Effect of Class, Sex, and Final Rank on the Time Distribution Across Terrains During Para Cross-Country Skiing Races

Para cross-country (XC) skiers compete in race courses with different terrains (uphill, downhill, and undulated) across several classes in three categories (visually, standing, and sitting impaired). The objectives were to investigate (1) the distribution of distance and relative race time spent in different terrains (%RT_Terr) across different races, and (2) the association of class with %RT_Terr while adjusting for sex and final rank. Sixty-eight Para XC skiers were tracked with GNSS sensors during middle- and long-distance races at two World Championships. Linear mixed models were used to investigate the association of class with %RT_Terr while adjusting for sex and final rank. The relative distance covered in each terrain (uphill: 17%-42%, downhill: 27%-46%, and undulated: 12%-56%) and corresponding %RT_Terr (uphill: 20%-58%, downhill: 16%-30%, and undulated: 12%-57%) varied across races. Nevertheless, individual %RT_Terr was relatively consistent among the Para cross-country skiers within each race. There was no significant effect of class on %RT_Terr for sitting and standing skiers, indicating that the differences between classes are similar or smaller than those between individual skiers within a class. In contrast, there was a significant effect of class on %RT_Terr for the visually impaired skiers (p < 0.019). Furthermore, lower ranked skiers spent ∼0.1-0.25%pt more time in the uphill terrain per rank (p < 0.001 for all categories) and ∼0.05-0.25%pt less time in the downhill terrain per rank (p < 0.01). Finally, women skiers spent significantly more of their %RT_Terr in the uphill terrain (∼1.3-2.3%pt, p < 0.04) and less in the downhill terrain (∼1.0-2%pt, p < 0.01). Given the small sample size within most classes, our findings need to be interpreted with caution.