Musculo-articular stiffness is affected by the magnitude of the impulse applied when assessed with the free-oscillation technique

Abstract Musculo-articular stiffness (MAS) of the triceps surae can be assessed using the free-oscillation technique whereby an impulse is applied and the ensuing damped oscillations are recorded. The purpose of this study was to investigate if impulses of different magnitudes can affect the measurement of MAS. Twenty seven males (20.7±1.3 years) participated in this study. Three impulses of different magnitude (1.5, 2.3 and 3.1 N s) and four different loads (10, 20, 30, 40 kg) were employed in the assessment of triceps surae MAS, which was quantified and compared across loads and perturbations. As the magnitude of the impulse applied increased, the MAS ( p