Huang Ruifeng, Ma Yong, Lin Shijie, Zheng Weitao, Liu Lin, Jia Mengyao
Engineering Research Center of Sports Health Intelligent Equipment of Hubei Province, Wuhan Sports University, Wuhan, China.
Research Center of Sports Equipment Engineering Technology of Hubei Province, Wuhan Sports University, Wuhan, China.
Front Bioeng Biotechnol. 2024 Oct 9;12:1449073. doi: 10.3389/fbioe.2024.1449073. eCollection 2024.
To explore the biomechanical factors affecting the stability of athletes in the 143D balance phase of competitive Tai Chi.
The Vicon 3D motion capture system, Kistler 3D force platform, and Noraxon surface electromyography (sEMG) system were used to measure the joint angle, joint moment, center of gravity, ground reaction force, and sEMG data of athletes. The stability index was then calculated according to the formula. Pearson's or Spearman's correlation tests were used to analyze the associations between the biomechanical factors and stability index.
(1) Medial lateral stability index (MLSI): A significant negative correlation was found between the ankle inversion angle of the supporting leg (SL) and MLSI ( < 0.05). (2) Anterior posterior stability index (APSI): Significant negative correlations were observed between the ankle intorsion angle, integrated electromyography (iEMG) of the gastrocnemius, and muscle contribution rates of the tibialis anterior, external oblique, and gastrocnemius of the non-supporting leg (NL) with the APSI ( < 0.05). The ankle dorsiflexion moment, iEMG of the rectus femoris and tibialis anterior, muscle contribution rate of the biceps femoris, and root mean-squared (RMS) amplitude of the gluteus maximus of the SL also showed significant negative correlations with the APSI ( < 0.05). Strong and significant negative correlations were also identified between the hip intorsion angle, iEMG of the tibialis anterior, and RMS amplitude of the rectus femoris of the NL with the APSI ( < 0.01). Further strong and significant negative correlation was also found between the RMS amplitude of the biceps femoris of the SL and APSI ( < 0.01). The knee extorsion angle of the NL was positively correlated with the APSI ( < 0.05). (3) Dynamic postural stability index (DPSI): The knee adduction angle, iEMG of the tibialis anterior, and RMS amplitude of the erector spinae of the NL were significantly positively correlated with the DPSI ( < 0.05). The knee abduction and hip extension moments of the SL were also significantly positively correlated with the DPSI ( < 0.05).
The ankle inversion angle of the SL impacts left-right stability, while the NL's hip and ankle intorsion angles, knee extorsion angle, and exertion on the core muscle and SL's main muscles, as well as exertion of specific muscles of the NL affect anterior-posterior stability. The hip extension and knee abduction moments of the SL, knee adduction angle, exertion on the tibialis anterior, and activation of the erector spinae of the NL significantly affect the overall stability of an athlete.
探讨影响竞技太极拳143D平衡阶段运动员稳定性的生物力学因素。
使用Vicon 3D运动捕捉系统、Kistler 3D力平台和Noraxon表面肌电图（sEMG）系统测量运动员的关节角度、关节力矩、重心、地面反作用力和sEMG数据。然后根据公式计算稳定性指数。采用Pearson或Spearman相关性检验分析生物力学因素与稳定性指数之间的关联。
（1）内外侧稳定性指数（MLSI）：支撑腿（SL）的踝关节内翻角度与MLSI之间存在显著负相关（<0.05）。（2）前后稳定性指数（APSI）：非支撑腿（NL）的踝关节内旋角度、腓肠肌积分肌电图（iEMG）以及胫骨前肌、腹外斜肌和腓肠肌的肌肉贡献率与APSI之间存在显著负相关（<0.05）。支撑腿的踝关节背屈力矩、股直肌和胫骨前肌的iEMG、股二头肌的肌肉贡献率以及臀大肌的均方根（RMS）振幅与APSI也存在显著负相关（<0.05）。非支撑腿的髋关节内旋角度、胫骨前肌的iEMG以及股直肌的RMS振幅与APSI之间也存在强且显著的负相关（<0.01）。支撑腿股二头肌的RMS振幅与APSI之间还存在进一步的强且显著的负相关（<0.01）。非支撑腿的膝关节外旋角度与APSI呈正相关（<0.05）。（3）动态姿势稳定性指数（DPSI）：非支撑腿的膝关节内收角度、胫骨前肌的iEMG以及竖脊肌的RMS振幅与DPSI显著正相关（<0.05）。支撑腿的膝关节外展和髋关节伸展力矩与DPSI也显著正相关（<0.05）。
支撑腿的踝关节内翻角度影响左右稳定性，而非支撑腿的髋关节和踝关节内旋角度、膝关节外旋角度以及核心肌肉和支撑腿主要肌肉的发力，以及非支撑腿特定肌肉的发力影响前后稳定性。支撑腿的髋关节伸展和膝关节外展力矩、非支撑腿的膝关节内收角度、胫骨前肌的发力以及竖脊肌的激活显著影响运动员的整体稳定性。
