Dolph Lundgren: Masters of the Universe was the first film I saw Dolph in, and then Rocky 4 as the villain. I've seen only a little of The Punisher, but he's one of the better action heroes from that era. And also Showdown in Little Tokyo with Brandon Lee. 

Sylvester Stallone: A brilliant action hero. Not at the top of the list, but definitely rivals most from that era. Most films he starred in during the 90's were outstanding. I enjoyed the Rocky films but have to say Demolition Man was by far his best film in my opinion, and the underrated Judge Dredd film.

Steven Seagal: Not in any of the Expendables films but definitely a great action star/martial artist. My favorite film would be the first Under Siege.

Jean-Claude Van Damme: One of my favorite action heroes is Van Damme, or the Muscles From Brussels. His standard improved a lot after Bloodsport and Kickboxer, although both were very good. Universal Soldier was his first big hit and his films became much more financially successful over time. A shame his career went down hill and he didn't get to play Gambit in any of the X-Men films.

Arnold Schwarzenegger: The greatest action star in my opinion is Arnold Schwarzenegger. His films were almost always excellent, or at least above par. Conan the Barbarian was his first really big film and became very successful. And of course the Terminator was one of his best roles. A lot of his 80's films were very good, especially Predator, although Raw Deal and Commando were a bit iffy. His 90's films were outstanding with T2 and True Lies. May have been great if he stayed an actor during his 50's rather than running for governor because I still feel he had a few decent films left in him like King Conan and possibly more Terminator films (something he has returned to).