不同速度运动状态中竞走运动员下肢动力学特征研究

A Study on the Lower Limb Dynamic Characteristics of Race Walk Athletes among Different Speed Ranges

目的通过对中国竞走学校优秀运动员不同速度运动状态中下肢动力学特征的分析,为优化专项技术动作,减少运动损伤发生,强化竞走后备人才训练及竞技水平提高提供参考依据。方法选取中国竞走学校男、女一级及以上重点运动员各8名。依据目前青少年竞走运动员不同速度区间的划分,应用SONY DSC-RX10M4高速摄像机和Kistler三维测力台同步采集运动员中、高速时下肢的地面反作用力、峰值力和下肢各关节反作用力等动力学数据,应用SIMI运动解析软件和Matlab软件进行计算,采用单因素方差分析对不同速度下的数据进行比较。结果男运动员高速和中速相比,足外侧地面反作用力峰值高速大于中速,且具有显著性差异(P<0.05),足内侧、水平方向和垂直方向的峰值力,均无显著性差异(P>0.05),髋、膝、踝关节水平和垂直方向峰值力均增加,其中髋、膝、踝关节水平方向峰值力增加幅度分别为22.9%、17.5%、20%,垂直方向峰值力增加幅度分别为2.0%、8.2%、2.7%;女运动员高速与中速相比,足外侧和水平前方向地面反作用力峰值高速大于中速,且具有显著性差异(P<0.05),足内侧、水平后和垂直方向峰值力均无显著性差异(P>0.05),髋、膝、踝关节水平和垂直方向峰值力均增加,其中髋、膝、踝关节水平方向峰值力增加幅度分别为31.6%、26.8%、41.7%,垂直方向峰值力增加幅度分别为7.9%、12.8%、7.4%。结论竞走运动员不同速度运动状态下,男、女运动员在一个步态周期中的地面反作用力在不同方向均为高速大于中速,且均表现为垂直方向分力值最大,内外方向的分力最小,而水平方向制动力峰值均大于加速力峰值,此结果为日常训练加强足跟着地动作技术规范性,同时增加蹬地力量训练,提高下肢肌肉用力水平提供了有力证据;另一方面,男、女运动员髋、膝、踝各关节水平和垂直方向峰值力高速均大于中速,在足跟着地时膝关节和踝关节垂直方向受力较大,髋关节受力较小,而前脚掌蹬离地面时,髋部水平方向转动明显大于垂直方向摆动力度,因而青少年竞走运动员日常训练中需加强髋、膝、踝关节运动链的协同和补偿作用,准确掌握竞走技术动作的用力特点和顺序,对于提高其技术动作合理性和科学性,减少下肢损伤,提高运动表现和比赛成绩具有重要意义。

Objective This study aims to explore the effects of ground reaction forces,peak forces,and joint forces on the lower limbs of race walk athletes at different speeds.The results are conducted to optimize athletes'movement techniques,reduce the occurrence of sports injuries,and enhance racewalking performance.Methods Eight male and eight female elite race walk athletes from Chinese racewalking schools,who are at all level the first or above.Kinematic and kinetic data of the lower limbs during medium and high-speed racewalking were synchronously collected using a SONY DSC-RX10M4 highspeed camera and Kistler 3D force platform.The data were processed and analyzed using SIMI motion analysis software and Matlab.Results In comparison between high and medium speeds in male athletes,the peak ground reaction force on the lateral side of the foot was significantly higher at high speed than at medium speed(P<0.05).There were no significant differences in peak forces on the medial side,horizontal and vertical directions(P>0.05).However,peak forces in horizontal and vertical directions at the hip,knee,and ankle joints increased.Specifically,the increase in peak forces in the horizontal direction was 22.9%,17.5%,and 20%for the hip,knee,and ankle,respectively.In the vertical direction,the increases were 2.0%,8.2%,and 2.7%,respectively.For female athletes,the peak ground reaction force on the lateral side of the foot was significantly higher at high speed than at medium speed(P<0.05).There were no significant differences in peak forces on the medial side,foot push-off,and vertical directions(P>0.05).However,peak forces in horizontal and vertical directions at the hip,knee,and ankle joints increased.Specifically,the increase in peak forces in the horizontal direction was 31.6%,26.8%and 41.7%,respectively,and in the vertical direction,the increases were 7.9%,12.8%,and 7.4%,respectively.Conclusion This study investigated the lower limb dynamics of elite race walk athletes in different speed ranges.The findings indicate that,within one gait cycle,the ground reaction force for both male and female athletes exhibited the highest vertical component and the smallest components in the anterior-posterior and medial-lateral directions.Furthermore,the ground reaction forces in different directions were higher at high speed compared to medium speed.In both speed conditions,the peak horizontal braking force was greater than the peak propulsive force,suggesting the importance of maintaining proper foot landing techniques and incorporating push-off strength training to enhance horizontal muscle force exertion in daily training.Additionally,the study revealed that male and female race walk athletes experienced higher peak forces in both horizontal and vertical directions at high speed compared to medium speed,with the increase in horizontal peak forces being significantly greater than in the vertical direction.The results provide solid theoretical guidance for promoting technical optimization and reducing lower limb injuries during the training process for race walk athletes.