The Contribution of Ski Poles to Aerodynamic Drag in Alpine Skiing

• Published in: Applied sciences Vol. 13; no. 14; p. 8152
• Main Authors: Supej, Matej, Kalén, Anton, Verdel, Nina, Ogrin, Jan, Holmberg, Hans-Christer
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01.07.2023
• Subjects: air resistance; Analysis; biomechanics; Centre - Centre for Sports and Performance Technology (SPORTC); Centrumbildning - Centrum för idrotts- och prestationsteknologi (SPORTC); coefficient of aerodynamic drag; cross-sectional area; Equipment and supplies; force; Fysioterapi; kinetics; Physiotherapy; Ski equipment; ski posture; Skiing; skiing position; Skis and skiing; Skövde Artificial Intelligence Lab (SAIL); Standard deviation; tuck; wind tunnel
• ISSN: 2076-3417; 2076-3417
• DOI: 10.3390/app13148152

The present study was designed to determine the contribution of the cross-sectional area of the ski poles (Sp) to the total aerodynamic drag during alpine skiing. At three different wind speeds in a wind tunnel, 10 skiers assumed typical alpine skiing postures (high, middle, and tuck), and their frontal aerodynamic drag was assessed with a force plate and their cross-sectional area, along with that of their ski poles, determined by interactive image segmentation. The data collected were utilized to examine intra-subject variation in Sp, the effects of Sp on the coefficient of aerodynamic drag (Cd), and the product of Cd and total cross-sectional area (Cd∙S. The major findings were as follows: (i) Sp ranged from 0.0067 (tuck position) to 0.0262 m2 (middle position), contributing 2.2–4.8% of the total cross-sectional area, respectively; (ii) Sp was dependent on wind speed in the high and middle positions; (iii) intra-subject variations ranged from 0.0018 m2 (27.6%) in the tuck position to 0.0072 m2 (30.5%) in the high position; (iv) Sp exerted a likely effect on Cd and Cd∙S. The extensive intra- and inter-skier variability in Sp can account for as much as ~5% of the total frontal cross-sectional area and future investigations on how elite skiers optimize their positioning of the poles in a manner that reduces aerodynamic drag are warranted.