Marshall Paul W, Lovell Ric, Siegler Jason C
School of Science and Health, University of Western Sydney, Penrith South, NSW, Australia.
Int J Sports Physiol Perform. 2016 Jul;11(5):594-601. doi: 10.1123/ijspp.2015-0009. Epub 2015 Oct 9.
Passive muscle tension is increased after damaging eccentric exercise. Hamstring-strain injury is associated with damaging eccentric muscle actions, but no research has examined changes in hamstring passive muscle tension throughout a simulated sport activity. The authors measured hamstring passive tension throughout a 90-min simulated soccer match (SAFT90), including the warm-up period and every 15 min throughout the 90-min simulation.
Passive hamstring tension of 15 amateur male soccer players was measured using the instrumented straight-leg-raise test. Absolute torque (Nm) and slope (Nm/°) of the recorded torque-angular position curve were used for data analysis, in addition to total leg range of motion (ROM). Players performed a 15-min prematch warm-up, then performed the SAFT90 including a 15-min halftime rest period.
Reductions in passive stiffness of 20-50° of passive hip flexion of 22.1-29.2% (P < .05) were observed after the warm-up period. During the SAFT90, passive tension increased in the latter 20% of the range of motion of 10.1-10.9% (P < .05) concomitant to a 4.5% increase in total hamstring ROM (P = .0009).
The findings of this study imply that hamstring passive tension is reduced after an active warm-up that includes dynamic stretching but does not increase in a pattern suggestive of eccentric induced muscle damage during soccer-specific intermittent exercise. Hamstring ROM and passive tension increases are best explained by improved stretch tolerance.
在进行造成损伤的离心运动后，被动肌肉张力会增加。腘绳肌拉伤与造成损伤的离心肌肉动作有关，但尚无研究考察在模拟体育活动中腘绳肌被动肌肉张力的变化情况。作者在一场90分钟的模拟足球比赛（SAFT90）全程，包括热身期以及90分钟模拟过程中的每15分钟，测量了腘绳肌的被动张力。
使用仪器化直腿抬高试验测量15名男性业余足球运动员的腘绳肌被动张力。除了全腿活动范围（ROM）外，记录的扭矩 - 角度位置曲线的绝对扭矩（Nm）和斜率（Nm/°）用于数据分析。球员们进行了15分钟的赛前热身，然后进行SAFT90，其中包括15分钟的中场休息时间。
在热身期后，观察到被动髋关节屈曲20 - 50°时的被动刚度降低了22.1 - 29.2%（P <.05）。在SAFT90期间，在活动范围的后20%内，被动张力增加了10.1 - 10.9%（P <.05），同时腘绳肌总ROM增加了4.5%（P =.0009）。
本研究结果表明，在包括动态拉伸的主动热身之后，腘绳肌被动张力会降低，但在足球特定间歇性运动期间，其增加模式并不表明存在离心诱导的肌肉损伤。腘绳肌ROM和被动张力的增加最好用拉伸耐受性的提高来解释。
