Abstract
Cross-country skiers frequently perform movements requiring single-leg stability, making postural control a cornerstone of their performance. Their sport-specific demands involve balancing on sliding surfaces while coordinating complex upper and lower body movements using ski poles. Despite its importance, postural control in cross-country skiing remains unexplored. This study aimed to examine muscle activation in dual- and single-leg stance tasks in varsity-level cross-country skiers, and to assess how ski pole support influences neuromuscular control. We hypothesized that skiers would display reduced muscular activation due to better postural control. Nine varsity skiers (20.67 ± 2.35 years) and nine non-skiers (22.11 ± 1.27 years) were recruited. Participants stood either feet together or on their dominant leg, with or without a ski pole on their non-dominant side. Each condition included four 35-second trials performed with eyes open. Tibialis anterior (TA) and medial gastrocnemius (MG) muscle activity were recorded using surface electromyography (EMG), rectified, and smoothed via RMS envelope. Signals were normalized to the maximal voluntary isometric contraction. Mean EMG and co-contraction index (CCI) were calculated. Across all conditions, ski pole support reduced TA, MG, and CCI activation (p < 0.05), suggesting a generalized unloading effect. During single-leg stance, skiers showed lower TA and CCI activation than non-skiers, suggesting more efficient control. However, these group differences disappeared when the pole was used. These findings reveal neuromuscular differences between cross-country skiers and non-skiers during challenging balance tasks. Such information may be useful for guiding training and rehabilitation strategies in cross-country skiers.
