A Composite Biomechanical Index for Dynamic Postural Control in Canadian Canoe Athletes

Dynamic postural control in Canadian canoeing depends on coordinated load distribution and center of pressure regulation across three support points in a highly asymmetrical kneeling posture. However, the integrated organization of these biomechanical domains under varying stability demands remains poorly characterized. This exploratory study examined 13 Canadian canoeing athletes using three synchronized strain-gauge force platforms during a standardized canoe-specific kneeling position under stable and unstable support conditions. Three dynamic variables, percentage load distribution (%DCA), dynamic force (N.kg⁻¹), and center-of-pressure displacement (Dynamic SigmaPath), were assessed simultaneously. Principal component analysis showed that PC1 (62.5% variance) and PC2 (24.1% variance) captured the main structure of postural control, with Dynamic SigmaPath displaying loading patterns opposite to the percentage load distribution and force. Exploratory K-means clustering (k=2) suggested moderate organization into two biomechanical patterns. Correlation analyses revealed significant associations between load-distribution metrics and Dynamic SigmaPath (ρ=0.657 and p=0.015), and between force production and load-distribution asymmetry (ρ=-0.635 and p=0.020). These findings indicate that biomechanical affinity, quantified through multivariate analysis, characterizes athlete-specific postural-control strategies. A Composite Biomechanical Index is proposed as an exploratory framework for describing postural-control strategies and generating hypotheses regarding athlete monitoring and crew compatibility in paddling sports.