The gluteal muscles are the set of muscles that comprise the buttocks. They include the gluteus maximus, the gluteus medius, and the gluteus minimus. The human body has two of each of these muscles, with one set occurring on the left side of the buttocks and the other on the right side. Working together, the gluteal muscles control many of the movements of the upper leg, including rotation of the thigh, and abduction and rotation of the hip.
Of the three gluteal muscles, the gluteus maximus is the largest and also the closest to the skin. Originating at the top of the pelvis and attaching across the upper portion of the femur, it is this thick, wide muscle that gives the buttocks their shape. The gluteus maximus performs several important functions in the thigh and pelvic areas. For instance, it assists in the extension of the thigh and the rotation of the hip joint as well as enabling the body to rise from a sitting position by pulling back the pelvis.
Next in descending order of size is the gluteus medius. Like the gluteus maximus, which partially covers it, this muscle is thick and begins at the upper pelvis. It occupies significantly less surface area than the larger muscle, however, and terminates at the greater trochanter, a backward-extending protrusion of the femur found just below the head of the bone. The gluteus medius is crucial to thigh support during walking and hip flexion — when humans walk, this muscle supports the weight of the body as it is placed on the thigh, thus keeping the pelvis from tipping away from the weight-bearing leg. Additionally, each time the hip is flexed or extended it assists in rotating the thigh.
Smallest among the gluteal muscles is the gluteus minimus. This muscle is located beneath the gluteus medius. It originates at the outer edge of the mid-pelvic region and concludes, like the gluteus medius, at the greater trochanter. Most of the functions of the gluteus minimus are performed in cooperation with the gluteus medius; it assists, for instance, in thigh rotation and the flexion of the hip.
Stress to the gluteal muscles caused by overly vigorous physical activity can lead to soreness in the area. There are a number of stretches that can help soothe gluteal pain and stiffness. Lying on the back and pulling the knees up to the chest one by one, for example, can ease discomfort in the gluteus maximus. The gluteus medius and gluteus minimus can be stretched by lying on the back, bending one knee, and crossing the bent leg over the opposite leg, using the hand to gently push the knee toward the floor.