目的研究踝关节外固定防护在模拟半蹲式跳伞着陆中对下肢肌电(Electromyogram,EMG)活动性的影响及其性别差异。方法男女各8名健康成人受试者从0.72m高平台跳落,模拟半蹲式跳伞着陆。实验状态分赤足对照、佩戴护踝和绷带3组。测量其胫骨前肌、外侧腓肠肌、股直肌和股二头肌的肌电图。使用二因素方差分析评价防护和性别对EMG参数的影响。结果使用护踝显著增加男性胫骨前肌触地前EMG幅值(赤足对照:266μV;绷带:368μV;护踝:552μV),防护对其他EMG参数无显著性影响。结论使用护踝仅对男性跳伞者有显著的防护作用;踝关节防护对膝关节EMG活动性无显著性影响。
Objective To study effects of ankle stabilizer on electromyographic activities of lower-extremity muscles during the simulated half-squat parachute landing and its gender differences. Method Eight male and eight female healthy adults were required to jump from a platform of 0. 72 m high to simulate half-squat parachute landing. The experiment was divided into 3 groups: the barefoot one as control group,the group wearing tapes and braces respectively. The electromyogram (EMG) of each subject’s tibial anterior,lateral gastrocnemius,biceps femoralis and rectus femoralis was measured. Two-way ANOVA was used to analyze and evaluate the effect of the stabilizers and genders on EMG variables. Results The use of brace significantly increased the pre-landing EMG amplitude of the tibialis anterior for male (Control: 266 μV; Tape: 368 μV; Brace: 552 μV). The stabilizers had no significant effects on the other EMG parameters. Conclusions Semi-rigid ankle braces are capable of arousing more active EMG of male’s ankle flexor during half-squat parachute landing,but female does not share this predominance. Ankle stabilizers have no significant effects on EMG activities for knee joints.