Cappozzo A, Felici F, Figura F, Gazzani F
Med Sci Sports Exerc. 1985 Oct;17(5):613-20.
Evaluation of the compressive load acting on the lumbar spine (L3-L4) during half-squat exercises executed with a barbell resting on the subject's shoulders was undertaken. The kinematics of the upper body segments of two male and two female subjects as well as the barbell were described using data obtained by means of an optoelectronic system (CoSTEL). L3-L4 compressive load was calculated using a model of the anatomy of the trunk musculoskeletal system. Filtered surface electromyographic trunk flexor recordings from the obliquus externus and rectus abdominis and trunk extensor erectores spinae muscles as well as measurement of the ground reaction forces were also carried out for predicted result validation. During half-squat exercises with barbell loads in the range 0.8 to 1.6 times body weight the compressive loads on the L3-L4 segment vary between 6 and 10 times body weight. Erectores spinae contraction force was predicted to be between 30 and 50% of the relevant maximal isometric force. The magnitude of trunk flexion was found to be the variable which influenced most spinal compression load.
对在受试者肩部扛着杠铃进行半蹲练习时作用于腰椎（L3 - L4）的压缩负荷进行了评估。使用通过光电系统（CoSTEL）获得的数据描述了两名男性和两名女性受试者以及杠铃的上身节段的运动学。使用躯干肌肉骨骼系统解剖模型计算L3 - L4压缩负荷。还进行了来自腹外斜肌、腹直肌和竖脊肌的滤波后的表面肌电图躯干屈肌记录以及地面反作用力的测量，以验证预测结果。在杠铃负荷为体重的0.8至1.6倍的半蹲练习中，L3 - L4节段上的压缩负荷在体重的6至10倍之间变化。竖脊肌收缩力预计为相关最大等长肌力的30%至50%。发现躯干屈曲程度是影响脊柱压缩负荷最大的变量。
