“…Among the different variables that can be measured as indicators of ergonomic performance and biomechanical risk when standing, trunk oscillations, which directly reflect information about postural sway (Reynard et al, 2019 ) represent valuable variables that can be associated with fatigue emergence, and, as a result, risk increases (Dupuis et al, 2021 ). Postural sway has been frequently used for the characterization of ergonomics (Padula and Coury, 2003 ; Leban et al, 2017 ; Arippa et al, 2022 ). Stability and regularity of trunk oscillations is of key importance for the characterization of the motor performance during a biomechanical task (Granata and England, 2006 ); following this perspective, different methodological approaches, such as the extraction of the maximum Lyapunov exponents (Granata and England, 2006 ) or the computation of the mutual information (Anagnostou, 2022 ) have been introduced to capture stability- or regularity-related indicators from trunk movements or from the Center of Pressure (CoP) displacement; given the rather complex nature of the mechanisms of controlling balance while standing, which involves nonlinear effects.…”