engleski

BIOMECHANICAL FIELD STUDY OF SLALOM TURN DURING SECOND RUN SNOW QUEEN TROPHY RACE

Slalom is a challenging alpine ski discipline from both tactical and technical perspective. Biomechanical factors influence the tactics employed during the race and can affect success. We performed biomechanical field study investigating velocity at different sections of slalom turn, angles of lower extremity during turn performance and their relation to projection of centre of mass during FIS World Cup Race Snow Queen Trophy. Kinematic analysis of slalom turn was performed to compare the correlations between angles in joints of lower extremities, distance of centre of mass during different segments of turn and velocity of skiing during turn in competitor level skiers. The Ariel Performance Analysis System was used to calculate the 3D kinematic data for 30 elite alpine skiers participating in the second run. Results suggest highest variability between competitors in velocities achieved during turn initiation. Moreover, we found correlation between competitors’ velocity during turn initiation and angle in the knee joint (r=0, 56). Additionally, velocity during initial phases of turn correlated with centre of mass with respect to inner ankle joint (r=0, 63), as well as with outer ankle joint (r=0, 58). Moreover, angles between upper and lower leg correlated significantly with velocity during all phases of slalom turn, while we found no correlation whatsoever between competitors’ upper leg and core and velocity. Significant correlation was also seen between velocity during all three phases of ski turn and centre of mass during middle part of the turn in relation to both inner and outer ankle joint. Our data suggest that competitors with lower velocity at the beginning of the turn opted for a less direct trajectory. But due to configurational differences and different ways gates are positioned through entire race, competitor is not able to use the same tactics through an entire slalom race, so velocity over one turn might not have an overwhelming influence on the velocity of the race in a whole. To conclude, many different biomechanical factors influence the performance during slalom race and competitor must take into account intricate interactions between them under different conditions to minimize the descent time.

slalom, kinematic, velocity of skiing, line of skiing, skiing technic

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