It's depends of situations, sometimes you should be aggressive, but sometimes you should play bet, and sometimes you can play check.It's depends of situations man.
I'm not a big fan of A K. Preflop even 2 2 is in the lead. If you don't catch but still continue to bed you are just giving more chips to your opponent! If I have A K and catch nothing on the flop I fold to the first bet unless the blinds are very low and they just make the minimum bet!!!