Analysis of a sprint ski race and associated laboratory determinants of world-class performance.

This investigation was designed to analyze the time-trial (STT) in an international cross-country skiing sprint skating competition for (1) overall STT performance and relative contributions of time spent in different sections of terrain, (2) work rate and kinematics on uphill terrain, and (3) relationships to physiological and kinematic parameters while treadmill roller ski skating. Total time and times in nine different sections of terrain by 12 world-class male sprint skiers were determined, along with work rate and kinematics for one specific uphill section. In addition, peak oxygen uptake (VO(2peak)), gross efficiency (GE), peak speed (V(peak)), and kinematics in skating were measured. Times on the last two uphill and two final flat sections were correlated to overall STT performance (r = ~-0.80, P < 0.001). For the selected uphill section, speed was correlated to cycle length (r = -0.75, P < 0.01) and the estimated work rate was approximately 160% of peak aerobic power. VO(2peak), GE, V(peak), and peak cycle length were all correlated to STT performance (r = ~-0.85, P < 0.001). More specifically, VO(2peak) and GE were correlated to the last two uphill and two final flat section times, whereas V(peak) and peak cycle length were correlated to times in all uphill, flat, and curved sections except for the initial section (r = ~-0.80, P < 0.01). Performances on uphill and flat terrain in the latter part were the most significant determinants of overall STT performance. Peak oxygen uptake, efficiency, peak speed, and peak cycle length were strongly correlated to overall STT performance, as well as to performance in different sections of the race.