• Support involves holding your breath. This is achieved by:
-keeping the diaphragm low
-keeping the ribs extended
-the interaction of three muscle groups:
1) Drawing the abdomen in around the navel, which pulls the pelvis upwards towards the body, straightening the back (using the abdominal muscles: the rectus abdominis, the internal/external obliques, and the transverse abdominis).
2) Contraction of the back muscles, which hold the ribs in an extended position at the back (using the latissimus dorsi).
3) Activation of the lumbar muscles, which attempt to tilt the pelvis forwards, trying to arch the back (using the quadratus lumborum).
• There is a struggle between the lumbar muscles, which try to arch the back, and the abdominal muscles, which try to straighten the back.
• The interaction between these three muscle groups should take the form of a steady, gradual, continuous movement, as if you were working against resistance.