thank god, some guys who listen to rap!
when your working out you want agry or violent music, and rap and hip hop tends to be about fighting or shooting. dont get me wrong, theres nothing wrong with rock, but its just not my thing

DMX - X gonna give it to ya/ up in here
jadakiss - times up
xibit - say my name/multiply
Nas - got yourself a gun
Eminem - square dance
slim thug - i aint hear of that
Dizee rascal - stand up tall/stop that
Mase - breath stretch shake

that sould keep you going. they got some good beats to them, and a fair few feature violence!

if you like rock: i dont really have to much knowlege on it...
Hblock z - i got the power
limp bizkit - break stuff

happy training