Identification of the optimal racing line for top male athletes on a segment of a World Cup downhill alpine ski slope using tracking data

Abstract

Using tracking data we can identify the optimal racing line for top male athletes on the famous S-curved segment (Brueggli-S) of the downhill FIS world cup track “Lauberhorn” in Switzerland. For this, we have measured and analysed training runs, measured on a single day, of 10 world class athletes. Based on curvatures derived from the tracking data, a large variation in racing lines adopted by the athletes was observed. Each of the detected racing lines share a similar pattern: The maximum curvature in the first curve is strongly correlated with the minimum curvature of the second curve. We have found that, for the athletes under investigation, the overall best racing line is characterized by a defined ratio of the maximum curvature of the first to the second curve. We claim that the observed correlation, as well as the optimal ratio of curvatures, is universal for a class of athletes with nearly identical performance levels. If and how this ratio varies for different classes of athletes (i.e. U10, U12 or U16 athletes) is an as yet unanswered question and remains open to further investigation.