Was the supposed action in The Running Man filmed live or not?

It was the premise of the in-movie show that the "winners" would receive pardons...

 Now Ben Richards could have gone to prison and paid the penalty but 
 instead he volunteered for The Running Man...and have a chance at our 
 fabulous przses like a trial by jury, suspended sentence, maybe even a 
 full pardon like our previous winners, Wittman, Price and Hadad. You 
 remember them, Wittman, Price and Hadad, there they are, and at this 
 very moment they're basking in the beautiful Maui sun, their debt to 
 society paid in full.

^Source

...but in reality they were killed (presumably by Fireball) and their escapes faked.

Recall that Ben and Amber were replaced by digital body doubles and "killed" for the audience even though they had escpaed.

The point is that the show is a sham. There is no actual escape, the totalitatian state which runs the show wouldn't allow it.

Recall the exchange after Ben & Amber's "deaths"..

Amber
 What's wrong? You should be happy, we're officially dead. We can go 
 anywhere, do anything. 

Ben
  No, don't you understand it. He'll never let us out of here alive, they 
  can't afford it. They'll get the police, the army and hunt us down like 
  dogs, off camera of course. 

So, yes it was filmed "live" until it was inconvenient for the state and then what was happening was either not shown or a complete fake.