Ok, I mean this is the craiziest thing I have ever seen. Imagine putting your body through this, try standing up for that long. How heavy are their shoulders, and how much can your shoulder withstand swinging that many times over your head. Your wrist for holding a racquet that much, absorbing the hits each time. The crappy part, is when its over, they have to keep moving their body, or the will cramp up horribly.