得分状态下竞技跆拳道运动员双飞踢动作下肢生物力学特征分析

目的 探索竞技跆拳道运动员在使用电子护具时双飞踢动作的下肢运动生物力学特征。 方法 利用电子护具计分系统、表面肌电测试设备、三维运动捕捉设备和三维力台,采集 14 名竞技跆拳道运动员双飞踢动作有效得分时下肢关节运动学、动力学和表面肌电数据,使用 Visual 3D 软件计算动作时间、重心位移、下肢关节活动范围和 速度、地面反作用力等参数。 结果 两次击打总用时为 0. 583 s,优势侧和非优势侧的进攻时长一致。 重心偏移较小,优势侧和非优势侧均具有较好的击打平衡控制能力。 两侧下肢关节运动角度和角速度变化的趋势一致;在击打前膝关节屈曲阶段,进攻腿膝关节屈曲角度的不足可以在伸展阶段加大伸展角速度而获得有效击打;在击打前膝关节屈曲和伸展阶段,下肢两侧腓肠肌内侧头募集程度最大。 结论 双飞踢技术具有较好的连续性和左右对称性,在第 2 次击打时减小进攻时间有助于得分。 在双飞踢动作的训练中应加强踝关节灵活性以及腓肠肌、臀大肌的力量训练,避免不必要的运动损伤,以适应穿戴电子护具的比赛模式。

Analysis on Biomechanical Characteristics of Lower Extremities for Athletes under Effective Striking During Double Roundhouse Kick in Competitive Taekwondo

Objective To investigate the biomechanical characteristics of lower extremities of competitive taekwondo athletes during double roundhouse kick ( DRK) with the use of electronic body protector ( EBP). Methods Fourteen competitive taekwondo athletes were recruited, and their kinematic, kinetic and surface electromyogram (sEMG) data of lower limb joints during DRK with effective scoring were collected by electronic guard scoring system, sEMG testing equipment, three-dimensional (3D) motion capture equipment and 3D force plate. The motion time, center of gravity ( COG) displacement, range of motion ( ROM) and velocity of lower limb joints, ground reaction force (GRF) and other parameters were calculated by Visual 3D software. Results The total time for two strikes of DRK was 0. 583 s and the attacking period of both dominant and non-dominant sides was the same. The shift of COG was smaller during the kick, and both dominant and non-dominant sides had good balance control ability. The trends of changes in hip, knee, and ankle joint motion angles and angular velocities of the two limb sides were consistent. In knee flexion phase before striking, the deficiency of knee flexion angle of the attacking leg could be achieved by increasing the extension angular velocity in extension phase. In knee flexion and extension phases before striking, the medial head of the lower extremities gastrocnemius muscle generated the most power on two limb sides. Conclusions The DRK technique has good continuity and left-right symmetry, and it can contribute to scoring by reducing the time of attack during the second striking. Athletes should strengthen the ankle joint flexibility, as well as gastrocnemius and gluteus maximus in training process of DRK movement, so as to avoid unnecessary sports injuries and be more adaptable to game mode with the use of EBP.