Janes W C Ian, Snow Brandon B G, Watkins Caisie E, Noseworthy Elecia A L, Reid Jonathan C, Behm David G
School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, NL A1C 5S7, Canada.
Appl Physiol Nutr Metab. 2016 Oct;41(10):1052-1056. doi: 10.1139/apnm-2016-0241. Epub 2016 Jun 14.
Much of the static stretching (SS) literature reports performance impairments with prolonged SS. However, it has been acknowledged that a limitation of these studies is participants' knowledge or bias. Since many participants have knowledge of the literature, their performance may be subconsciously influenced by expectations. Hence, the objective of this study was to examine the effect of stretching knowledge or deception on subsequent force output following SS. Two groups of male participants who were either aware (BIASED: 14) or unaware (DECEPTION: 14) of the SS literature participated. Unaware participants were misinformed that SS increases force production. Testing involved maximal voluntary isometric contractions (MVC) of the quadriceps and hamstrings at pre-, post-, and 5 min post-intervention (three 30-s passive hamstring stretches to the point of discomfort with 30-s rest intervals) or control. While the DECEPTION group displayed impaired knee flexion force (p = 0.04; 3.6% and 10.4%) following hamstrings SS, there was no significant impairment with the BIASED (-1.1% and +0.9%) group. Both groups exhibited hamstrings F200 (force produced in the first 200 ms) impairments following SS. Whereas BIASED participants exhibited an overall decrease (p < 0.05; 1.8% and 4.2%) in knee extension MVC, DECEPTION participants showed (p = 0.005; 8.8% and 5.1%) force increases. The quadriceps F200 was not significantly affected with the BIASED group but overall there were 4.5% and 8.7% F200 impairments at 1 and 5 min post-intervention (p = 0.05) with the DECEPTION group. Thus while deception resulted in enhanced quadriceps muscle force output, there was no knowledge or deception advantage when stretching the hamstrings.
许多关于静态拉伸（SS）的文献报道，长时间的静态拉伸会导致运动表现下降。然而，人们已经认识到，这些研究的一个局限性在于参与者的认知或偏差。由于许多参与者了解相关文献，他们的表现可能会受到潜意识中期望的影响。因此，本研究的目的是探讨拉伸知识或欺骗对静态拉伸后后续力量输出的影响。两组男性参与者参与了实验，一组知晓静态拉伸文献（有偏差组：14人），另一组不知情（欺骗组：14人）。不知情的参与者被错误告知静态拉伸会增加力量产生。测试包括在干预前、干预后以及干预后5分钟时对股四头肌和腘绳肌进行最大自主等长收缩（MVC）（对腘绳肌进行三次30秒的被动拉伸至不适程度，每次拉伸间隔30秒休息）或进行对照测试。虽然欺骗组在腘绳肌静态拉伸后膝关节屈曲力量受损（p = 0.04；分别下降3.6%和10.4%），但有偏差组没有显著受损（分别下降-1.1%和上升+0.9%）。两组在静态拉伸后腘绳肌的F200（前200毫秒产生的力量）均受损。有偏差组的参与者膝关节伸展MVC总体下降（p < 0.05；分别下降1.8%和4.2%），而欺骗组的参与者力量增加（p = 0.005；分别增加8.8%和5.1%）。有偏差组的股四头肌F200没有受到显著影响，但欺骗组在干预后1分钟和5分钟时F200总体受损4.5%和8.7%（p =
