numbness (but no pain) in our legs

A very common experience: we sit in a weird position and standing up we perceive in our leg numbness and lack of force... but no pain !
The weird sitting position has blocked a correct blood flow but in a short span of time the "surprise" is gone.
According Dr. Sarno the TMS pain is the result of a mild deficit of blood flow (I mean oxigen) generated by the autonomic nervous system in order to create distraction from unbearable and threatening emotions and feelings.

But.... is actually the mild restriction of blood flow the cause of the pain? How about our dayly experience with numbness in our legs?