I'd say you're missing out with the movie. It's so insanely detached from what's in the book you won't even care after the first few minutes, really. Even the rules of the Running Man game are fundamentally deformed to the point where you have to ask, why even bother with an "adaptation"? That being said, it really IS a classic early Arnie film, definitely one of the more entertaining ones. Less depressing dystopia with mothers giving cocaine to their dying toddlers so they wouldn't cry, more one-liners and 80s action heroes.

In addition, if you got a paperback edition in the 2000s in Hungary, which is what I ended up with, the front cover was clearly a close-up picture of Sylvester Stallone. I kind of appreciate that sort of subtle piss-taking.