INTRODUCTION; Vertical jumps are highly standardized actions representing action of leg extensors in different contraction conditions: concentric, slow stretch-shortening cycle (SSC) and fast SSC action. Based on previous observation (not published) it was expected that different slalom courses will be related to different vertical jumps. This would reveal specific motor structure that may favor success in specific Slalom course and can be consequently used for conditioning preparation. The aim of the study was to analyze different slalom courses if they differ regarding typical contraction conditions assessed with vertical jumps. METHOD: Nine alpine skiers, members of Slovenian A (WC) and B (EC) national team and trained in slalom, volunteered in the study. They jumped squat jump (SJ), counter-movement jump (CMJ), and drop jumps from 25 (DJ25) and 45 cm (DJ45) high platform. Ground reaction force with Kistler force platform was measured and analyzed for jumping height (H_Jump), braking (T1_Jump) and lifting time (T2_Jump), mean acceleration during braking (A1_Jump) and during lifting (A2_Jump) phase. A1 and A2 in SJ corresponded to the first and the second half of the take-off time, For SJ and CMJ, mean acceleration during first 100 ms when F(t) curve increased over body weight was calculated as well. Four different ski courses were set: smaller inclination with narrow corridor (P_N) and wider (P_W) corridor, and steeper with narrow (S_N) and wider (S_W) corridor for gates. All courses were driven twice, the best time was used for analysis. Course time was normalized to average time of all four courses. RESULTS: Results are presented in Table 1. Statistically significant (P<0.05) correlations between different slalom courses and vertical jumps were observed only in both wide courses but not in narrow ones. However, the signs of correlation coefficients were in opposite direction. SJ was not correlated to any course. DISCUSS1ON: Both narrow courses were the most often training settings in the subjects while the S_W was the least present. However, it was the most related to the vertical jumps. The structure of relationships with S_W showed that CMJ was most related including Parameters describing braking and lifting phase. in DJs, only lifting part was presented. At the moment, we can't explain the negative correlations between jumps and P_W. Interestingly, no relationship to SJ Parameters was found in any ski course. CONCLUSION: We concluded that no relationship between trained courses and vertical jumps imply that skiing technique was not founded on conditional factors. This is based on significant correlations between jumps and S_W, which may be interpreted as application of technical solution based on conditioning since no automatic skiing program was provided due to lack of training of that course. From obtained results it is not possible to say whether technical training or conditioning was not appropriate.
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