本案例研究研究了世界一流的残奥会游泳运动员的50m自由泳与速度曲线参数之间的关系,并分析了速度曲线及其频率成分在其表现水平上的变化。从2018年到2021年,视力受损的女游泳运动员(50米自由泳26.59秒,S12类)进行了22次测试,以获得与视频记录同步的瞬时速度。她经常在比赛和计时赛中进行50m自由泳。快速傅立叶变换方法将速度信号转换为频域,并确定具有两个最大值和最小值(H2,手臂动作)和六个最大值和最小值(H6,腿部动作)的谐波的相对贡献。功能配对t检验比较了分析周期的开始(PRE)和结束(POST)的速度曲线。50m自由泳时间与平均速度相关(r=-0.50,p=0.02)。H6的贡献在第一年增加,并且仍然很大,而H2的贡献在整个时期都较低。POST在五个时刻比PRE快,这五个时刻与腿部向下踢时刻相吻合。这些变化使她能够在曲线的上部停留更长的时间,并随着时间的推移提高性能。
This
case study examined the association between 50 m
freestyle and speed curve parameters of a world-class Paralympic swimmer and analysed the changes in speed curves and their frequency components across her performance levels. From 2018 to 2021, a visually impaired female swimmer (26.59 s in 50 m
freestyle, S12 class) underwent 22 tests to obtain instantaneous speed synchronised with video recording. She regularly performed 50 m
freestyle in competitions and time trials. The fast Fourier transformation method converted the speed signal into frequency domains and determined the relative contribution of the harmonics with two maxima and minima (H2, arms actions) and six maxima and minima (H6, legs actions). The functional paired t-test compared the speed curves at the beginning (PRE) and end (POST) of the analysed period. The 50 m
freestyle time correlated with average speed (r = -0.50, p = 0.02). The contribution of H6 increased in the first year and remained large, whereas the contribution of H2 was lower throughout the whole period. POST was faster than PRE in five moments that coincide with the downward leg kick moments. These changes allowed her to stay longer at the upper part of the curve and improve performance over time.