Cramer Joel T, Housh Terry J, Coburn Jared W, Beck Travis W, Johnson Glen O
Department of Health and Exercise Science, University of Oklahoma, Norman, Oklahoma 73019, USA.
J Strength Cond Res. 2006 May;20(2):354-8. doi: 10.1519/R-18105.1.
The purpose of this study was to examine the acute effects of static stretching on peak torque (PT) and the joint angle at PT during maximal, voluntary, eccentric isokinetic muscle actions of the leg extensors at 60 and 180 degrees x s(-1) for the stretched and unstretched limbs in women. Thirteen women (mean age +/- SD = 20.8 +/- 0.8 yr; weight +/- SD = 63.3 +/- 9.5 kg; height +/- SD = 165.9 +/- 7.9 cm) volunteered to perform separate maximal, voluntary, eccentric isokinetic muscle actions of the leg extensors with the dominant and nondominant limbs on a Cybex 6000 dynamometer at 60 and 180 degrees x s(-1). PT (Nm) and the joint angle at PT (degrees) were recorded by the dynamometer software. Following the initial isokinetic assessments, the dominant leg extensors were stretched (mean stretching time +/- SD = 21.2 +/- 2.0 minutes) using 1 unassisted and 3 assisted static stretching exercises. After the stretching (4.3 +/- 1.4 minutes), the isokinetic assessments were repeated. The statistical analyses indicated no changes (p > 0.05) from pre- to poststretching for PT or the joint angle at PT. These results indicated that static stretching did not affect PT or the joint angle at PT of the leg extensors during maximal, voluntary, eccentric isokinetic muscle actions at 60 and 180 degrees x s(-1) in the stretched or unstretched limbs in women. In conjunction with previous studies, these findings suggested that static stretching may affect torque production during concentric, but not eccentric, muscle actions.
本研究的目的是，在女性伸展和未伸展的下肢以60度/秒和180度/秒的速度进行最大自主离心等速肌肉运动时，研究静态拉伸对峰值扭矩（PT）以及PT时关节角度的急性影响。13名女性（平均年龄±标准差=20.8±0.8岁；体重±标准差=63.3±9.5千克；身高±标准差=165.9±7.9厘米）自愿在Cybex 6000测力计上，分别以60度/秒和180度/秒的速度对优势和非优势下肢进行最大自主离心等速肌肉运动。测力计软件记录PT（牛顿米）和PT时的关节角度（度）。在最初的等速评估之后，使用1次无辅助和3次辅助静态拉伸练习对优势腿伸肌进行拉伸（平均拉伸时间±标准差=21.2±2.0分钟）。拉伸后（4.3±1.4分钟），重复进行等速评估。统计分析表明，从拉伸前到拉伸后，PT或PT时的关节角度没有变化（p>0.05）。这些结果表明，在女性伸展或未伸展的下肢以60度/秒和180度/秒的速度进行最大自主离心等速肌肉运动时，静态拉伸不会影响腿伸肌的PT或PT时的关节角度。结合之前的研究，这些发现表明，静态拉伸可能会影响向心肌肉运动期间的扭矩产生，但不会影响离心肌肉运动期间的扭矩产生。
