INTRODUCTION: The alpine skier`s main "motor" is the potential energy, skiing velocities may require muscle forces exceeding the skier`s physical capacities. Some authors suggest that skiers have a "velocity barrier" (VB) above which performance worsens. Nevertheless, this concept has never been experimentally tested. The aim of this study was to experimentally test the existence of the VB and clarify its relationship with force production/applications capacities. METHODS: Fourteen skiers were equipped with ski-mounted force plates and a positional device. They ran a 2-turns section starting from 8 different heights. Three starting height conditions were kept for analysis: minimal entrance velocity (v min); entrance velocity allowing the better section time (vB ) and maximal entrance velocity (vmax ). Section time (T); on-snow force production (Ftot ) and on-snow proportion of Ftot applied radially (RF) were compared between the three conditions. Maximal voluntary isometric contraction (off-snow force production (MVC lab)) was also performed during another session to test its relationship with VB. RESULTS: The section time was reduced with increased velocity (lower T in v B vs. v min, p < 0.001) until a VB above which it started to worsen (lower T in v B vs. vmax , p = 0.002). On-snow force production (Ftot ) was higher in v B vs. vmin (p = 0.001) but not different between v B and vmax. Moreover, on-snow proportion of Ftot applied radially (RF) was higher in v B vs. v max (p = 0.005) and v min (p = 0.001). Lastly, a positive correlation between VB and MVC lab was demonstrated (r = 0.76; p = 0.003). DISCUSSION/CONCLUSION: The present study experimentally supports the existence of the VB. Both force production and force application capacities seem to limit the skiing effectiveness beyond the VB, leading to higher section time.
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