Abstract / Summary
Abstract Physical activity for blind or severely visually impaired people requires specific support. In alpine skiing, the required support is commonly provided by a human guide. The aim of the current study was to investigate possible differences between common guiding strategies with regard to the skiers’ body posture and orientation on the skis. An Inertial Motion Capture System based on inertial measurement units and equipped with 17 motion trackers was used to capture whole-body kinematics. From this, the position of the centre of mass in relation to the feet was determined for 18 participants in total. Differences in the centre of mass position projected vertically onto the slope were analysed using a linear mixed-effects model accounting for repeated measurements within participants. The model revealed a significant main effect of Guiding with the position of the centre of mass being significantly more backward during the rear-guide condition than during the front-guide condition (β = −0.048, p = .001). Significant main effects on overall values of the center of mass in relation to the feet were also found for Severity and Status: participants with residual vision showed greater values than blind participants, while participants with congenital visual impairment showed lower values than those with acquired visual impairment. Neither accustomed guiding technique nor skiing experience showed a significant main effect on the centre of mass in relation to the feet. The front-guide condition resulted in a more forward-oriented position of the centre of mass relative to the feet compared with the rear-guide condition. This position is considered relevant for readiness and control in alpine skiing and may also be of interest from a safety perspective, as backward lean has been associated with mechanisms of knee injury. These findings may inform the selection of guiding strategies and provide an initial empirical basis for developing more consistent, evidence-based guidelines for ski schools, clubs, and skiing associations.