Neuromechanical Biomarkers

This chapter examines neuromechanical biomarkers as objective indicators of tissue state, with emphasis on muscle tone, stiffness, and elasticity. It clarifies the physiological meaning of each construct and explains how these properties emerge from the interaction of neural drive, muscle architecture, extracellular matrix organization, fluid balance, and viscoelastic tissue behavior. The chapter also reviews the main technologies used to quantify these parameters, including myotonometry, elastography, tensiomyography, and related biomechanical approaches, highlighting what each method truly measures and where interpretation can fail. Particular attention is given to measurement validity, reliability, and the major confounders that influence results, such as posture, probe placement, contraction state, hydration, temperature, prior exercise, pain, and operator technique. Finally, the chapter translates this evidence into practical guidance for sport and clinical contexts, helping readers interpret neuromechanical signals with greater rigor, caution, and applied relevance.