Relationship between performance and support kinetics during an alpine ski turn


This research project is a continuation of Thomas Falda-Buscaiot's thesis work carried out at the LIBM laboratory under the direction of F. Hintzy. The aim was to develop and validate an on-board force platform for the analysis of in situ mechanical stresses applied in alpine skiing, in all three dimensions. The originality and relevance of this platform is that it doesn't distort practice (sufficiently thin 6.0 mm, light 1.4 kg, two-part construction allowing the ski to be flexed under the boot).

Current knowledge focuses on the vertical load during a turn, showing a load increase at edge grip, a plateau during the driving phase and a load decrease at edge release between two lightening periods (Lüthi 2003). The maximum load value during the turn is the only marker studied in the literature on this force signature. It varies according to the technique used (Supej 2002), the race layout (Nakazato 2011), and potentially the level of performance (Supej 2010, Supej 2011, with indirect measurements). Other studies suggest that the force signature is also influenced by slope (Falda-Buscaiot et al. 2017).

The objective of this thesis is to complete the description of the force signature, (i) by calculating new parameters describing the evolution of the force kinetics in turns and (ii) by adding the medial-lateral and antero-posterior components as well as the force moments. (iii) Then to test the sensitivity of these parameters to variations in the level of performance, the characteristics of the track and the trajectory strategies used by the skier.