Comedian Jack Black has vowed never to play the part of an action hero - because he doesn't have the musclebound body of Arnold Schwarzenegger. The Shallow Hal funnyman admits he plans to stick with comedy roles, as he isn't suited to more physically demanding parts - and insists other actors should know their limits. He says, "I mean I love action films, and it would be fun to do one, but no one's going to buy me as the action hero. Nobody wants to see me rising out of smoke naked like Arnold Schwarzenegger in The Terminator.....or do they? "No, you've got to know what you are, what people see you as, what your strengths are and what you can pull off. I think an important part of being an actor is having a sense of self-awareness. "You see it a lot where people think they're this or that and they're just awful."