Which muscle group is located just below the glutes and pulls the upper leg backward?

The hamstrings are the muscle group situated just below the glutes and are primarily responsible for pulling the upper leg backward. This group consists of three muscles: the semitendinosus, semimembranosus, and biceps femoris. They play a critical role in movements such as running, jumping, and cycling by facilitating knee flexion and hip extension. When these muscles contract, they pull the femur (thigh bone) upwards and backward, which is essential for activities that require powerful leg movement.

In contrast, the quadriceps, located at the front of the thigh, are responsible for extending the knee and do not aid in pulling the leg backward. The latissimus dorsi is a large muscle of the back that primarily functions in shoulder movement rather than leg movement. The obliques are muscles situated on the sides of the abdomen that assist in trunk rotation and lateral flexion, with no direct involvement in movement of the upper leg. Therefore, recognizing the specialized function and location of the hamstrings clarifies why this muscle group is indeed responsible for the action described in the question.