For general information:
When you slap your thigh, or your girl-friend's butt, it pushes all the capillary blood out of the surface of your skin, making it turn white. The blood returns in an uneven manner that leaves the area looking patchy white and pink. It is the blood in the skin that makes us white people have a slightly pink color.
The easiest and least painful way to demonstrate this for yourself is to merely push in the pad at the end of your finger and you will see around the edges turns white. Lift the pushing finger and you will see the blood rush back to the finger pad. It happens quickly so be sure to stay sharp!
Dead people look white and pale because as soon as they die the blood follows gravity and flows to the lowest point. If they are sitting in a chair their legs will swell and turn bluish-purple like an ugly bruise. If they are laying in bed it will happen to their backside.
Like many of us have said for years here, chi is merely an explanation for phenomena that could not be explained because of the lack of proper scientific knowledge. Apparently the Shaolin monks do not learn any modern anatomy and physiology, so at least on this topic they appear a bit ignorant and/or naive.