Why is “pelvic stabilization” particularly effective in strengthening the lower back?
Stabilizing the pelvis eliminates the use of the hamstrings and gluteals. This creates an exercise which specifically focuses on just the lumbar extensor muscles. Since they have to do all the work, they derive all the benefit and respond by dramatically increasing in strength. (“Pelvic Stabilization During Resistance Training…” Archives of Physical Medicine and Rehabilitation.