Would side bridging be good for the SIJ to prevent pain in gait? [news]
Side bridging particularly strengthens the quadratus lumborum (QL) and tensor fascia latae (TFL) as the major mobiliser muscle groups. When you take weight through your leg you need a pelvis that can transfer the load from your leg to your trunk efficiently. In the stance phase of gait, therefore, your SIJ on the weight bearing side must be in a stable, "close pack" position (see the diagram below). And when you swing your leg in the swing phase there needs to be some give in the pelvis to allow movement to occur, called the loose pack position in the SIJ. The close pack position for the SIJ is a posteriorly rotated ilium bone against a "nodded forward" or nutated sacrum.