Energy cost of free technique and classical cross-country skiing at racing speeds

Purpose: First, to measure the O-2 uptake ((V) over dot O-2) and the blood lactate concentration during cross-country skiing at competition speed. Second, to compare these entities for the free technique and the classical technique. Further, to establish the subjects' (V) over dot O-2max and the (V) over dot O-2 corresponding to the onset of blood lactate accumulation (OBLA, 4 mmol.L-1) during skiing, and finally to relate these entities to those of treadmill running. Methods: Five high-level female junior cross-country skiers with a mean (V) over dot O-2max of 63 mL.kg-(1.)min(-1) served as subjects in five tests: examination of the (V) over dot O-2max and the (V) over dot O-2 corresponding to the OBLA during up-hill cross-country skiing (both styles), inclined treadmill running, and a 6-km simulated cross-country ski race (both styles). Results: The (V) over dot O-2max obtained during up-hill cross-country skiing did not differ from that during treadmill running, nor did it differ between the two skiing styles. The peak heart rate wits significantly lower during uphill cross-country skiing than during treadmill running. During the simulated competitions, the (V) over dot O-2 averaged 84% of the (V) over dot O-2max or 95% of the (V) over dot O-2...