The importance of shooting performance in relation to the complex performance in biathlon is increasing due to the introduction of new competition variants with proportionately more bouts of shooting compared to skiing. Besides shooting position, targeting, breathing technique and triggering (Nitzsche, 1998), body sway (e.g. Bozsik & Bretz, 1994) and stance stability (Sattlecker et al., 2009) can be considered as main performance variables. The aim of the current study is to analyse the relationship between body sway, various body angles and shooting position as well as their influence on the muzzle movements and shooting results. Therefore a specific measuring station was developed. In previous projects (e.g. Nitzsche, 2009), specific sensors were used, to measure forces between athlete and rifle (e.g. forces on the trigger and on the butt plate) as well as movements and accelerations on the muzzle. In the current study, a stabilometric platform (footscan® by RSscan) and a 2D video analysis system (Simi Motion) were integrated. Through synchronization of all three constituent parts of the measuring station by determining the exact moment of the shot using a piezoelectric sensor, it is possible to analyse the relation of all measured variables. Therefore, the data were processed by merger.biathlon (WiFa, University of Leipzig). In the current study, 117 German biathletes from all age groups were analysed. Each biathlete had to shoot 4 series in standing position, 2 without and 2 with physical load. Analysed variables of body sway were the deviation of the centre of pressure (COP) in shooting direction (COP_X, mm) and 90° to shooting direction (COP_Y, mm), as well as the load distribution between front/rear foot (LD_FR, %) and heels/toes (LD_HT, %) over one second before the shot. These variables were set in relation to shooting score (1-10) depending on age and physical load. With physical load, the results showed significant dependencies between age and body sway in both motion axis (COP_X -0,221; p = 0,018; COP_Y -0,297; p = 0,001). Body sway in younger athletes is significantly greater than in older athletes. For body sway in comparison with shooting results under physical load, the results show correlations in both motion axis (COP_X -0,201; p = 0,032; COP_Y -0,366; p < 0,001). Higher body sway in both motion axis leads to lower shooting scores. Also, the results showed less body sway with greater load distribution on the front foot (-0,322; p < 0,001). Even though the correlations are low (e.g. due to the complexity of biathlon shooting), the measuring station has proven to be very useful in order to quantify the main performance variables of shooting and their relation to each other as well as their influence on the shooting results.
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