In Plain English
The upper chest is the upper portion of your chest, running from the collarbone to the upper arm. It’s part of the larger pectoralis major and helps move your arm forward, across your body, and inward while creating fullness beneath the collarbones.
Technical Definition
The upper chest refers to the clavicular head of the pectoralis major, originating from the medial clavicle and inserting onto the lateral lip of the intertubercular groove of the humerus. Its superior fiber orientation gives it greater mechanical advantage during movements involving shoulder flexion and horizontal adduction performed from lower arm positions.

















