Anatomy of the Quadriceps Muscles

The Quadriceps are a group of four muscles that sit on the anterior or front aspect of the thigh.

They are the Vastus Medialis, Intermedius and Lateralis and finally the Rectus Femoris.

The Quadriceps attach to the front of the tibia and originate at the top of the femur.

The exception to this rule is the Rectus Femoris which actually crosses the hip joint and originates on the pelvis.

In this diagram, the Vastus Intermedius and Rectus Femoris overlap.

The function of the Quadriceps as a whole is to extend the knee (straighten the knee).

The Rectus Femoris functions to extend the knee but also acts as a hip flexor because it crosses the hip joint.

Exercises that work the Quadriceps include:

• Leg extensions
• Lunges
• Leg press
• Squats