Final answer:
Activating the hips' external rotators and abductors results in increased knee stability by maintaining proper leg alignment and supporting the patella's tracking over the knee.
Step-by-step explanation:
The benefit of activating the hips' external rotators and abductors is A) Increased knee stability.
The hip joint's external rotators and abductors play a crucial role in stabilizing the lower limb. When these muscles are strong and engaged, they help maintain a proper alignment of the leg, which is vital for knee stability. The external rotators, including the gluteal group, help to twist the thigh outward, while abductors are responsible for moving the limb away from the body's midline, both of which are essential movements that contribute to stabilizing the pelvis and knee.
The gluteal group, specifically, is known for raising the knee at the hip, as in a marching action, which supports not only the lateral rotation but also the abduction of the thigh. During knee extension, such as when straightening the leg, the quadriceps muscle exerts a pulling force that includes a lateral component; having strong hip muscles helps ensure the patella tracks correctly over the knee, thereby increasing stability. Furthermore, the iliotibial track, which is connected to the knee, relies on these muscles for support, further contributing to knee stability.