Developing a Fundamental Theoretical Definition for Athletic Injury

Logical Reasoning, Boundary Testing, and the Importance of Necessary and Sufficient Conditions

Abstract

The absence of a conceptually robust theoretical definition of athletic injury is problematic in sports science and medicine, as such a definition provides an essential framework for scientifically studying this concept. Existing definitions are overly vague and lack logical coherence, failing to provide sufficient frameworks for the development of more precise understandings, operationalisations (including mathematisation) and identifications of athletic injury, which undermines the critical scientific principles of predictability, falsifiability, and reproducibility. Furthermore, related concepts that are often integrated into various operational definitions of athletic injury, such as pain and participation in sports, are commonly conflated as fundamental criteria. To address these concerns, this article proposes a new theoretical definition of athletic injury, developed through a systematic process of logical reasoning. This approach employs well-established tools such as thought experiments, boundary tests, and logical arguments to test for logical coherence in existing definitions, and to establish a set of necessary and sufficient conditions for an athletic injury to occur. Through this process, commonly conflated concepts are disentangled, and the development of a more refined conceptualisation and definition of athletic injury is achieved, capturing its fundamental essence as "Tissue damage and loss of physical function during sports participation, resulting from rapid or repetitive transfer of kinetic energy, that is not a normal part of the physical training and positive adaptation process, but exceeds the threshold of mechanical and physiological tolerance. This is dependent upon the nature and degree of tissue damage sustained." By introducing a demarcating threshold of tissue damage and loss of physical function to distinguish athletic injury from non-injury, this definition aligns athletic injury more closely to the definitions of injury proposed by the World Health Organization and International Classification of Diseases. Furthermore, by grounding athletic injury in objectively measurable physical parameters that can be appropriately mathematised for inclusion in mathematical (e.g., predictive) models, and that also function within a mathematically unified physics-based framework, the predictability, falsifiability, and reproducibility of athletic injury research can be enhanced. Altogether, this transforms athletic injury from a vague concept, subject to inconsistent interpretations and applications i.e., bias, into a mathematical object with well-defined semantics and well-founded logic, guiding the formation of more precise, ideally tissue-specific, operational definitions of athletic injury. Over time, this will aid in the development of objective measurement tools that can more accurately assess and distinguish athletic injuries from non-injuries, supporting scientific advancements in the identification, measurement and prediction of athletic injuries.