Spreading of the back

We have been talking about how when doing the transverse couple there should be a feeling of spreading in the back. I've been having trouble feeling that sensation and I've felt that when learning the foot couple and the transverse couple in the waist it helps to be able to mentally visualize or have some idea about what is causing the sensations to occur. For the foot couple and transverse couple it makes sense to me when I think about the tensegrity model that gravity is pushing down on my body which causes the bones to be pushing outwards and then the connective tissue feeling stretched because it's holding things together. When I think about the back spreading though it doesn't make as much sense to me but I was looking at pictures online and I found this. Does this seem like a good visualization about what is happening inside the body that is causing the spreading in the back? When gravity is pushing down it's causing the bones in the pelvic to go outwards and the connective tissue is holding it together but some of the fascia wraps around from the front of the ribs and goes along the back? 

 

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