Bouvier Tom, Opplert Jules, Cometti Carole, Babault Nicolas
National Institute for Health and Medical Research (INSERM), Unit 1093, Cognition, Action and Sensorimotor Plasticity, BP 27877, 21078, Dijon Cedex, France.
Centre for Performance and Expertise, Sport Science Faculty, Université de Bourgogne, BP 27877, 21078, Dijon Cedex, France.
Eur J Appl Physiol. 2017 Jul;117(7):1309-1315. doi: 10.1007/s00421-017-3618-9. Epub 2017 Apr 25.
This study aimed to determine the acute effects of static stretching on stiffness indexes of two muscle groups with a contrasting difference in muscle-tendon proportion.
Eleven active males were tested on an isokinetic dynamometer during four sessions randomly presented. Two sessions were dedicated to quadriceps and the two others to triceps surae muscles. Before and immediately after the stretching procedure (5 × 30 s), gastrocnemius medialis and rectus femoris fascicle length and myotendinous junction elongation were determined using ultrasonography. Passive and maximal voluntary torques were measured. Fascicle and myotendinous junction stiffness indexes were calculated.
After stretching, maximal voluntary torque similarly decreased for both muscle groups. Passive torque significantly decreased on triceps surae and remained unchanged on quadriceps muscles. Fascicle length increased similarly for both muscles. However, myotendinous junction elongation remained unchanged for gastrocnemius medialis and increased significantly for rectus femoris muscle. Fascicle stiffness index significantly decreased on medial gastrocnemius and remained unchanged on rectus femoris muscle. In contrast, myotendinous junction stiffness index similarly decreased on both muscles.
Depending on the muscle considered, the present results revealed different acute stretching effects. This muscle dependency appeared to affect primarily fascicle stiffness index rather than the myotendinous junction.
本研究旨在确定静态拉伸对肌腱比例存在显著差异的两组肌肉刚度指标的急性影响。
11名活跃男性在等速测力计上进行测试，共进行4次测试，测试顺序随机安排。其中两次测试针对股四头肌，另外两次针对小腿三头肌。在拉伸程序（5×30秒）之前和之后立即使用超声测量腓肠肌内侧头和股直肌的肌束长度和肌腱结合部伸长情况。测量被动和最大自主扭矩。计算肌束和肌腱结合部的刚度指标。
拉伸后，两组肌肉的最大自主扭矩均同样降低。小腿三头肌的被动扭矩显著降低，而股四头肌的被动扭矩保持不变。两组肌肉的肌束长度均同样增加。然而，腓肠肌内侧头的肌腱结合部伸长保持不变，而股直肌的肌腱结合部伸长显著增加。腓肠肌内侧头的肌束刚度指标显著降低，股直肌的肌束刚度指标保持不变。相比之下，两组肌肉的肌腱结合部刚度指标均同样降低。
根据所研究的肌肉不同，本研究结果显示了不同的急性拉伸效果。这种肌肉依赖性似乎主要影响肌束刚度指标，而非肌腱结合部。
