Under the auspices of the International Olympic Committee, a project involving three-dimensional analysis of skiing technique during the 1992 Olympic Winter Games (Albertville, France) was carried out. This part of the project focussed on the open field skating technique of the male skiers of the 50 kilometer race. Three synchronized, high-speed video cameras were used to record the motion of all racers as they passed a site on flat terrain which was approximately 15.7 km and 32.4 km (second lap) from the beginning of the race. Several skating techniques were used by the skiers, but analysis was limited to those using the open field technique and whose skating cycle fit within the boundaries of the field being analyzed (n = 17). Several kinematic variables were determined from the 3D data. Mean (± SD) cycle velocity was 6.32 ± 0.36 m/s; cycle length was 9.41 ± 0.85 m; and cycle rate was 0.67 ± 0.04 cycle/sec. On the flat terrain with relatively fast skiing velocity, the skis were placed at quite small angles with respect to the forward direction (-7.9 ± 2.7 deg and 6.9 ± 3.0 deg, strong and weak side ski, respectively). Knee, hip, elbow and trunk angles were determined throughout the skating cycles as well as poling and ski edging angles. Strong and weak side knee motions were similar with ranges of motion (ROM) of 34.2 ± 8.4 deg and 37.1 ± 9.7 deg, respectively. Considerable elbow extension occurs during the cycle with ROM of about 80 deg being typical. Trunk flexion contributes somewhat to the poling motion of the open field skate with trunk ROM of 28.3 ± 5.9 deg. Selected kinematic variables were inter-correlated. Several significant correlations (p < .05) were observed related to performance: cycle velocity was positively related to cycle length (r = .76) but not cycle rate; cycle velocity and cycle length were positively related to strong side knee extension (r = .48 and r = .51, respectively). Thus faster skiers on flat terrain tended to ski with longer cycle lengths which perhaps derived from more vigorous knee extension.
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