong gladiator.

Related: Russell Crowe's 'Gladiator 2' Was Going To Be Completely Crazy

He gained 50 pounds for Wigand but had to lose it all for Maximus the year after. The way he accomplished his weight loss was close to what actors who are trying to become Superman do. And in fact, Maximus was a sort of Superman for the Romans.

Soon he was experiencing an extremely strict diet and training regimen.

His diet consisted of six to eight meals of lean protein, complex carbs, and healthy fats, daily, to keep his metabolism fired up. According to Men's Journal, Crowe chose to eat high-fiber fruits and vegetables to help control his appetite and "aimed for one gram of protein per pound of his body weight to maximize muscle gain."

Training-wise, Crowe used weights to gain muscle and had to learn how to use a sword, as that was his character's biggest strength. He did all this in the comfort of his farm in Australia.

Related: Russel Crowe Says 'Gladiator' Script Was So Bad Producers Didn't Want To Send It To Him

But even though he did reach his goal and became such a believable gladiator, that didn't mean that the role didn't take something out of Crowe. There were a couple of on-set accidents, and Crowe sustained a lot of injuries. He broke bones in his foot and hip, he had to get stitches on his face, and he lost feeling in his right forefinger because a sword sliced into it.

"I injured myself a lot on Gladiator," Crowe said in an interview. That's putting it lightly.

Russell Crowe Doesn't Like Talking About His Preparations But Might Be Losing Weight Again For 'Gladiator 2'

Crowe was once again brought to fighting shape for Cinderella Man in 2005, American Gangster in 2007, Robin Hood in 2010, Les Misérables in 2012, Noah in 2014, and, of course, he had to be fit to play Jor-El, Superman's father in Man of Steel.

But three of his most recent roles required him to gain weight. According to Us Weekly, Crowe packed on the weight for the film The Nice Guys in 2016 and then had a dramatic weight loss.

"I was [268 pounds] the first week of August last year," he explained on Australia’s Fitzy & Wippa radio show. "I did a movie called 'The Nice Guys,' so I wanted to be the physical juxtaposition of Ryan Gosling."

"I’m clawing my way back from that, so I’m about [216 pounds] at the moment," he said. But he didn't stay that weight forever, he had to gain weight again in 2018.

Not to be outdone by Christian Bale, who packed on a ton of weight to play ex-Vice President, Dick Cheney, for Vice, Crowe followed suit for Boy Erased. That was followed by the mini-series The Loudest Voice, where he played Roger Ailes, in 2019. Going from one to the other probably wasn't as hard as going from The Insider to Gladiator.

Related: 15 Behind The Scenes Secrets About The Making Of Gladiator

But just because he seems to be just as good as any actor or actress when it comes to gaining or losing weight for roles, doesn't mean he wants to talk about it.

"I’ve really stopped talking to people about preparation," he told Entertainment Weekly when asked about his weight gain for The Loudest Voice. "Because preparation becomes the article. It becomes what people talk about. And that’s really boring. The mathematics of how you get there is nowhere near as much fun as what you did when you got there."

Once again, his weight loss is being talked about, however. With the news of Gladiator 2 circulating, some publications have begun to spin rumors that Crowe "desperately" wants to lose 150 pounds off his "supposedly '350-pound' frame" so he can reprise his role in the sequel.

This rumor has been squashed, however, because of one minor detail in the first Gladiator. Crowe's Maximus dies at the end, so how will he come back from the dead? Just because we're now used to our favorite characters coming back from the dead (Vision in WandaVision) doesn't mean Maximus can come back. Crowe's own version of Gladiator 2 did include time travel after all.

The plot of Gladiator 2 is reportedly going to center around Lucius, Lucilla's son. But the film is still in its early stages. Maybe Crowe will reprise his role as a ghost, in an old Luke Skywalker-like fashion that Hamill eventually did in Star Wars. Either way, we know Crowe will be able to lose the weight he wants if he is reviving Maximus.

Next: Who Are Russell Crowe's Kids?