One of the most important functional roles of the hip abductors takes place during the single-limb support phase of walking to maintain frontal-plane stability.
Just about every sport requires athletes to laterally walk or run with abduction. In real-life circumstances, we also have to move laterally in situations such as moving around people in a crowded mall or on sidewalks. This action requires stability as well as balance and awareness.
Weakness or poor timing issues (motor control) in the gluteus medius region can reduce athletic performance and serve as a catalyst for lower-body injuries and changes in gait. There are a number of factors that contribute to gluteus medius weakness. Lifestyle factors contributing to gluteus medius weakness include sleeping on your side (predominantly the same side), and flexing and adducting your top leg over your bottom leg. In addition, standing predominantly with all of your body weight on one leg can cause the pelvis to move sideways and the hip joint to adduct; this can contribute to weakening of the hip abductor muscles.
Iliotibial band (ITB) syndrome may result from gluteus medius weakness. The lack of control during thigh abduction and external rotation places greater tension on the tensor fascia lata and ITB.1 Gluteus medius dysfunction can also contribute to patellofemoral pain syndrome (PFPS), resulting in decreased hip control and increased femoral adduction and internal rotation.2