This script converts poly objects to ACT cgMuscles.
open and eveluate the script then assign a shortcut i did mine under the UI quad menu under all the other converttopoly etc etc.
then create a cylinder and select it right click and ConvertToActMuscle.
It is best to model your muscles form spheres or cylinder and the convert them.
you need ACT muscle plugin to run this script you can get this at www.turbosquid.com