Arnold Schwarzenegger and Sylvester Stallone battled over the level of body fat and kill counts in their films.
The Predator actor, 76, and his former rival Sly, 77, warred over everything from their earnings to their muscles and the size of the weapons they wielded in their films at the peak of their action movie pomp in the 1980s.
In an upcoming joint TV interview titled TMZ Presents: Arnold and Sly: Rivals, Friends, Icons, the ageing muscle-bound Hollywood veterans admit they are still unsure who had the bigger career.
A preview of the chat shows Arnold sitting alongside Sly saying: "We ended up kind of like, 'Well, you killed 28 people in the movie; I killed 32'."
Sylvester added: "I got to top that."
Arnie later said: "He killed 80 people, so I had to kill 87 people."
Rambo and Rocky actor Sly added: "It was now the body count and then it was kind of, like, 'Well, what was your body fat?'"
"I was down to seven per cent."
Arnie added: "And then I said, 'I was down to 10 per cent.' So it became a competition with the body."
The Terminator star and former governor of California admitted he got jealous of the weapons Sylvester used on camera, from his Rambo knife to the sub-machine guns he wielded in the franchise — and admitted he soon demanded automatic guns that were just as huge.
Arnie went on: "And then he started using machine guns that were kind of, like, huge machine guns. I was running after him, he was not running after me."
"So I said, when we did Predator… I've got to have a bigger machine gun than Sly used in Rambo.
"So this is how it went."
Arnie and Sly have since become pals, enjoying a decades-long friendship since they were arch-rivals in the '80s.
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