The genius of Chinese medical theory lies in the fact that it connects everything into a comprehensible whole, allowing practitioners to see the Big Picture. That allows us to relieve symptoms, break up chronic syndromes, and discover and fix ultimate causes.
Economic and cultural imperatives over the last three decades have shoved many people into lives filled with hurrying and worrying. Both of these habits create excess yang in the form of heat rising into the upper body. As the heat rises, it creates turbulence, which we call internal wind. Wind can be defined as uncontrolled and purposeless movement or its corollary, absolute stillness, similar to atmospheric wind or stillness. The energy most affected is your Chinese liver (gan).
This liver wind is a nasty business, and can easily confuse and scatter the qi and blood of the upper body and the head, causing shaking, dizziness, and fainting. Qi is that substance which animates everything in the body, and when the qi is scattered and confused, the body has trouble moving, resulting in a weak feeling. The sudden rising of energy from the middle abdomen where the liver resides will pull the qi of the stomach upwards also, accounting for the feelings of nausea.