Technique differences between male and female cross-country skiers while whole body, upper body and arm poling in a ski ergometer

Abstract

Introduction: The anthropometric and physical differences between men and women should not only influence the capacity to generate power and energy, but may also lead to differences in technique in a whole-body endurance sport like cross-country skiing. Since the upper body plays a crucial role in this sport, specific training of the arms and trunk is of importance. However, little is presently known concerning gender differences in the technical execution of the double-poling movement and how this coincide with variations in exercise efficiency.
Purpose: To characterize gender differences in the technical execution of upper body poling and exercise efficiency between whole-body (WP), upper-body (UP) and arm poling (AP) among elite cross-country skiers.
Methods: Ten male and ten female elite cross-country skiers, matched for international performance level, completed three incremental submaximal tests and a 3-min all-out test on a Concept2 SkiErg in all poling modes. Power output was measured with the ergometer’s internal software. Respiratory variables were assessed employing open-circuit indirect calorimetry. Movement data from eleven passive reflective markers on the ergometer and body was captured by the Qualisys motion capture system. The regression lines of submaximal oxygen uptake on power output were used to compare exercise efficiency.
Results: To produce the 87% (152±28 vs 285±34W in WP), 97% (110±19 vs 216±34W in UP) and 103% (69±12 vs 140±20W in AP) higher power outputs during the 3-min test, men exhibited shorter poling times and used greater shoulder and elbow extension at the start of poling (all P<0.05). There were no gender differences in the shoulder and elbow angles at the end of the poling phase. The hip angles did not differ between the men and women at the start of poling, but were significantly smaller for the men at the end of the poling phase, resulting in a larger trunk range of motion for the men (all P<0.05). The relationship between oxygen uptake and power output during the three submaximal sessions did not differ between the men and women for any of the poling modes.
Conclusions: The higher power outputs of the men coincided with significant gender variability in the technical execution of all poling modes and a favourable distribution of muscle mass in arms. The tendency towards greater angular range of motion of the trunk shoulder and elbow joints executed over relatively less time among men indicate a more explosive poling technique compared with female skiers. However, the energetic cost of a given power was independent of gender for all modes.