Have you always wanted a sick, insane, incredible upper body? Biceps of steel, sleek toned shoulders, a shredded upper back...well, here it is: Jillian Michael's Killer Arms & Back, the fourth installment in the Killer series. You are going to look and feel amazing in that tank top, bikini or spaghetti strap dress. Killer Arms & Back offers three amazingly effective workouts that progress in difficulty. Stick with each 30-minute workout for 10 days and then progress to the next level. Jillian offers modifications for every single move, so whether you're an advanced athlete, a beginner or an intermediate exerciser, you will get the absolute most out of this program.