Grabiner M D, Jeziorowski J J
Department of Musculoskeletal Research, Research Institute, The Cleveland Clinic Foundation, Cleveland, Ohio, USA.
Clin Biomech (Bristol). 1991 May;6(2):118-22. doi: 10.1016/0268-0033(91)90009-F.
This study examined the relationship between sagittal plane isokinetic trunk extension and flexion strength and endurance using three isokinetic velocities (60, 120, and 180° s(-1)). Healthy male subjects with no history of low back problems performed 25 consecutive repetitions of a 100° trunk extension-flexion task with encouragement to execute each repetition with maximum effort. Between each isokinetic velocity, 5 min of rest were provided. The traditional isokinetic variables of peak torque and work for trunk extension and flexion were extracted from the torque-position curves and fatigue profiles were generated with linear regression using the mean values of peak torque and work from repetitions 2-4, 7-9, 12-14, 17-19 and 22-24. The linear regression analysis defined the relationship between fatigue and the number of repetitions. The rate of fatigue (given by the slope of the regression equation) and the magnitude of the fatigue was maximum in the 60° condition. The fatigue rate and the magnitude were both related to the absolute strength given by the maximum work output. The trunk flexors were observed to be more susceptible to fatigue than the trunk extensors.
本研究使用三种等速速度（60、120和180°/秒），考察矢状面等速躯干伸展与屈曲力量及耐力之间的关系。无腰痛病史的健康男性受试者进行了100°躯干伸展-屈曲任务的连续25次重复动作，并鼓励其每次重复动作都尽最大努力完成。在每个等速速度之间，给予5分钟休息时间。从扭矩-位置曲线中提取躯干伸展和屈曲的传统等速变量，即峰值扭矩和功，并使用第2-4次、7-9次、12-14次、17-19次和22-24次重复动作的峰值扭矩和功的平均值，通过线性回归生成疲劳曲线。线性回归分析确定了疲劳与重复次数之间的关系。在60°条件下，疲劳率（由回归方程的斜率给出）和疲劳程度最大。疲劳率和疲劳程度均与最大功输出所表示的绝对力量有关。观察到躯干屈肌比躯干伸肌更容易疲劳。
