Which muscle is not part of the quadriceps group?

The pectoralis major is a large muscle located in the upper chest and is primarily responsible for movements of the shoulder joint, such as flexion, adduction, and rotation of the arm. It plays a key role in exercises involving pushing and lifting.

In contrast, the quadriceps group is composed of four specific muscles located in the front of the thigh, which include the vastus medialis, rectus femoris, vastus lateralis, and vastus intermedius. These muscles work together to extend the knee and play an important role in activities such as walking, running, and jumping.

Understanding the distinct functions and locations of these muscle groups helps clarify why the pectoralis major, being part of the upper body musculature, is not included in the quadriceps family, which is solely comprised of muscles in the thigh focused on knee extension.