Sitting IN a hot bath–When one stands or sits or moves in meditation, the sensation, the very first hint of the presence of qi is a feeling…in the fingertips. “Your qi is flowing.”
Western science says this sensation is the direct result of extended study. One of the foundations of internal martial arts is relaxation–Song (See “Everybody Wants Peng” http://seattlesilverdragon.wordpress.com/2008/09/26/everyone-wants-peng/). When, through diligent practice, the proper amount of relaxation is achieved, a sensation is detected. Tingling or perhaps warmth is felt in the fingertips. This means the very smallest capillaries in the fingers are opening up, perhaps for the first time of years, and blood is filling them.
This is qi. Sublime relaxation.
When one steps into an excrutiatingly hot bath, a similar phenomenon occurs. But this is a sort of capillary rape. The hot water rips them open and blood rushes in. The sensation is a mixture of pain and pleasure and a mild sadness follows once the capillaries have achieved their maximum dialation.
What is qi? There are many answers and probably most of them are right. But be aware the next time you bathe.