Full Squat | Anatomical Analysis Lumbar flexion in the deep squat stage because of mobility limitations in the hip joints and pelvis. It's important to maintain the natural curves in your spine to prevent lower back strain. In full squat, freedom of movement and good mobility in the hip joints and pelvis are essential for maintaining neutral spinal curves. Perform the squat up to the stage in which we cannot maintain the lumbar curve. In other words adapt the full squat to the exerciser's needs.