Cramer Joel T, Beck Travis W, Housh Terry J, Massey Laurie L, Marek Sarah M, Danglemeier Suzanne, Purkayastha Sushmita, Culbertson Julie Y, Fitz Kristi A, Egan Alison D
Department of Health and Exercise Science, University of Oklahoma, Norman, OK 73019-6081, USA.
J Sports Sci. 2007 Apr;25(6):687-98. doi: 10.1080/02640410600818416.
The aims of this study were to examine the acute effects of static stretching on peak torque, work, the joint angle at peak torque, acceleration time, isokinetic range of motion, mechanomyographic amplitude, and electromyographic amplitude of the rectus femoris during maximal concentric isokinetic leg extensions at 1.04 and 5.23 rad x s(-1) in men and women. Ten women (mean +/- s: age 23.0 +/- 2.9 years, stature 1.61 +/- 0.12 m, mass 63.3 +/- 9.9 kg) and eight men (age 21.4 +/- 3.0 years, stature 1.83 +/- 0.11 m, mass 83.1 +/- 15.2 kg) performed maximal voluntary concentric isokinetic leg extensions at 1.04 and 5.23 rad x s(-1). Following the initial isokinetic tests, the dominant leg extensors were stretched using four static stretching exercises. After the stretching, the isokinetic tests were repeated. Peak torque, acceleration time, and electromyographic amplitude decreased (P< or = 0.05) from pre- to post-stretching at 1.04 and 5.23 rad . s(-1); there were no changes (P > 0.05) in work, joint angle at peak torque, isokinetic range of motion, or mechanomyographic amplitude. These findings indicate no stretching-related changes in the area under the angle - torque curve (work), but a significant decrease in peak torque, which suggests that static stretching may cause a "flattening" of the angle - torque curve that reduces peak strength but allows for greater force production at other joint angles. These findings, in conjunction with the increased limb acceleration rates (decreased acceleration time) observed in the present study, provide tentative support for the hypothesis that static stretching alters the angle - torque relationship and/or sarcomere shortening velocity.
本研究的目的是，在男性和女性以1.04和5.23弧度×秒⁻¹进行最大等速向心腿部伸展运动时，检验静态拉伸对股直肌的峰值扭矩、功、峰值扭矩时的关节角度、加速时间、等速运动范围、肌机械图幅度和肌电图幅度的急性影响。10名女性（平均±标准差：年龄23.0±2.9岁，身高1.61±0.12米，体重63.3±9.9千克）和8名男性（年龄21.4±3.0岁，身高1.83±0.11米，体重83.1±15.2千克）以1.04和5.23弧度×秒⁻¹进行最大自主等速向心腿部伸展运动。在最初的等速测试后，使用四种静态拉伸练习对优势腿伸肌进行拉伸。拉伸后，重复进行等速测试。在1.04和5.23弧度·秒⁻¹时，从拉伸前到拉伸后，峰值扭矩、加速时间和肌电图幅度降低（P≤0.05）；功、峰值扭矩时的关节角度、等速运动范围或肌机械图幅度没有变化（P>0.05）。这些发现表明，角度-扭矩曲线下的面积（功）没有与拉伸相关的变化，但峰值扭矩显著降低，这表明静态拉伸可能会导致角度-扭矩曲线“变平”，从而降低峰值力量，但允许在其他关节角度产生更大的力。这些发现，结合本研究中观察到的肢体加速率增加（加速时间减少），为静态拉伸改变角度-扭矩关系和/或肌小节缩短速度这一假设提供了初步支持。
