STRATEGIES IN ALPINE SNOWBOARD PARALLEL GIANT SLALOM - A GNSS FIELD STUDY WITH THE SWISS NATIONAL TEAM

INTRODUCTION: Many factors influence performance in alpine snowboarding. Until now, only very few have been scientifically researched. The aim of this study was to investigate the influence of known factors on performance from alpine skiing in alpine snowboarding. For example, the curve phase distribution and the turn radius were examined. METHODS: Using global navigation satellite systems (GNSS), 212 training runs with a total of 3716 turns were recorded in trainings of the Swiss Snowboard World Cup team in the 2020/2021 season (♀ = 5; ♂ = 3). The course setting characteristic was measured in each training session using RTK GNSS sensors. RESULTS: Concerning the influence of the turn phases, no significant difference were found. In flat and medium slopes, the larger the smallest radius of the turn was, the better (lower) the time for this section was. This difference has occurred in the female group. The speed of the athletes was lowest in steep terrain and became higher the flatter the slope was. While speed was increasing on average in toe-edge curves (M = 0.92 km/h, SD = 2.73, n = 1898), a loss of speed resulted on average in heeledge turns (M = -1.26 km/h, SD = 2.71, n = 1814), t(3710) = 24.372, p < .001. DISCUSSION/CONCLUSION: In contrast to alpine skiing, it seems that under certain circumstances, maintaining speed with a larger minimum turn radius is more important for a good performance (short run time), than aiming for a long gliding phase. The differences found between toe and heel edge turns are very clear. This knowledge can serve as a basis for developing technique, strategies as well as equipment in the sport

Giant Slalom: Analysis of Course Setting, Steepness and Performance of Different Age Groups - A Pilot Study

Introduction: Giant slalom is the core discipline of alpine skiing, and each race has its own specific course and terrain characteristics. These variations may explain differences in the speed and time per turn profiles, which are essential for performance development and injury prevention. This study aims to address the differences in course setting and steepness of the different course sections (flat-medium-steep) and compare them to the performance parameters among young (U12, U14, U16) and older (U18, U21, elite) male athletes. Methods: The study examined a total sample size of 57 male athletes; 7 from elite level, 11 from U21, 13 from U18, 6 from U16, 13 from U14, and 7 from U12. The athletes wore a portable global navigation satellite system (GNSS) sensor to extract performance parameters. The course profiles and gate positions of nine runs were measured with differential GNSS. The runs were divided into flat, medium and steep sections. From the performance parameters (speed, time per turn, etc.) and the course setting variables, the mean value per section was calculated and used for the further analysis. Results: In total, 192 run sections from 88 runs were recorded and analyzed. Comparisons between course settings in young and older classes showed no significant differences. However, the turning angles and horizontal gate distances were smaller in flat sections. Average speed (49.77 vs. 65.33 km/h) and time per turn (1.74 vs. 1.41 s) differed significantly between young and U21/elite categories. In medium terrain sections U21 and elite athletes spent more time in the gliding phase compared to all other athletes. Discussion: It seems to be a reasonable that, given similar course setting and steepness, speed increases concurrently with the technical and tactical skills of the athlete. Moreover, the finding that the elite athletes spent more time in the gliding phase could be crucial for understanding technique and performance development in young athletes

Design parameters and landing impacts of snow park jumps in Switzerland

Objectives: Design parameters and landing impacts for selected snow park jumps in Switzerland were compared with the parameters recommended to increase the jumps’ safety by the Swiss Council for Accident Prevention (BFU). High impact zones were identified to help snow park shapers optimize the design of their jumps. A rough estimate of the influence of snow hardness on landing impacts was also provided. Design: During the 2020/2021 winter season three-dimensional geometries of 23 jumps were captured using differential global navigation satellite system and terrestrial laser scanning. A point mass model was used to numerically calculate trajectories. The equivalent fall height (eFH) was used to quantify landing impacts and an empiric snow-deformation function was applied to take the effect of snow hardness into consideration. Workshops were held to discuss results and transfer findings. Methods: 2D-profiles of the jumps were estimated by projecting the captured 3D position data onto the longitudinal cross-section plane. Table and landing geometry were smoothed and interpolated to a spatial resolution of 0.1 ​m, while the kicker was fitted with a 2nd order polynomial. Trajectories were numerically calculated for take-off speeds from 6 to 17.6 ​m ​s−1 including aerodynamic forces using the Runge-Kutta method. The calculated eFH at the landing points were used to divide the landing into low-impact, medium-impact, and high-impact zones. Results: Medium sized jumps had a low-impact zone of sufficient length (>6 ​m) and eFH smaller than 1.5 ​m throughout the entire table meeting the BFU recommendations. Nevertheless, critical eFH larger than 1.5 ​m, were obtained when take-off speeds increased by only 1.14 ​m ​s−1. Large jumps had low-impact zone lengths in accord with the recommendations (>9 ​m), but high eFH (2.3–3.4 ​m) occurred for table landings. 10 of the 13 XL-jumps had long low-impact zones of approximately 12–15 ​m. Besides the risk of high impact landings towards the end of the landing area, as found similarly for the smaller jumps, portions of XL-jumps had very high eFH (2.6–4.6 ​m) for table landings. Conclusions: The study confirmed the existing BFU recommendations of size categories, design parameters and landing impacts limits as prevalent and practicable and provided knowledge for future safety recommendations. Modifying table geometries and taking measures to limit the in-run speeds would help reduce landing impacts, and the hazard due to hard snow conditions should also be considered

Giant slalom ::analysis of course setting, steepness and performance of different age groups — a pilot study

Introduction: Giant slalom is the core discipline of alpine skiing, and each race has its own specific course and terrain characteristics. These variations may explain differences in the speed and time per turn profiles, which are essential for performance development and injury prevention. This study aims to address the differences in course setting and steepness of the different course sections (flat—medium—steep) and compare them to the performance parameters among young (U12, U14, U16) and older (U18, U21, elite) male athletes. Methods: The study examined a total sample size of 57 male athletes; 7 from elite level, 11 from U21, 13 from U18, 6 from U16, 13 from U14, and 7 from U12. The athletes wore a portable global navigation satellite system (GNSS) sensor to extract performance parameters. The course profiles and gate positions of nine runs were measured with differential GNSS. The runs were divided into flat, medium and steep sections. From the performance parameters (speed, time per turn, etc.) and the course setting variables, the mean value per section was calculated and used for the further analysis. Results: In total, 192 run sections from 88 runs were recorded and analyzed. Comparisons between course settings in young and older classes showed no significant differences. However, the turning angles and horizontal gate distances were smaller in flat sections. Average speed (49.77 vs. 65.33 km/h) and time per turn (1.74 vs. 1.41 s) differed significantly between young and U21/elite categories. In medium terrain sections U21 and elite athletes spent more time in the gliding phase compared to all other athletes. Discussion: It seems to be a reasonable that, given similar course setting and steepness, speed increases concurrently with the technical and tactical skills of the athlete. Moreover, the finding that the elite athletes spent more time in the gliding phase could be crucial for understanding technique and performance development in young athletes