The SLAB - A Quick Diagnostic Tool
The SLAB, or Single Leg Alternating Bridge, is a great movement that can be utilized as a "quick and dirty" screen. It provides valuable information about the athletes current movement patterns, stability inefficiencies, and desired methods of compensation. Although it doesn't show all, it can be beneficially used to aid in determining the proper progressions or regressions needed to improve overall performance. Below are three quick tips that are discussed in the video to appropriately execute the SLAB as a screen.
1. Sagittal Plane: The FIRST plane of motion that needs to be established and perfected. Without this plane, we are setting our athletes up for failure. During the SLAB, the pelvis and low back will help you gauge the degree of sagittal plane competency. An anteriorly tilted pelvis (forward displacement) that results in an increase in lumbar lordosis (back extension) demonstrates an inability to properly stabilize or understand the sagittal plane.
2. Frontal Plane: The next plane of motion to train once the sagittal has been mastered. Appropriately demonstrating the frontal plane directly correlates with the ability to maintain a neutral pelvis and low back (sagittal plane). The most common compensation would present itself has a lateral (side-to-side) motion of the hip. This can be used as a means of generating momentum in the hopes of accomplishing full hip extension. Additionally, you will most likely see an increase or collapse of the arch from the foot making contact with the ground.
3. Transverse Plane: The most desired, yet most challenging plane of motion to achieve. The transverse plane comes with the perquisite of comprehension and proficiency of movement execution of the sagittal and frontal plane. The main compensation here will present itself as a rotary component during hip extension. As a side note, during normal gait, stance phase will have a rotation component. This helps us absorb force as well as generate force in preparation for swing phase. However, there is a difference from compensatory rotation versus acceptable rotation. The former will present as an aggressive and disturbed whipping motion that will be obvious to the observer. The latter will create a mechanical advantage for the hip musculature to optimally stabilize the pelvis.