Arnold Schwarzenegger Pushed Himself A Little Too Far While Filming Commando

It's no secret that Arnold Schwarzenegger is a big guy ... and that's a bit of an understatement. Known for his impressive physique, he was a four-time Mr. Universe winner before becoming a movie star and taking on the role of Colonel John Matrix in "Commando."

Now one of his defining films, 1985's "Commando" laid the groundwork for his big-screen persona.

Retired Special Forces commando John Matrix is brought back into the line of fire when all of his former squadmates are killed by a gang of unknown mercenaries. The group, including one of his former men, Bennett (Vernon Wells) assaults his home, kidnaps his daughter, and tries to force him into carrying out a political assassination. But he's got other ideas.

The no-holds-barred action that follows sees Schwarzenegger dismantle his assailants one by one, chasing their leader to his villa in an attempt to rescue his daughter. It's a thrilling spectacle of stunts and shootouts and it's one of Schwarzenegger's craziest action films by far. But one thing that stands out, even decades later, is Schwarzenegger's physique.

A bodybuilder at the top of his game, the actor was in peak physical condition ... and he knew that his fans would tell the difference if he used a stunt double. "He never believed that a stunt person could have a body like his, and then his fans would know it wasn't his body," director Mark Lester told Yahoo.

Schwarzenegger pushed himself harder than ever before. But he may have gone a bit too far.

Filming began on "Commando" in April 1985, just six months after Schwarzenegger's career-defining role in "The Terminator." It clearly influenced director Mark Lester, too, who saw him on screen as the relentless T-800 and felt that his new lead could do anything.

"I think I was becoming delusional that he actually was that strong," said Lester.

He was determined to showcase Schwarzenegger as a real-life superhero — a commando capable of doing just about anything. And with his star at the peak of human condition, it's easy to see why he might think Schwarzenegger really was capable of it. It's not surprising that Colonel John Matrix dons a tactical vest for much of the film. After all, it allowed Lester to showcase every bulge of Schwarzenegger's impressive biceps ... and that's a surefire way to convince the audience that Matrix is the real deal.

The 45-day film shoot would turn out to be one of Schwarzenegger's most grueling. His director was adamant that he could do in real-life all the things that John Matrix was supposed to do onscreen. That included picking up a 200 pound phone booth and dangling a guy off a cliff with one hand.

But Schwarzenegger had to keep reminding him that he was only human.

As far as action films go, "Commando" is packed full of moments that highlight John Matrix's strength. At various points, we see Schwarzenegger rip a car seat out with his bare hands, swing from a chandelier like Tarzan, and impale several mercenaries with household objects.

But one of the most impressive moments is the phone booth scene. After tracking down one of the mercenaries, Sully (David Patrick Kelly), Matrix finds him alone, making a call in a mall phone booth. Rather than open the door and drag him out, Matrix violently shakes the booth, smashing the glass before ripping it out of the floor with his bare hands and tossing it across the mall.

Lester recalled that he kept telling Schwarzenegger:

"'Arnold, just lift up that phone booth. It weighs 200 pounds and you're lifting 350-pound weights.' And he said, 'Are you crazy? I can't lift that phone booth with a man in it!'"

Eventually, Lester conceded that Schwarzenegger was not, in fact, superhuman, and had production designers build a balsa wood phone booth that was much lighter and could be more easily picked up and thrown.

When he later catches up with Sully, Matrix grabs hold of him by the leg and dangles him over the edge of a cliff — a scene that Lester still thought Schwarzenegger could do unaided. Eventually, a stuntman held up by a harness was used to accomplish the shot.

"I thought he was the Terminator, and he kept having to say no," explained Lester.

Keen to live up to his director's expectations, even Schwarzenegger himself went a little too far.

Ever the perfectionist, Schwarzenegger performed many of his own stunts on "Commando." His reasoning was simple — the fans would know it wasn't him if he used a stunt double. Unfortunately, that led to a couple of accidents. During the film's big climax, John Matrix finally goes toe-to-toe with the big bad, his former comrade, Captain Bennet (Vernon Wells). The fight that ensues is brutal and bloody ... and resulted in Schwarzenegger damaging his shoulder.

"The mano-a-mano fight between Arnold and I was brutal," said Wells. "People were waiting to see which of us went to hospital first. He chipped a bone in his shoulder, I dislocated my elbow."

That's not all, of course. Schwarzenegger was keen to personally perform a close-up where Matrix is practicing with knives. After all, the fans would notice if it wasn't his ripped torso in the shot.

"There's this scene where Matrix is testing knives, and I wanted to use one of the bodybuilding doubles to do that because we were just seeing his hand," Lester said. "But Arnold said, 'No, you see part of my stomach! It has to be me!' And that's when he got hurt — the knife went right into his hand. We lost five hours while he went to the emergency room and had stitches. He never wanted to listen and do every possible thing, because his body was so awesome. You couldn't get anyone else to look like that."

It may have cost Schwarzenegger a chipped bone and stitches in his hand, but the result is a classic action flick that stands the test of time. Sure, it's got a ton of cheesy lines and some of the least-realistic action scenes on film, but that's why it's a stone-cold classic. And it laid the groundwork for Schwarzenegger's impressive action movie career to come.