It is true that the action of the TA
depends heavily on a co-contraction of our multifidi,
pelvic floor, and many other accessory muscles (inner thighs and hip external rotators) to truly offer stability, but this co-contraction is extremely important to the
health of our spine.
The smooth functioning of the
pelvic floor muscles
depends on the
health of all of the surrounding muscles and tissues, particularly those of the gluteals, i.e. your butt.