I have noticed that while sitting in the Sukhasan posture(picture below) for a long time, my feet suddenly become all stiff and i am unable to move it. What I deduce from the experience is that it is static, though I fail to understand how it accumulated at my feet.Does anyone have an explanation for this?
I have no idea how "static" comes into this, do you mean static electricity? Why would that be related?
Anyway, what you are probably experiencing is simple numbness caused by your posture applying pressure to a nerve: