Abstract：
This study aims to profile biomechanical abilities during sprint front crawl by identifying technical stroke characteristics, in light of performance level. Ninety-one recreational to world-class swimmers equipped with a sacrum-worn IMU performed 25 m all-out. Intra and inter-cyclic 3D kinematical variabilities were clustered using a functional double partition model. Clusters were analysed according to (1) swimming technique using continuous visualisation and discrete features (standard deviation and jerk cost) and (2) performance regarding speed and competition calibre using respectively one-way ANOVA and Chi-squared test as well as Gamma statistics. Swimmers displayed specific technical profiles of intra-cyclic (smoothy and jerky) and inter-cyclic stroke regulation (low, moderate and high repeatability) significantly discriminated by speed (p < 0.001, η2 = 0.62) and performance calibre (p < 0.001, V = 0.53). We showed that combining high levels of both kinds of variability (jerky + low repeatability) are associated with highest speed (1.86 ± 0.12 m/s) and competition calibre (ℽ = 0.75, p < 0.001). It highlights the crucial importance of variabilities combination. Technical skills might be driven by a specific alignment of stroke pattern and its associated dispersion according to the task constraints. This data-driven approach can assist eyes-based technical evaluation. Targeting the development of an explosive swimming style with a high level of body stability should be considered during training of sprinters.
摘要：
这项研究旨在通过识别技术中风特征来描述短跑前爬行过程中的生物力学能力，根据性能水平。91位配备了骶骨磨损的IMU的世界级游泳者的娱乐活动全力以赴25m。使用功能双分区模型对循环内和循环间的3D运动变化进行了聚类。根据（1）使用连续可视化和离散特征（标准偏差和冲击成本）的游泳技术和（2）分别使用单向ANOVA和卡方检验以及Gamma统计量来分析聚类。游泳者显示了周期内（光滑和生涩）和周期间中风调节的特定技术特征（低，中等和高可重复性）通过速度（p<0.001，η2=0.62）和性能口径（p<0.001，V=0.53）显着区分。我们表明，结合高水平的两种变异性（生涩低重复性）与最高速度（1.86±0.12m/s）和竞争口径（=0.75，p<0.001）有关。它强调了变量组合的至关重要性。根据任务约束，可以通过笔划模式及其相关分散的特定对齐来驱动技术技能。这种数据驱动的方法可以帮助基于眼睛的技术评估。在短跑运动员的训练过程中，应考虑发展具有高水平身体稳定性的爆炸性游泳风格。
