Muscles of the Leg (Human)

The thigh muscles are often collectively called the quadriceps, which consist of four separate muscles:  rectus femoris, vastus lateralis, vastus medialis, and the vastus intermedius.  On most diagrams, the rectus femoris is shown as the front muscle that runs parallel to the femur.   The word “rectus” means straight, and generally is used to describe muscles that lie vertical to the body’s center.  For example, the rectus abdominus is the muscle that has parallel fibers that run up and down the abdominal region, an area commonly called the “six pack” in body builders.

For students attempting to learn the thigh muscles, identifying the rectus femoris is a good place to start.  The vastus medialis (E) and vastus lateralis (D) lie to either side of the rectus femoris (C) as shown on the image.  The sartorius (A) is the longest muscle in the body and it runs the length of the thigh from the hip to the inside of the knee, crossing over the rectus femoris.  On the lateral upper side of the leg is the tensor fasciae late (B) and with the gluteus maximus helps to stabilize the hip during extension.   The inside of the leg consists of the adductor longis (F) which is named after its job, to adduct the thigh, and the gracilis (G) which is the most superificial muscle of the inner thigh.

The adductor brevis and the pectineus are not labeled on the image.

Practice labeling the muscles using quizlet.

quadriceps muscles

A = sartorius | B = tensor fasciae latae | C = rectus femoris | D = vastus lateralis | E = vastus medialis | F = adductor longus | G = gracilis