Sound Hip Function definition.

• A. The athlete's ability to rotate the hip only.
• B. The athlete's ability to straighten the elbow.
• C. The athlete's ability to flex and extend the hip to maximize its contribution to movement.
• D. The athlete's ability to abduct the shoulder.

Answer: (C)

The main concept being tested is how the hip contributes to movement through its primary actions. A sound hip function means the hip can move through its key movements, specifically flexion and extension, and use them effectively to contribute to overall movement.

Being able to flex the hip allows the thigh to move toward the torso, which is important for positions like the preparatory phase of a squat or the swing leg during running. Being able to extend the hip enables a strong drive to push the body upward and forward, powering hip extension in jumps, climbs, and lifting tasks. When both actions are available and coordinated, the hip can contribute maximally to most athletic movements.

The other options focus on movements of other joints (elbow or shoulder) or describe a limited action (rotation only) that does not capture the hip’s overall ability to participate in movement. Therefore, emphasizing both hip flexion and extension to maximize movement contribution best defines sound hip function.