Theory: Can power cables induce AC voltage in human body?
I would forget the pooling theory and model with normal circuit elements. You are mixing static electricity models with discrete circuit models.
With shoes, R4 is nearly infinite.
Barefoot, R4 is smaller, how much depends on the floor type. C2 is larger. Either of these will cause the voltage divider to reduce the voltage on the right hand. It is difficult to determine which is the primary effect.
If you repeated the experiment barefoot standing on a thin layer of mylar you could learn more.
Note that internally, bodies conduct electricity much better than your skin resistance.



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