Uddiyana Bandha is often misunderstood as a simple contraction. By perceiving the updraft of the iliopsoas as a simple contraction, practitioners mistakenly tighten their gut. But Uddiyana Bandha involves the length (and width) of the entire iliolumbar region. This became clear to me in my study of Iyengar Yoga. Some time ago. B. K. S. Iyengar made the point that the essential movement of Uddiyana Bandha is accomplished in Urdhva Dhanurasana (Upward Bow Pose). In this backbend, the iliopsoas muscles and anterior lumbar spine are not contracted but fully lengthened. Iyengar’s point was that the length of the abdominal spine and adjoining psoas muscles is instrumental to the performance of the bandha.
To empty is to let go. Typically we hold onto so much stuff. We hold onto ideas, belief systems, family members. We hold onto ingrained ideas about ourselves like “I am not good enough and “there is nothing I can do to change.” To empty is to let go of the old—the old paradigm, the old attitude, the old self. By emptying we become more open, more available, more in the here and now.