Triceps Brachii The triceps brachii is a large fleshy muscle located on the back of the upper arm. It has three different heads that connect the scapula and upper humerus to the elbow. All three heads work together to extend the arm at the elbow as seen in the upward phase of the incline pushup.
Anterior Deltoids The deltoid is a thick, multipennate muscle that makes up the roundness of the shoulder. During an incline pushup, the anterior fibers of the muscle work together with the pectoralis major to powerfully flex and medially rotate the humerus bone of the upper arm.