text: Throwing in general is done with your legs, with that energy transferred through your trunk to your shoulders and arms.\n\nI'm sure you're already on a total workout program, but don't skimp on the abdominals work.  If your abs aren't strong, the energy generated by your legs can be lost there.\n\nAlso, throw a LOT.  That's really the only way to get increases in velocity.  I played baseball over the summer and that was really the only throwing I did.  Then in 10th grade, I played football (QB) and baseball (Catcher).  By the time I graduated, I was throwing over 80mph, just in those three years because I threw so much.