I spent quite a bit of time at GAIN 09 examining the currently accepted model of core stability. ALL of the big core guys use it. It appears in Andry Vleeming's books from the late 90s.
It is the "pirate ship" concept. That is, a ship mast (spine) with a skull on top (head), with 2 sets of guy wires attached. An "inner unit" (multifidus, TA, Ext. Oblique et al), and an "outer unit" (erector spinae, rectus ab. et al). The inner unit providing inter segmental stability, with the outer unit in control of column movement in general.
My question was, what would happen if you took this model and tossed it in the air (gymnastics, platform diving etc)?...or tossed it in a swimming pool upside down or on it's side (swimming)? Is not core stability required in these environments?
I believe the problem is spine stability is interchangeably used with core stability. That's where we get the concept of the core as a "rigid pillar". Core strength expressed as "stiffness", connotating something isometric in nature. It's very rare someone injures their spine lying down, so this makes sense.
But when we think of core, we're not only thinking the external's influence on the internal, we are also thinking vise versa. That is, the role of the core in ACL prevention, or hustling up off the ground after a fall. I've seen McGill's bracing exercises used in ACL prevention programs. Is this the proper application of a bracing exercise?
Juan & other physios & A.T.'s that treat backs, I would really enjoy your input on this. Did Vleeming intend this to be a core stability model?