Abstract
Cross-country skiing involves frequent single-leg support while coordinating upper and lower body movements and maintaining balance on unstable, gliding surfaces with the assistance of ski poles. Balance and postural control in cross-country skiers have received limited research attention. The objective of this study is to investigate the centre of pressure (COP) and balance strategies in competitive skiers compared to non-skiers in a single-leg stance by measuring COP area and sample entropy (SampEn). Nine varsity-level cross-country skiers (20.67 ± 2.35 years) and nine non-skiers (22.11 ± 1.27 years) were instructed to maintain a quiet stance with eyes open, either on their dominant leg or with feet together, while standing on a force platform. A ski pole was positioned upright beside each participant, who held it lightly during designated conditions. Four conditions were tested: feet together with and without the ski pole, and single-leg stance with and without the pole. Participants completed four 35-second trials per condition, for a total of 16 trials. Preliminary results suggest that standing with the ski pole reduces sway magnitude (lower area and variability) and increases signal regularity across both stances. In single-leg stance without the ski pole, skiers exhibit lower SampEn values than non-skiers, potentially indicating that skiers might be employing more conscious control during challenging balance tasks, resulting in distinct COP dynamics. This distinction diminished when external support was available. Further research could explore whether the conscious control observed in skiers contributes to long-term postural adaptations and increased injury resilience.
