Check out this leg workout exercise, called the "hang-clean to front-squat to push-press". This exercise from Men's Health is a combination of three great compound exercises, so you can imagine, most muscles in your body will be working on this one -- an all-over body workout.
Grab a bar-bell with a shoulder-width grip and dip your knees as if you were about to jump. Quickly reverse the motion and shrug your shoulders as you pull the bar straight up and rise onto your toes. As the bar approaches chest height, bend your knees and swing your elbows forward to catch the bar in the crooks of your fingers.
Now, lower your body as deep as you can comfortably go. Push back up to a standing position then press the bar overhead. Lower the bar to the standing position. That's just one rep.
This exercise is a combination of three great compound exercises, so as you can imagine, most muscles in your body will be working at some point during the execution of this lift. It is vital that you do not hold your breath during any stage of this exercise. Exhale out when you push and inhale as you recoil.