INTRODUCTION: Laterality affects human motorics in both unilateral and bilateral movements. Right foot preference is manifested in approximately 80% of the overall population (Porac & Cohen, 1981). The influence of lateral preference on the quality of sport and basic movements has been investigated in several papers (e.g., Vaverka, 2005). Based on the personal experiences of skiers, we can assume that most of them favor either the turn to the right or the turn to the left. It can be expected that lateral preference with regard to the lower extremities can influence the quality of a ski turn to the right or left. We can also set up an alternative hypothesis and assume that there are no differences in the execution of a ski turn to the left and right in very experienced and long-term trained skiers. METHOD: Six very skilled skiers, all with right foot preference, participated in this research. They performed six symmetrical carving turns (three to the left and three to the right, to make a total of 18 left and 18 right turns) on a track situated in a fall line. Analysis of the final reaction force F2 (t) provided us with Information with regard to the duration of each turn, the magnitude of the force Impulse, and the maximal force produced in right and left turns. We also computed indices of symmetry {IS = R/L leg) from the obtained data and then performed a statistical analysis on all variables (t-test, Wilcoxon test, Mann-Whitney U test). RESULTS: The results of the statistical analysis showed significant differences between left and right turns in all observed variables. The left turn (where the right "preferred" leg is dominant) took a longer time (1.54 versus 1.17 s), with a greater force impulse (760 versus 337 Ns), and greater maximal force (1710 versus 1212 N). The indices of symmetry were in the range of 0.41 - 0.73. DISCUSSION: From the point of view of practice, we can ascertain that greater emphasis is put on the execution of a left turn, where the right "preferred" leg is dominant. The observed findings are surprising with regard to the fact that the subjects of the research were very skilled skiers (two top national racers among the set) with lifelong top-level skiing experience. CONCLUSION: The lateral preference was manifested in symmetrical carving turns by a longer duration of the turn, and by the greater force produced in the left turn where the right (dominant) leg is outer-most in this turn. The results indicated that the main regulator of a ride's speed is the left turn. The dynamometry of the ski turn seems to be an appropriate method for an assessment of the quality of the execution of a turn.
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