Movement Science Midterm Practice Test

When moving through forward bending with multiple body segments, the hips, pelvis, and spine need to work together rather than letting the lumbar spine carry most of the load. If hip mobility is limited, the pelvis can’t rotate or tilt adequately to allow the hip joints to flex as needed. As a result, the lumbar spine ends up taking more of the motion to reach the same end range. This pattern—limited hip mobility that causes the lumbar to compensate during multi-segmental flexion—is a common lower-body dysfunction that shows up as excessive lumbar motion during MSF.

Think of it as a redistribution of effort: healthy MSF relies on the hips contributing to flexion, with the spine staying relatively neutral or moving only as needed. When the hips are stiff, the spine must bend more, which can lead to low-back strain over time. Addressing hip mobility and teaching a proper hip hinge helps move the demand away from the lumbar spine.

The other possibilities touch on related issues but don’t capture the most direct mechanism. Thoracic rigidity involves the upper back rather than a lower-body limitation. Hip flexor tightness can influence pelvic position and lumbar curvature, but the key driver for lumbar compensation during MSF is limited hip mobility itself. Ankle dorsiflexion restrictions affecting knee valgus relate more to leg alignment during squats or lunges than to the primary lumbar compensation pattern seen in MSF.