# Performance-Determining Variables of a Simulated Skimo
###### Abstract  
This study aimed to investigate the variables determining performance in a simulated on-snow Skimo sprint competition, and how their relationship with performance evolves from the individual time trial to the final. Fifteen national-level junior Skimo athletes (mean \(\pm\) SD: age, 17.8 \(\pm\) 2.5 years; maximal oxygen uptake, 66.8 mL-kg\({}^{-1}\cdot\)min\({}^{-1}\)) underwent a comprehensive assessment, involving submaximal and maximal endurance tests, maximal strength assessments, and a maximal sprint to determine maximal glycolytic capacity. Subsequently, a simulated sprint competition, comprising an individual time-trial and three heats (quaterfinal, semifinal, final), was conducted. Whole-body and upper body aerobic power (r = 0.69-0.93), maximal speed and power (r = 0.82-0.85) during the maximal performance test, as well as fat-free mass (r = 0.62-0.77) and body fat (r = -0.67)--0.77), exhibited significant correlations with performance in the time-trial, quarterfinal and semifinal. Moreover, maximal strength (r = 0.39-0.95) and transition duration (r = 0.52-0.85) showed moderate to large correlations with sprint performance. Overall, aerobic power, maximal speed and power, as well as fat-free mass, and body fat emerged as crucial determinants of Skimo sprint performance, while dynamic strength and the ability to transition quickly between sections also proved to be relevant factors. fat-free mass; maximal oxygen uptake; one-repetition maximum; peak oxygen uptake; maximal speed; power; skimo; sprint; VLmax +
Footnote †: journal: Medical  
downhill section on skis. A sprint competition consists of an individual qualification time-trial (TT), followed by three elimination heats of six athletes as the competition progresses (quarterfinals [QF], semifinals [SF], and finals [F]). Altogether, a sprint competition lasts for a total duration of approximately 3-4 h, including warm-up, qualification and heats, and cool-down [3]. Long-distance Skimo performance is connected to performance-determining factors such as high maximal aerobic power (VO\({}_{\text{2 max}}\)) [4] and corresponding speed (vVO\({}_{\text{2 max}}\)) [6], the fraction of VO\({}_{\text{2 max}}\) at ventilatory thresholds, while minimizing the energy cost of locomotion. Indeed, previous research revealed moderate-to-large correlations between Skimo race performance and physiological measures including VO\({}_{\text{2 max}}\), vVO\({}_{\text{2 max}}\) and VO\({}_{\text{2}}\) at the ventilatory thresholds [4; 6; 7]. The importance of VO\({}_{\text{2 max}}\) was further emphasized in a comparison between elite and sub-elite athletes, where the former had 8% higher VO\({}_{\text{2 max}}\)[6]. Depending on the race format, factors like anaerobic power, downhill skiing technique, low fat and body mass index, and effective equipment play crucial roles [5; 6; 7; 8]. Nevertheless, the existing literature on competitive Skimo racing is relatively scarce, primarily concentrating on long-distance events. However, with the introduction of shorter sprint competitions in the upcoming 2026 Winter Olympics in Milano Cortina, greater attention will be directed towards this format. This underscores the need for additional research. Previous research has demonstrated that achieving higher average speeds on uphill sections (lasting for approx. 120-150 s) and optimizing transition times between sections are important determinants of Skimo sprint performance [9]. To date, no studies have explored the physiological variables linked to performance in Skimo sprint racing, nor how these dynamics evolve throughout the competition stages (e.g., from individual time-trial to finals). Cross-country sprint skiing, which shares a similar format of repeated high-intensity efforts lasting around 2.5 to 3 min, highlights the critical importance of maximal aerobic capacity (i.e., both upper-body and whole-body) [10; 11; 12; 13], skiing efficiency, and a robust anaerobic energy system [14; 15; 16].