What is the Core? When you hear the term “core,” abdominal muscles may immediately come to mind. However, the core actually comprises much more than just the abs. The core includes all the deep and superficial muscles used to stabilize, align, and move the trunk of the body as well as the pelvis and hips. The core is where the body’s center of gravity is located, and is the root source of all movement whether we’re talking about trunk movement or movement of the extremities.