The hips are a common area of dysfunction for many people. They play a central role in activities of daily living, sports, and in fitness training. When the legs are not even or in a split stance, this dysfunction is even more evident. Common activities like walking, jogging, running, sprinting, jumping, and some types of lifting involve a split stance. The dysfunction in the hips can increase risk of injury in the spine, knees, and feet. Often, pain, weakness, instability, and decreased range of motion are evident in one of these areas when you have dysfunction in the hips.
While there can be many origins of dysfunction, such as an old injury and compensation, simply sitting causes a shift in hip function. Often, we see shortened hip flexors (front of hip), weak glutes and hamstrings (back of hip). This combination causes the pelvis to destabilize (rotate) at rest or with exertion. This is a common low back, knee, and hip pain in runners. The tilted (or tilting) pelvis can add to instability (bending) of the low back. Also, it can shift much more stress on the front leg during these split stance exercises.
During the correct repetitions (first three) my spine remains vertical, the hip flexors (of the back leg) lengthen, while the glutes contract strongly to maintain this motion. The opposite is true during the last three repetitions. The hip flexors (front of the hip) of the back leg contract strongly, pulling the torso forward. The glutes (on that same leg) don't contract strong enough to balance the pull of the hip flexors and keep the knee (of the back leg) behind the hip joint. As a result of this dysfunction, the front knee withstands more force and the spine flexes forward.
The Split Squat is a good exercise to gauge your hip function. Often, hip dysfunction causes movement inefficiency and compensation. This is a great assessment for runners, lifters, and everyone else who wants to move efficiently and stay healthy. Give it a shot and let me know how you do.