Trunk Flexion The vast majority of our S&C work is (quite rightly) done in a ‘braced neutral’ position when under load. As a result athletes often resort to moving their lumbar spine as a single block. The problem is that sports skills often require a pelvis that is mobile and a lumbar spine which can move and adjust. Lumbar Flexion focuses on segmental mobility of the lumbar spine with a strong posterior tilt of the pelvis and most importantly developing the strength to control that mobility and coordination.