400米跑下肢主要肌群表面肌电的变化研究

Surface Electromyographic Variations in Major Lower Limb Muscle Groups during a 400-Meter Race

目的:评定400m跑过程中下肢双侧主要肌群表面肌电的变化。方法:21名健康男性受试者,于左、右下肢选定肌肉肌腹处粘贴电极片,采集400m跑过程中的肌电信号。测试场地为400m环形跑道,统一先迈右腿,绕跑道尽力跑一圈。结果:与400m跑前期下肢骨骼肌的平均振幅相比,中期右胫骨前肌的平均振幅下降极其显著(P≤0.001),左腓肠肌外侧、左胫骨前肌、右股外侧肌的平均振幅显著下降(P<0.05);后期左腓肠肌外侧、右股二头肌内侧、右股直肌、右股外侧肌的平均振幅显著下降(P<0.05)。中期与后期相比,后期左胫骨前肌的平均振幅显著上升、右股直肌的平均振幅显著下降(P<0.05)。与400m跑前期下肢骨骼肌的积分肌电值相比,中期左腓肠肌外侧的积分肌电值显著下降(P<0.05);后期右股直肌的积分肌电值显著下降(P<0.05)。中期与后期相比,后期左胫骨前肌的积分肌电值显著上升、右股二头肌内侧、右股直肌的积分肌电值显著下降(P<0.05)。与400m跑前期下肢骨骼肌的峰值肌电相比,后期左胫骨前肌的峰值肌电下降极其显著(P=0.001);右股二头肌内侧的峰值肌电显著下降、右胫骨前肌的峰值肌电显著上升(P<0.05)。中期与后期相比,后期左胫骨前肌的峰值肌电下降极其显著(P<0.001),右胫骨前肌的峰值肌电显著上升(P<0.05)。左股二头肌内侧、左胫骨前肌、右股二头肌内侧、右腓肠肌外侧、右胫骨前肌的中值频率下降极其显著(P≤0.001),左股直肌、左股内侧肌、右股外侧肌中值频率显著下降(P<0.05)。结论:整体上,研究表明400m跑所选择的6块肌群表面肌电存在差异化的变化,上述发生改变的肌群可能潜在影响400m跑的运动成绩,对股二头肌,胫骨前肌等在400m跑过程中肌电显著下降的肌肉应采取针对性的训练。

OBJECTIVE:To evaluate surface electromyographic changes in major lower limb muscle groups during a 400-meter race.METHODS:21 healthy male subjects had electrodes attached to muscle bellies in the left and right lower limbs,capturing electromyographic signals during a 400-meter race on a circular track.RESULTS:Compared to the early phase of the 400-meter race,the mid-phase exhibited a significant reduction in the average amplitude of the right tibialis anterior muscle(P<0.001),along with significant decreases in the average amplitude of the lateral gastrocnemius,left tibialis anterior,and right vastus lateralis muscles(P<0.05).In the late phase,there were notable decreases in the average amplitude of the lateral gastrocnemius,right rectus femoris,right vastus lateralis,and right gastrocnemius muscles(P<0.05).When comparing mid-phase to late-phase,there was a significant increase in the average amplitude of the left tibialis anterior muscle and a significant decrease in the average amplitude of the right rectus femoris muscle(P<0.05).Regarding integrated electromyographic values,the mid-phase showed a significant decrease in the integrated electromyographic value of the lateral gastrocnemius(P<0.05),and the late phase exhibited significant decreases in the integrated electromyographic value of the right rectus femoris(P<0.05).When comparing mid-phase to late-phase,there was a significant increase in the integrated electromyographic value of the left tibialis anterior muscle and significant decreases in the integrated electromyographic values of the right rectus femoris and right vastus lateralis muscles(P<0.05).In comparison to the early phase,the late phase displayed an extremely significant decrease in the peak electromyographic value of the left tibialis anterior muscle(P=0.001),along with significant decreases in the peak electromyographic values of the right rectus femoris and significant increases in the peak electromyographic value of the right tibialis anterior muscle(P<0.05).When comparing mid-phase to late-phase,there was an extremely significant decrease in the peak electromyographic value of the left tibialis anterior muscle(P<0.001)and a significant increase in the peak electromyographic value of the right tibialis anterior muscle(P<0.05).The median frequency of the left rectus femoris,left tibialis anterior,right rectus femoris,right lateral gastrocnemius,and right tibialis anterior muscles exhibited an extremely significant decrease(P<0.001),while the median frequency of the left rectus femoris,left adductor magnus,and right vastus lateralis muscles showed a significant decrease(P<0.05).CONCLUSION:Overall,the study indicates distinctive changes in surface electromyography among six selected muscle groups during a 400-meter race.The altered muscle groups may potentilly impact 400-meter race performance,suggesting targeted training for muscles with significant electromyographic decreases,such as the rectus femoris and tibialis anterior muscles.