| Title | U23 Cross-Country Ski World Championship 2018 Sprint Prologue: Relative Terrain Performances and Sex Differences |
| Author | Bucher, Elias; Bruhin, Björn; Meier, Yasmin; Steiner, Thomas; Wehrlin, Jon |
| EHSM Authors | Bucher, Elias, elias.bucher@baspo.admin.ch |
| Year | 2019 |
| Abstract | INTRODUCTION: The cross-country ski sprint prologue involves a 2 – 4 minute long effort on varying terrain with only the top 30 skiers advancing to the subsequent heats. Qualification success not only depends on physiological and technical capacity, but also on optimal pacing strategy and appropriate relative efforts in the various terrains (Sandbakk et al., 2011). METHODS: During the U23 Cross-Country Ski World Championships 2018 freestyle sprint prologue in Ulrichen (SUI), skiing performance in flat, uphill and downhill terrain was analyzed for female (N = 43) and male (N = 64) skiers using time-synchronized video recordings. Relative performance indices for the three different terrains were calculated (Vterrain / Vaverage). A Spearman’s rank order correlation for the terrain indices ranking and overall prologue ranking was calculated and potential sex differences regarding performance in the various terrains were analyzed by ANOVA. Table 1. Spearman’s rank correlation coefficients for terrain index rank and overall prologue performance and corresponding level of statistical significance. Overall prologue rank Women Men Flat index rank -0.42** -0.24 Uphill index rank 0.59*** 0.57*** Downhill index rank -0.39* -0.50*** *p < .05; **p < .01; ***p < .001 RESULTS: Terrain index rank correlations are shown in Table 1. Male skiers demonstrated higher uphill indices than females 0.62 ± 0.01 vs. 0.57 ± 0.02 (p < .001), with no significant differences found for flat and downhill terrain indices (both p > .05). DISCUSSION: A higher relative skiing effort for uphill terrain appeared to be correlated to overall rank in the investigated cross-country ski sprint prologue for both female and male skiers. At the same time, relative skiing performance in flat and downhill sections were negatively correlated to overall rank in the prologue, indicating a smaller relative effort and/or significance. Furthermore, male skiers demonstrated higher relative skiing velocities in the uphill track sections compared to female skiers, which was not observed regarding relative flat and downhill terrain efforts. CONCLUSION: The current study identified higher relative velocities invested during uphill terrain in faster skiers compared to slower skiers at an international freestyle sprint skiing competition, supporting the importance of performance indicators for uphill terrain. In addition, the difference in the relative effort investment between female and male skiers appeared to be only present in uphill terrain, indicating a sex differences in performance concerning uphill relevant performance factors and/or pacing strategy. REFERENCES Sandbakk, O., Ettema, G., Leirdal, S., Jakobsen, V., Holmberg, HC. (2011) Analysis of a sprint ski race and associated laboratory determinants of world-class performance. European Journal of Applied Physiology 111:947-957. |