滑行技术的革命:速度轮滑双蹬技术的运动生物力学研究

Evolution of Skating Technique:Sports Biomechanical Analysis on Double Push of Inline Speed Roller Skating

采集速度轮滑双蹬技术的运动学与足底受力参数,定量分析其技术动作原理与规律,为高效滑行技术推广与专项训练指导提供科学依据。方法:13名速度轮滑运动员,采用双蹬技术按规定路线以慢速和快速各完成一次直道滑行,2台摄像机分别从侧面和正面拍摄一个完整的复步动作,足底压力分布系统同步采集8 s足底压力数据,提取滑行时间、距离与速度,足底压力的压力时间变化、中心位移变化及足底各区着离地起止时间等参数。结果:随滑行速度的提高,单脚支撑滑行时间变短,平刃滑行时间与路程比例降低,内外刃动力推进时间与路程比例大幅度提高;且各时相的平均速度内刃要高于外刃动力推进阶段,单脚高于双脚支撑阶段。一个单步滑行包括内外刃2次蹬动动作,且外刃蹬动时间长,内刃蹬动时间短。足底压力中心变化幅度单脚大于双脚支撑阶段,内刃大于外刃滑行阶段;滑行速度越快,压力中心变化幅度越小,且前移趋势越明显。结论:速度轮滑双蹬技术一个右单步可分为右平双、右外单、右平单、右内单与右内双5个连续阶段,右脚外刃蹬地有利于保持速度,内刃蹬地是滑速提高的主要动力源,双蹬技术能充分发挥体重蹬地的技术优势,是一种高效的滑行技术。

Objective： The kinematical and mechanical parameters of double push in speed roller skating aresampled to quantitatively analyze its technical theories and rules, which can provide scientific references forspecialized training and the spread of efficient skating techniques. Methods： Two cameras are used to shootacomplete compound step from the front and from the side while skaters, adopting double-push, are slidingstraightway alonga given route once at a fast speed and a slow speed respectively. The sole pressure distributionsystem synchronously samples the sole pressure data for8 seconds, such as sliding time, distance, speed, solepressure variation in time, displacement center variation, and the starting and ending time of landing andtaking-off of various areas of the sole. Results： As the speed goes up, the single-foot support time shortens; theratio of vertical sliding time to the sliding distance lowers; the ratio of inner and outer blade pushes time to thesliding distance rises greatly; in terms of the average speed in various time phases, the inner-blade sliding isfaster than the outer-blade sliding, and the single-foot support sliding is faster than the double-foot supportsliding.A single-step sliding includes an inner-blade push and an outer-blade push, and the time of the formeris shorter than that of the latter. In terms of variation of the sole pressure center, the single-foot support is biggerthan the double-foot support, and the inner-blade push is bigger than the outer-blade push; the faster thesliding is, the smaller the variation of the sole pressure center becomes, and the more obvious the antedisplacement. Conclusion：A right single step of double push in speed roller skating can be divided into fivesuccessive phases： right-vertical-double, right-outer-single, right-vertical-single, right-inner-single andright-inner-double, the right-outer blade push contributes to maintaining the speed, the inner-blade push isthe major source of force for speeding, double push, as a highly efficient sliding technique, allows full play ofbody weight push.