When should action stars quit?

'The Expendables 2' reunites some of Hollywood's biggest action stars with Sylvester Stallone, Arnold Schwarzenegger, Jean-Claude Van Damme and Chuck Norris all returning to the big screen.

With an average age of 53 (including 'youngster' Statham) we wondered how much longer they could keep going. Who better to ask than Arnie, Jean-Claude Van Damme and Dolph Lundgren themselves?

[Related gallery: 'The Expendables 2' stars - then and now]

Watch the full interview below:

54-year-old Dolph Lundgren explained that he used to think that he'd stop at 60, but having seen Sylvester Stallone (65) and Clint Eastwood (83), he feels like he can keep going.

He said: "I still feel I can do a lot of the stunts, I can do the fighting, physically I feel pretty good. So long as I feel good and I'm hungry and feel I can do things with the character I want to keep going.

"Hopefully not forever, hopefully not until I'm 83 but you never know!"

Jean-Claude Van Damme, famed for his leg splitting trick claimed that you could play an action hero forever but that it "depends on the metabolism and the body and the person."

He went on to say that the type of training is key and his technique of changing his training has helped in stay in shape.

After a stint as the Governor of California, Arnie seems to have no intention of slowing down. Having told Yahoo! Movies that he thoroughly enjoyed making his first movie post-politics he joked that he might be doing action movies forever.

The 65-year-old said, "Maybe when I'm 100-years-old I'll still be running around on screen and creating action".

We hope so.

Watch the trailer for 'The Expendables 2'

The '80s action stars are reunited once again in 'The Expendables 2' when Mr. Church (Bruce Willis) enlists them to take on a seemingly simple job. When things go wrong, the team are forced to seek revenge in hostile territory, where the odds are stacked against them.

'The Expendables 2' is in cinemas now.