Effect of participants' static stretching knowledge or deception on the responses to prolonged stretching.
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.
School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, NL A1C 5S7, Canada.|School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, NL A1C 5S7, Canada.
W C Ian
WC
Janes
School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, NL A1C 5S7, Canada.|School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, NL A1C 5S7, Canada.
Brandon B G
BB
Snow
School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, NL A1C 5S7, Canada.|School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, NL A1C 5S7, Canada.
Caisie E
CE
Watkins
School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, NL A1C 5S7, Canada.|School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, NL A1C 5S7, Canada.
Elecia A L
EA
Noseworthy
School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, NL A1C 5S7, Canada.|School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, NL A1C 5S7, Canada.
Jonathan C
JC
Reid
School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, NL A1C 5S7, Canada.|School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, NL A1C 5S7, Canada.
David G
DG
Behm
D000293:Adolescent; D000328:Adult; D000070379:Attentional Bias; D003142:Communication; D008192:Deception; D000070633:Hamstring Muscles / Q000502:physiology*; D007722:Health Knowledge, Attitudes, Practice; D006801:Humans; D008297:Male; D053580:Muscle Strength; D052580:Muscle Stretching Exercises / Q000009:adverse effects*; D063806:Myalgia / Q000209:etiology* / Q000517:prevention & control; D010349:Patient Compliance; D010353:Patient Education as Topic; D010827:Physiology / Q000193:education; D052097:Quadriceps Muscle / Q000502:physiology*; D057566:Self Report; D013997:Time Factors; D055815:Young Adult
force; hamstrings; ischio-jambiers; placebo; rate of force development; taux de production de la force