The term “Core” has become all the rage in the fitness industry; both athlete and fitness enthusiasts alike are aware of the need to maintain a solid foundation. However, the meaning of the word may be very different depending on the person. For instance, at the collegiate and clinical levels, the term represents the more than 30 muscles that act on the motion segments of the hip and spine. But in a gym, a core class may be comprised primarily of crunches and multiple variations of supine trunk flexion. Arguably, the core concept is appropriately applied in the relationship of stability and energy transfer, where the inner unit functions with the global stabilizers and movers of the outer unit.