In this study: (a) an individualized mechanical model for measuring for measuring aerodynamic drag while ski racing through multiple gates had been developed, (b) energy dissipation caused by the aerodynamic per giant slalom gate had been estimated, (c) the relative contribution of energy losses caused by the drag in relation to the total energy loss during giant slalom gates had been investigated. In order to achieve that, extensive wind tunnel measurements, special Global Navigation Satellite System field measurements and extensive biomechanical computer modelling have been performed. It has been shown that in the giant slalom aerodynamic drag contributes only ~ 5% to 28% of the total energy dissipation per gate and that the aerodynamic drag ranges between 20 and 60 N. Based on the results can it be argued that the ski-snow friction in the giant slalom competition is more important than aerodynamic drag.
COBISS.SI-ID: 4296113
The work is a systematic review article, which deals with the biomechanical parameters that affect the performance of elite alpine skiers. For preparing the manuscript, we systematically reviewed all existing scientific literature, which is accessible through four global electronic databases with an additional manual search of reference lists. Based on qualitative analysis, we selected those articles that meet the defined conditions associated with the objectives of systematic review. By preparing the manuscript we gained knowledge and an overview of all so far known biomechanical parameters related to the performance of world-class skiers. In addition, we critically assessed which parameters are set in terms of the more important and wrote the shortcomings of existing studies and guidelines for new ones.
COBISS.SI-ID: 4450481
The aim of this study was to determine how an additional load influences the force-vs-time relationship of the countermovement vertical jump (CMVJ). The participants were asked to perform a CMVJ without and with additional loads of 10%, 20%, and 30% of their body weight (BW). The vertical component of the ground reaction force (GRF) was used to calculate the durations of the preparatory, braking, and acceleration phases, the total duration of the jump, force impulses during the braking and acceleration phases, average forces during the braking and acceleration phases, and the maximum force of impact at landing. Increasing the additional load prolonged both the braking and acceleration phases of the jump. The magnitude of the force systematically and significantly increased with the additional load. The force impulse during the acceleration phase did not differ significantly between jumps performed with loads of 20% and 30% BW. The results suggest that the optimal additional load for developing explosive strength in vertical jumping ranges from 20% to 30% of BW, with this value varying between individual subjects.
COBISS.SI-ID: 4404913