Muscles of the hip the ilium. Together these muscles are commonly referred to as the "iliopsoas". This group consists of the externus and internus obturators, the piriformis, the superior and inferior gemelli, and the quadratus femoris. These six originate at or below the acetabulum of the ilium and insert on or near the greater trochanter of the femur. Additional muscles, such as the rectus femoris and the sartorius, can cause some movement in the hip joint. However these muscles primarily move the knee, and not generally classified as muscles of the hip. The hamstring muscles, which originate mostly from the ischial tuberosity inserting on
Leg raise in this movement by using the lats and other muscles to perform shoulder extension. The demands of force on the muscles can be increased through altered posture or apparatus. Extending the knee joint (often called a straight leg raise) increases the demands of leverage on both hip and spine flexors. It also allows the rectus femoris muscle to contribute, for both the supine straight leg raise and the hanging straight leg raise versions, although the muscle will be in active insufficiency in the latter case. The generic term "leg raise" usually indicates a bended knee, though the term "knee raise"