Alhammoud Marine, Trama Robin, Hautier Christophe André, Girard Olivier, Racinais Sébastien, Hansen Clint, Meyer Frédéric, Farooq Abdulaziz, Coint Jérémy, Trameau Thibaut, Brun Loïc, Morel Baptiste
Inter-University Laboratory of Human Movement Biology, Universite Claude Bernard Lyon 1, Villeurbanne, France.
Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.
Exp Physiol. 2024 Sep 5. doi: 10.1113/EP091743.
This case study aims to examine changes in the lower limb joint kinematic profile and performance stability induced by repeated ski runs in two world-class alpine skiers. Two Olympic medallist alpine skiers were tested during their slalom training, with continuous recording of right knee and hip angles, along with turn time and run time. The eight runs of the training session were analysed with linear mixed models. Results showed no effect of runs repetition on performance (i.e., run and turn time; P ≥ 0.279). There was no global effect of runs repetition on minimal and maximal angles for either the knee or the hip (P > 0.151). There was an interaction between run and leg for the maximal angle of both the knee and hip (P ≤ 0.047), which increased across runs for the outside leg and decreased for the inside leg. The maximal angular velocity for both the knee and hip increased with runs repetition in extension (P ≤ 0.028). There were no overall changes in maximal angular velocity in flexion with runs repetition (P ≥ 0.264), but there was an interaction between run and leg for the knee (P < 0.001) due to faster eccentric velocities across runs for the outside leg and slower velocities for the inside leg. In conclusion, the observed joint kinematic alterations without concomitant performance impairment support the concept of multiple movement strategies in athletes to achieve similar performance, especially under fatigue conditions.
本案例研究旨在考察两次世界级高山滑雪运动员重复滑雪滑行对下肢关节运动学特征及表现稳定性的影响。两名奥运会高山滑雪奖牌获得者在进行回转滑雪训练时接受测试，持续记录右膝和髋关节角度，以及转弯时间和滑行时间。采用线性混合模型对训练课的八次滑行进行分析。结果显示，滑行重复次数对表现（即滑行和转弯时间；P≥0.279）没有影响。滑行重复次数对膝关节或髋关节的最小和最大角度均无总体影响（P>0.151）。膝关节和髋关节的最大角度在滑行与腿之间存在交互作用（P≤0.047），外侧腿的该角度随滑行次数增加，内侧腿的则减小。膝关节和髋关节在伸展时的最大角速度随滑行重复次数增加（P≤0.028）。滑行重复次数对屈曲时的最大角速度无总体变化（P≥0.264），但膝关节在滑行与腿之间存在交互作用（P<0.001），原因是外侧腿在各次滑行中的离心速度更快，内侧腿的速度较慢。总之，观察到的关节运动学改变而无相应的表现受损支持了运动员采用多种运动策略以实现相似表现的概念，尤其是在疲劳状态下。
