半蹲式跳伞着陆髋周肌肉激活度生物力学分析

Biomechanical analysis of the muscle activitation on hip joint during half-squat parachute landing

目的通过逆向动力学测定半蹲式跳伞着陆(half-squatparachute landing,HSPL)过程中髋周肌组织的肌肉激活度,研究不同高度和水平距离对髋周肌肉激活度的影响。方法选取22名健康空降兵,受试者分别从40 cm和120 cm 2种高度以半蹲式着陆姿势跳落(120 cm高度增加水平距离80 cm),利用三维运动捕捉系统记录运动数据并导入AnyBody分析软件,建立下肢数据模型。测定髋周五组肌肉的最大肌肉激活度,包括髂腰肌、股直肌、缝匠肌、股二头肌、臀大肌。结果不同高度:随着高度增加,5组肌肉激活度增加,差异具有统计学意义(P<0.05)。2种高度下,髂腰肌、股直肌和缝匠肌峰值较高。臀大肌的激活度始终维持在15%,其曲线较为平缓,波动幅度小。不同水平距离比较:随着水平距离增加,5组肌肉激活度增加,差异具有统计学意义(P<0.05)。不同水平距离时髋周肌肉激活度曲线中5组肌肉都具有2个波峰,髂腰肌、缝匠肌的波峰最大。120-80 cm臀大肌幅度波动较大,而在120-0 cm并未出现。结论髂腰肌、股直肌是髋部受力缓冲的主要肌肉,缝匠肌、股二头肌、臀大肌维持冠状位的髋部稳定。水平距离可增加关节屈曲度,使髋部损伤的风险增加。

Objective To investigate the effect of dropping height and horizontal distance on muscle activation of hips during half-suat parachute landing(HSPL)using inverse dynamic software.Methods Twenty-two male paratroopers paticipating in routine landing training were selected.The subjects jumped from platforms of two different heights(40 cm and 120 cm)and two different horizontal distances(0 and 80 cm).The motion data was recorded by the Vicon motion capture system and the experimental data was input into the AnyBody Modeling System.Reverse dynamic analysis was conducted to calculate the activation of five muscles:illopsoas muscle activation(IMA),rectus femoris activation(RFA),sartorius muscle activation(SMA),biceps femoris activation(BFA),and gluteus maximus activation(GMA).Results Two different heights:with an increase in dropping height,the activation of five muscles(IMA,RFA,SMA,BFA,GMA)inceased with statistically significant difference(P<0.05).The peaks of IMA,RFA and SMA were larger under two heights.The gluteus maximus activation still averaged 15%.The curve of gluteus maximus,smooth and lower,fluctuated within a small range.Two different horizontal distances:The activation of the five muscles increased with the horizontal distance,and there was significant difference(P<0.05).Each of the muscles had two peaks in the curve under two different distances.The peaks of IMA and RFA were larger than those of the other three muscles.GMA fluctuated significantly in the 120-80 cm curve but not in the 120-0 cm curve.Conclusion The IM and RF play importent roles in cushion protection during HSPL.The SM,BF,GM can maintain coronal balance of hips.The horizontal distance can lead to intensified muscle activity of hips,increasing the incidence of hip muscle injury and fracture.