Taniguchi K, Shinohara M, Nozaki S, Katayose M
School of Health Sciences, Sapporo Medical University, Sapporo, Japan.
Scand J Med Sci Sports. 2015 Feb;25(1):32-40. doi: 10.1111/sms.12146. Epub 2013 Dec 2.
The purpose of the study was to examine the acute effect of static stretching exercise on the resting stiffness of gastrocnemius muscle belly. Ten healthy young adults performed standing wall stretching in dorsiflexion for 1 min at a time and repeated five times. Before and after stretching, the shear modulus was measured in medial and lateral heads of the resting gastrocnemius muscle with ultrasound shear-wave elastography. After the stretching, dorsiflexion range of motion (ROM) of the ankle joint increased (P < 0.01) by 3.9° and returned in 20 min. Immediately after stretching, shear modulus decreased (P < 0.01) by 14%, compared with before stretching across muscle heads. The decrease in shear modulus returned in 20 min after stretching. In the comparison group of 10 additional subjects, the standing intervention without stretching had no influence on these measures. There was a negative correlation between dorsiflexion ROM and shear modulus in either head before and after stretching. The results demonstrate the transient decreases in the stiffness of the resting gastrocnemius muscle belly and indicate that joint flexibility is greater in individuals with lower resting stiffness of the muscle belly.
本研究的目的是探讨静态拉伸运动对腓肠肌肌腹静息僵硬度的急性影响。10名健康的年轻成年人每次进行1分钟的站立式墙壁背屈拉伸，重复5次。在拉伸前后，使用超声剪切波弹性成像技术测量静息腓肠肌内侧头和外侧头的剪切模量。拉伸后，踝关节背屈活动范围（ROM）增加了3.9°（P<0.01），并在20分钟后恢复。拉伸后即刻，与拉伸前相比，跨肌头的剪切模量降低了14%（P<0.01）。拉伸后20分钟，剪切模量的降低恢复。在另外10名受试者的对照组中，无拉伸的站立干预对这些指标没有影响。拉伸前后，两个肌头的背屈ROM与剪切模量之间均呈负相关。结果表明，静息状态下腓肠肌肌腹的僵硬度会短暂降低，并且表明肌腹静息僵硬度较低的个体关节灵活性更高。
