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Acute Effects of Static versus Dynamic Stretching on Isometric Peak Torque, Electromyography, and Mechanomyography of the Biceps Femoris Muscle

Authors:
Trent Herda at University of Kansas
Trent Herda
Joel Cramer at University of Central Florida
Joel Cramer
Eric D Ryan
Eric D Ryan
Eric D Ryan
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Malachy P McHugh at Nicholas Institute of Sports Medicine and Athletic Trauma Lenox Hill Hospital
Malachy P McHugh
  • Nicholas Institute of Sports Medicine and Athletic Trauma Lenox Hill Hospital
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Abstract

The purpose of this study was to examine the acute effects of static versus dynamic stretching on peak torque (PT) and electromyographic (EMG), and mechanomyographic (MMG) amplitude of the biceps femoris muscle (BF) during isometric maximal voluntary contractions of the leg flexors at four different knee joint angles. Fourteen men ((mean +/- SD) age, 25 +/- 4 years) performed two isometric leg flexion maximal voluntary contractions at knee joint angles of 41 degrees , 61 degrees , 81 degrees , and 101 degrees below full leg extension. EMG (muV) and MMG (m x s(-2)) signals were recorded from the BF muscle while PT values (Nm) were sampled from an isokinetic dynamometer. The right hamstrings were stretched with either static (stretching time, 9.2 +/- 0.4 minutes) or dynamic (9.1 +/- 0.3 minutes) stretching exercises. Four repetitions of three static stretching exercises were held for 30 seconds each, whereas four sets of three dynamic stretching exercises were performed (12-15 repetitions) with each set lasting 30 seconds. PT decreased after the static stretching at 81 degrees (p = 0.019) and 101 degrees (p = 0.001) but not at other angles. PT did not change (p > 0.05) after the dynamic stretching. EMG amplitude remained unchanged after the static stretching (p > 0.05) but increased after the dynamic stretching at 101 degrees (p < 0.001) and 81 degrees (p < 0.001). MMG amplitude increased in response to the static stretching at 101 degrees (p = 0.003), whereas the dynamic stretching increased MMG amplitude at all joint angles (p </= 0.05). These results suggested that the decreases in strength after the static stretching may have been the result of mechanical rather than neural mechanisms for the BF muscle. Overall, an acute bout of dynamic stretching may be less detrimental to muscle strength than static stretching for the hamstrings.
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ACUTE EFFECTS OF STATIC VERSUS DYNAMIC STRETCHING ON ISOMETRIC PEAK TORQUE, E...
Trent J Herda; Joel T Cramer; Eric D Ryan; Malachy P McHugh; Jeffrey R Stout
Journal of Strength and Conditioning Research; May 2008; 22, 3; ProQuest Medical Library
pg. 809
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
... Stretching techniques before physical activity are common practices aimed at increasing the flexibility of athletes, and static and dynamic stretching are the most common techniques used toward this goal. 1 Scientific evidence have shown that static stretching may temporarily reduce force and power. 2,3 The acute reduction in force has been termed the "stretching-induced force deficit," and it may be harmful to athletic performance. 4 Although the precise mechanism is unknown, research data have suggested that the stretching-induced force deficit could be caused by (a) neural factors (decrease in motor unit activation, firing frequency, and reflex inhibition from afferent types III and IV) that reduce muscle activation, (b) mechanical factors (changes in the viscoelastic properties of the musculotendinous unit or changes in the angle-torque relationship) that affect the transmittal of force, or a combination of factors. ...
... 4 Although the precise mechanism is unknown, research data have suggested that the stretching-induced force deficit could be caused by (a) neural factors (decrease in motor unit activation, firing frequency, and reflex inhibition from afferent types III and IV) that reduce muscle activation, (b) mechanical factors (changes in the viscoelastic properties of the musculotendinous unit or changes in the angle-torque relationship) that affect the transmittal of force, or a combination of factors. 3,5 Hypotheses attempting to explain the deleterious effects of acute stretching include reduced stiffness of the musculotendinous unit, resulting in less effective transfer of force from the muscle to the lever and greater autogenic inhibition and, therefore, fewer motor units activated in a stretched muscle. 6 Studies indicate that stretching-induced performance changes were typically low to moderate in magnitude when testing was performed immediately after the stretching protocol. ...
... Herda et al 3 have shown that 4 sets of 3 dynamic stretches of 30 s each increased EMG and mechanomyogram activity. 3 Also, Fletcher and Monte-Colombo 17 indicated that 100-beat dynamic stretching resulted in significantly greater countermovement jump and drop jump heights than 50-beat dynamic stretching. Even 50-beat dynamic stretching showed significantly greater performance in the jumps than the no-stretch condition. ...
Acute Effect of Static and Dynamic Stretching on Activating Scapular Stabilizer Muscles During Pull-Up Movement in Gymnasts
Article
  • May 2024
Background and Aims Today, there is an argument about the effect of various stretching movements on the performance of athletes. Therefore, this study investigated the acute effect of static and dynamic stretching on muscle activity and co-contraction of scapular stabilizer muscles during pull-ups in gymnasts. Methods According to the inclusion and exclusion criteria, 15 professional gymnasts with a mean age of 23.25±2.57 years, height of 170.93±5.88 cm, and weight of 64.54±5.06 kg were selected as research samples and divided into three subgroups (each with 5 athletes). In the pre-test, subjects performed pull-up activity, and muscle activities of the serratus anterior, upper trapezius, middle trapezius, and lower trapezius muscles were measured using a biometric electromyography device. Then, each subgroup performed a different stretching protocol in each session, and a post-test was conducted like the pre-test. Repeated measures analysis of variance, the Bonferroni post hoc test, and the paired t test were used to test the study hypotheses. Results The results showed that static and dynamic stretching caused a significant decrease and increase in muscle activity in both concentric and eccentric phases, respectively. Also, the results showed that dynamic stretch caused a reduction in co-contraction of the serratus anterior and middle trapezius muscles in both concentric and eccentric phases. In addition, there is a significant difference between the effect of static and dynamic stretch and between dynamic stretch and control on the co-contraction of the serratus anterior and middle trapezius muscles in the concentric and eccentric phases. Conclusion The results showed that the co-contraction of the serratus anterior and middle trapezius muscles decreased after using dynamic stretching. Therefore, considering the importance of muscle co-contraction in the occurrence of shoulder joint injuries and preventing injuries in the shoulder joint of gymnasts, it is suggested that coaches and gymnasts use dynamic stretching exercises more carefully.
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... DS which involve controlled movement through the active range of motion for each joint (Fletcher, 2010) is currently replacing static stretching in warm-up (Behm & Chaouachi, 2011). It has been reported that DS performed before exercise increases heart late (Fletcher, 2010;Fletcher & Monte-Colombo, 2010a) and core temperature (Fletcher & Jones, 2004;Fletcher & Monte-Colombo, 2010b), induces post-activation potentiation in the stretched muscle caused by voluntary contractions of the antagonist (Hough et al., 2009;Torres et al., 2008), and increases activation of motor units (Fletcher, 2010;Herda et al., 2008). Previous studies have shown that such DS associated factors improve vertical jump (Kurt et al., 2023;Meerits et al., 2014;Smith et al., 2018) and sprint (Lopez-Samanes et al., 2021;Malek et al., 2024) performance, and leg extension power (Yamaguchi et al., 2007). ...
... On the other hand, in the FULL | 2025 | ISSUE 5 | VOLUME 20 © 2025 ARD Asociación Española condition, in which DS was performed before and between sets of exercise, the vertical jump performance was significantly higher in the latter half of the sets compared to the other conditions. Factors that may have contributed to the effects of DS on subsequent performance improvement include increased heart rate (Fletcher, 2010;Fletcher & Monte-Colombo, 2010a) and core temperature (Fletcher & Jones, 2004;Fletcher & Monte-Colombo, 2010b), post-activation potentiation in the stretched muscle caused by voluntary contractions of the antagonist (Hough et al., 2009;Torres et al., 2008), and increased activation of motor units (Fletcher, 2010;Herda et al., 2008). The increased heart rate caused by DS may affect blood flow and core temperature, which in turn may cause an increase in sensitivity of nerve receptors and speed of nerve impulses, therefore enabling muscle contraction to be more rapid and forceful (Fletcher & Monte-Colombo, 2010a). ...
The effects of dynamic stretching performed before and between the sets of exercises on vertical jump performance
Article
Full-text available
  • Dec 2024
The purpose of this study was to investigate the effects of dynamic stretching (DS) performed before and between the sets of exercises on vertical jump performance. Twelve healthy adult males performed DS on their lower limb muscles, with 10 repetitions on each side before and between four sets of three repetitions of vertical jumps. Vertical jump height was measured. Additionally, the percent change in jump height for each set was determined based on the baseline score from set 1. Heart rate was also measured at rest, before exercise, and before each set of vertical jumps. Vertical jump height was significantly higher in the latter half of the sets (p < .05) compared to the condition in which DS was only performed before exercise and to the control condition in which the participants were refrained from performing DS throughout. In addition, when DS was only performed before exercise, vertical jump height was significantly lower in set 4 compared to set 1 (p = .001). These findings suggest that DS performed between sets, in addition to performing before the exercise, produces a higher power output in vertical jump performance in the latter half of multiple sets.
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... Despite its use for qualitatively assessing motor unit recruitment and firing rate modulation, the sMMG signal is often analyzed using traditional amplitude-and frequency-based methods that focus on static characteristics, overlooking its dynamic changes over time. For instance, while the Fast-Fourier Transform provides a detailed frequency spectrum of the sMMG signal [15], analyses often reduce this information to summary measures like mean or median frequency, which may obscure the nuanced evolution of frequency components during exercise [3,[16][17][18]. To further our understanding of the etiology of any shifts in the frequency components of a signal, time-frequency signal processing techniques such as wavelet transform have been previously proposed [15,19]. ...
... Most of the previous literature investigating sMMG responses of the superficial quadriceps muscle has typically focused on a single parameter, such as mean amplitude or frequency [3,[16][17][18]. However, the frequency component of the sMMG signal is inherently multifaceted, comprising multiple frequencies that represent diverse physiological inputs, including contributions from motor units across a spectrum of activation thresholds [1,2,15]. ...
Examination of Sex-Related Differences in Fatigability and Frequency Components of Mechanomyographic Signals During Sustained Exercise
Article
Full-text available
  • Dec 2024
Background: Surface mechanomyographic (sMMG) signals have been used to examine sex-specific differences in the mechanical behavior of muscle during fatiguing exercise. However, studies often utilize simple amplitude- and frequency-based analyses, which only reveal the static components of the sMMG signal. Methods: Thus, a wavelet-based analysis was used to examine changes in the spectral intensity of the non-dominant limb’s vastus lateralis during a fatiguing, maximal, unilateral isometric leg extension in recreationally active men (n = 11) and women (n = 10). Relative changes in spectral intensities and instantaneous mean frequency (IMF) were examined using linear mixed-effect models. Time-to-task failure was compared using an independent sample t-test. Results: The neuromuscular responses demonstrated parallel decreases in IMF (p < 0.001). Further, there were parallel, nonlinear, decreases in spectral intensity across wavelets (p < 0.001) and there were no sex differences in time-to-task failure (p = 0.15). Conclusions: These data showed no sex-specific differences in exercise fatigability or muscle mechanics during fatiguing exercise of the leg extensors. However, when collapsed across sex, wavelet-specific changes in spectral intensity over time reveal novel insights into the interplay between low- and high-frequency components during fatigue.
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... The lack of CMJ height decrease after DS has often been observed [33,42,43]. This contrasting effect as compared to SS or CRAC is generally attributed to three likely mechanisms, including increased temperature [44], more sport-specific movements [45], and altered central drive [28]. ...
Acute Effects of Short Static, Dynamic, and Contract–Relax with Antagonist Contraction Stretch Modalities on Vertical Jump Height and Flexibility
Article
Full-text available
  • Apr 2025
The present study investigated the acute effects of different stretching modalities applied within a warm-up on flexibility and vertical jump height. Thirty-seven young adults participated in four randomized experimental sessions, each corresponding to a different condition: static stretch (SS), dynamic stretch (DS), contract–relax with antagonist contraction (CRAC) or a control condition with no stretch (CTRL). Conditions were five min in total duration, including 2 × 15 s stretches for each muscle group (knee flexor, knee extensor, and plantar flexor muscles). Ten min and five min of cycling preceded and followed these procedures, respectively. Hamstring flexibility and a series of countermovement jump (CMJ) measurements were interspersed within this procedure. Except for CTRL, hamstring flexibility significantly increased (p < 0.01) after all experimental procedures (7.5 ± 6.6%, 4.1 ± 4.9%, and 2.7 ± 6.0% for CRA, SS, and DS, respectively). The relative increase was significantly greater for CRAC as compared CTRL (p < 0.001). Vertical jump height significantly decreased (p < 0.05) immediately after SS (−2.3 ± 3.9%), CTRL (−2.3 ± 3.5%), and CRAC (−3.2 ± 3.3%). Jump height was unchanged after DS (0.4 ± 4.5%). Whatever the condition, no additional jump height alteration was obtained after the re-warm-up. The main findings of the present study revealed that DS is more appropriate for maintaining vertical jump height. However, stretching has no major effect when performed within a warm-up. In contrast, if the main objective is to increase flexibility, CRAC is recommended.
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... Specifically, engaging in static stretching for an extended duration, exceeding 60 seconds, has been observed to elicit stretch-induced strength performance deficits during subsequent resistance training sessions [16]. The underlying mechanisms responsible for this phenomenon are multifaceted and intricate, encompassing alterations in tendon stiffness and perturbations in the force-length relationship [17], as well as stretch-induced contractile damage to muscle fibers and a subsequent reduction in electromechanical coupling efficiency [18]. ...
Effects of Muscle Stretching on Muscle Flexibility and Strength: A Literature Review
Article
Full-text available
  • Feb 2025
For numerous years, stretching has been a widely employed technique across various sports disciplines. One of the primary factors influencing the effect on range of motion post-stretching is muscle-tendon stiffness (MTS). Recently, researchers have made groundbreaking discoveries, revealing that stretching can significantly enhance movement range by effectively decreasing MTS. While traditional static stretching has been a staple in warm-up routines, it also appears to adversely impact exercisers' strength performance, raising concerns among athletes and coaches alike. In response to these findings, various studies have introduced alternative stretching forms such as dynamic stretching and proprioceptive neuromuscular facilitation (PNF) stretching, alongside long-term training programs. These innovative approaches aim to optimize the beneficial effects of stretching while mitigating its detrimental outcomes on strength and performance. To comprehensively understand and delineate the immediate and prolonged impacts of both static and dynamic stretching, along with the efficacy of different stretching protocols, this study meticulously examined recent research articles. The objective of this review is to propose a clear terminology and methodology for stretching practices, thereby providing guidance for exercise training and physical activities. By doing so, it seeks to enhance the efficiency and scientific rigor of stretching protocols, ensuring that athletes and fitness enthusiasts can reap the maximum benefits from their stretching routines.
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... However, previous research has demonstrated the negative effects of static stretching of the agonist muscles on strength and power production Cramer et al., 2005;Jeffreys, 2008). Some of the studies revealed that prolonged static stretching decreased muscle activation (Cramer et al., 2005;Ryan et al., 2014) while others found no significant change in muscle activation but suggested that the loss of strength resulted from altered mechanical factors of the muscle (Herda et al., 2008;Sandberg et al., 2012). The negative impact of static stretching on muscle contraction raises the question of whether antagonist static stretching could contribute to agonist performance; reducing antagonist cocontraction theoretically enhances agonist power output potential by requiring less work to perform the same task (Ford et al., 2008). ...
Effects of Static Stretching of Antagonist Muscles on Lower Extremity Power Output in Elite Female Volleyball Players
Article
Full-text available
  • Dec 2024
Aim: This study aimed to investigate the effect of antagonist static stretching on lower-body peak power output in elite volleyball players. Methods: Twenty-one elite female volleyball players (age: 23.95±5.04 years, height: 181.90±7.54 cm, mass: 70.96±8.38 kg) were randomly divided into two groups: 1) antagonist static stretching group and 2) dynamic stretching group. After implementing the stretching protocols, peak power output was assessed by performing loaded squat jumps using three different loads: 20%, 40%, and 60% of one-repetition maximum. Forty-eight hours later, on the second testing day, participants in the dynamic stretching group and antagonist static stretching group switched groups and underwent the same procedure. Results: Peak power output obtained at 20% of one repetition maximum in dynamic stretching group was significantly greater than the peak power output at the same load in the antagonist static stretching group (p<0,05); no significant difference was found at the other equal loads between stretching groups (p>0,05). Peak power output values at three different exercise loads within each group were analyzed: in dynamic stretching group, peak power output was significantly greater at 20% compared to 60% of one repetition maximum (p<0,05), and at 40% compared to 60% of one repetition maximum (p<0,05). In antagonist static stretching group, peak power output was significantly greater at 20% compared to 60% of one repetition maximum (p<0,05), and at 40% compared to 60% of the one repetition maximum (p<0,05). Conclusion: Antagonist static stretching did not produce any beneficial effects in elite female volleyball players when compared to dynamic stretching.
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... Secondly, DS exerts stimulatory effects on the nervous system (Jaggers J. R. et al., 2008). Studies have demonstrated that DS increases electromyographic amplitude, indicating greater muscle activation and neuromuscular efficiency (Herda et al., 2008). This heightened activation is crucial for improving neuromuscular coordination and responsiveness, which are essential components of enhanced balance performance. ...
Neuromuscular and balance adaptations following acute stretching exercise: a randomized control trial
Article
Full-text available
  • Dec 2024
Purpose This study aimed to examine the acute effects of static stretching (SS) and dynamic stretching (DS) on neuromuscular function and balance in recreationally active men. Method Sixty participants were randomly assigned to SS, DS, or no stretching (NS) groups. Before and after their respective stretching protocols, participants were assessed using the stork balance test (SBT), Y-balance test (YBT), T-change of direction test (CoD T-test), countermovement jump test (CMJT), squat jump test (SJT), and five-time jump test (FJT). Results Significant main effects of time were observed for the SBT, YBT, and CoD T-test. Significant interactions between time and group were found for the SBT, YBT, CoD T-test, and CMJT (P < 0.05). Compared to the NS group, the SS group showed significant improvement in the SBT (P < 0.05), while the DS group demonstrated significant improvements in the SBT, YBT (all directions), CoD T-test, CMJT, and SJT (P < 0.05). Post-training, the DS group showed greater improvements than the SS group in the YBT, CoD T-test, CMJT, and SJT (P < 0.05), with no significant differences in the SBT. Conclusion SS acutely improves static balance, while DS has a broader impact, enhancing both neuromuscular function and balance.
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... As a result, research on both types of stretching has rapidly increased, particularly with studies of specific elements of athletic performance, including force, power, and sprinting speed. [14] A novel technique called flossing tissue -using a floss band device -has been devised to improve the ROM and flexibility. The Voodoo Floss Band, a 7' × 2" band, is a recently introduced tool in the clinical setting. ...
Immediate effect of dynamic stretching with and without floss band on hamstring flexibility in futsal players: A pilot study
Article
  • Nov 2024
Objectives The objective of this study was to assess the immediate impact of dynamic stretching with and without floss band on hamstring flexibility in futsal players. Methods Fifty-four players were included and randomly divided into tissue flossing and non-tissue flossing groups. Both groups performed dynamic stretching of the hamstring muscle, three sets of 15 repetitions. Active knee extension (AKE), straight leg raise (SLR), and sit-and-reach tests were conducted before and after the intervention. Blood samples were also drawn pre- and post-intervention to determine serum creatine kinase (CK) and lactate dehydrogenase (LDH) for recording muscle damage. Results On comparing the results of both groups, the tissue flossing group had significantly increased scores (left leg P = 0.005, right leg P = 0.007) for the AKE and sit-and-reach tests ( P = 0.017). The two groups had no significant SLR, CK, or LDH disparity ( P > 0.05). On the other hand, within-group comparisons showed a significant disparity ( P < 0.05) between all variables in both groups. Conclusion The present study revealed that dynamic stretching with and without a floss band improved hamstring flexibility by increasing AKE, SLR, and sit-and-reach tests; however, results were significantly improved with a floss band. Compared to dynamic stretching without flossing, flossing resulted in better improvement of AKE and sit-and-reach test scores, while serum CK and LDH remained the same for both groups.
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FARKLI EGZERSİZLER İLE OLUŞTURULAN POST AKTİVASYON POTANSİYASYONUNUN YÖN DEĞİŞTİRME PERFORMANSINA ETKİLERİNİN KARŞILAŞTIRILMASI 2024 YÜKSEK LİSANS TEZİ BEDEN EĞİTİMİ VE SPOR
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Acoustic Myography: Applications and Considerations in Measuring Muscle Performance
Article
  • Jan 1993
Acoustic myography (AMG) is the technique of recording muscle sounds and is potentially useful as an indicator of force. This review provides a background of the history, basic physical principles, and methodology of recording muscle sounds. Some obvious limitations of the technique are addressed, but others need to be investigated. Guidelines for the appropriate use and potential applications of AMG are discussed. Use of the AMG technique in the clinical situation would be premature at this early stage of its development.
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Gender, muscle, and velocity comparisons of mechanomyographic and electromyographic responses during isokinetic muscle actions
Article
  • Apr 2004
The purpose of this study was to examine the responses of peak torque (PT), mean power output (MP), mechanomyographic (MMG) and electromyographic (EMG) amplitude and mean power frequency (MPF) of the vastus lateralis (VL), rectus femoris (RF), and vastus medialis (VM) in males and females during maximal, concentric isokinetic muscle actions. Subjects performed maximal leg extensions at 60degrees s(-1), 120degrees s(-1), 180degrees s(-1), 240degrees s(-1), 300degrees s(-1), 360degrees s(-1), 420degrees s(-1), and 480degrees s(-1). No gender differences were obser-ved, but there were muscle-specific differences for the patterns of MMG MPF, EMG amplitude, and EMG MPF. The MP and MMG amplitude increased to 180-240degrees s(-1), plateaued, and then decreased to 480degrees s(-1). MMG MPF for the VL and VM remained unchanged to 300degrees s(-1), but then increased to 480degrees s(-1). The EMG amplitude for the RF and EMG MPF for the VL decreased across velocity. Overall, these findings indicated that there were muscle-specific, velocity-related differences in the associations among motor control strategies (EMG amplitude and MPF) and the mechanical aspects of isokinetic muscular activity (MMG amplitude and MPF).
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Developing a Stretching Program
Article
  • Nov 1981
Although stretching exercises can prevent muscle injuries and enhance athletic performance, they can also cause injury. The author explains the four most common types of stretching exercises and explains why he considers static stretching the safest. He also sets up a stretching routine for runners. In setting up a safe stretching program, one should precede stretching exercises with a mild warm-up; use static stretching; stretch before and after a workout; begin with mild and proceed to moderate exercises; alternate exercises for muscle groups; stretch gently and slowly until tightness, not pain, is felt; and hold the position for 30 to 60 seconds.
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Acute Static Stretching Reduces Lower Extremity Power in Trained Children
Article
  • May 2003
  • PEDIATR EXERC SCI
Several studies utilizing adult subjects have indicated that static stretching may reduce subsequent strength and power production, possibly for as long as an hour following the stretch. This observation has not been evaluated in children, nor in athletes accustomed to performing static stretches during strength/ power type training sessions. The purpose of this investigation was to determine if an acute bout of passive, static stretching of the lower extremity would affect jumping performance in a group of young, female gymnasts. Thirteen competitive gymnasts (age 13.3 ± 2.6 yrs) performed drop jumps under two conditions: immediately following stretching and without prior stretching. The jumps were performed on separate days. The conditions were randomly ordered among the subjects. Time in the air (AIR) and ground contact time (CT) were measured during the drop jumps using a timing mat. Three different stretches of the lower extremity were conducted on each gymnast twice, each stretch being held for 30 seconds. Following the stretching condition, AIR was significantly reduced (.44 vs .46 sec, p < .001), while CT was not different (.130 for both conditions, p > .05). This study demonstrates that children's lower extremity power is reduced when the performance immediately follows passive, static stretching, even in children accustomed to static stretching during training sessions involving explosive power.
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