Toward a Unified Definition of the Human Core: The Total Body Core Model

This technical report proposes a unified, system-level definition of the human core integrating anatomical, biomechanical, and functional perspectives. Despite the central role of core function in spinal stability, movement efficiency, and injury reduction, no comprehensive definition has been consistently adopted across rehabilitation, fitness, and performance domains. Relevant literature on core stability and lumbopelvic-hip complex function is reviewed, and the Total Body Core Model (TBCM) is introduced as an integrative conceptual framework informed by cross-disciplinary research and long-term practitioner observation. The model provides a structured synthesis intended to support scholarly dialogue, guide future investigation, and facilitate empirical evaluation of integrated core function. The TBCM organizes core function into four interdependent layers (deep stabilizing systems, structural stabilizers, myofascial cross-bridges, and peripheral sensory modulators), integrating muscular, fascial, neuromechanical, and proximal-distal interactions within a single framework. The model is proposed as a foundational step toward establishing a standardized operational definition of the human core.