The "gluteus maximus" is the strongest muscle in the body and covers a large part of the buttock. It connects the ilium, sacrum, and coccyx to the femur by tissues of the thigh and acts to extend the thigh. The gluteus maximus causes the leg to straighten at the hip when a person walks, runs, or climbs. It is also used to raise the body from a sitting position. The "gluteus medius" is partly covered by the gluteus maximus. Its fibers extend from the ilium to the femur, and they function to move the thigh out and rotate it medially. The "gluteus minimus" lies beneath the gluteus medius and is its companion in attachments and functions. The "tensor fasciae latae" connects the ilium to the tissues of the thigh, which continues downward to the tibia (bone in the lower leg). This muscle functions to abduct and flex the thigh and to rotate it.