Effect of ski geometry on aggressive ski behaviour and visual aesthetics: equipment designed to reduce risk of severe traumatic knee injuries in alpine giant slalom ski racing. Issue 1 (24th November 2015)

• Record Type: Journal Article
• Authors: Kröll, Josef; Spörri, Jörg; Gilgien, Matthias; Schwameder, Hermann; Müller, Erich
• Is Part Of: British journal of sports medicine. Volume 50:Issue 1(2016)
• Page Start: 20
• Page End: 25
• Publication Date: 2015-11-24
• Subjects: Injury prevention -- Alpine skiing -- Biomechanics; Sports medicine -- Periodicals; 617.1027
• DOI: 10.1136/bjsports-2015-095433
• Languages: English
• ISSNs: 0306-3674

Abstract

Abstract : Background/Aim: Aggressive ski-snow interaction is characterised by direct force transmission and difficulty of getting the ski off its edge once the ski is carving. This behaviour has been suggested to be a main contributor to severe knee injuries in giant slalom (GS). The aim of the current study was to provide a foundation for new equipment specifications in GS by considering two perspectives: Reducing the ski's aggressiveness for injury prevention and maintaining the external attractiveness of a ski racer's technique for spectators. Methods: Three GS ski prototypes were defined based on theoretical considerations and were compared to a reference ski (Pref ). Compared to Pref, all prototypes were constructed with reduced profile width and increased ski length. The construction radius (sidecut radius) of Pref was ≥27 m and was increased for the prototypes: 30 m (P30 ), 35 m (P35 ), and 40 m (P40 ). Seven World Cup level athletes performed GS runs on each of the three prototypes and Pref . Kinetic variables related to the ski-snow interaction were assessed to quantify the ski's aggressiveness. Additionally, 13 athletes evaluated their subjective perception of aggressiveness. 15 sports students rated several videotaped runs to assess external attractiveness. Results: Kinetic variables quantifying the ski's aggressiveness showed decreased values for P35 and P40 compared to Pref and P30 . Greater sidecut radius reduced subjectively perceived aggressiveness. External attractiveness was reduced for P40 only. Conclusions: This investigation revealed the following evaluation of the prototypes concerning injury prevention and external attractiveness: P30 : no preventative gain, no loss in attractiveness; P35 : substantial preventative gain, no significant loss in attractiveness; P40 : highest preventative gain, significant loss in attractiveness.