Static Stretching Research Articles

Duration-Dependent Effects of Passive Static Stretching on Musculotendinous Stiffness and Maximal and Rapid Torque and Surface Electromyography Characteristics of the Hamstrings.

Palmer, TB, Pineda, JG, Cruz, MR, and Agu-Udemba, CC. Duration-dependent effects of passive static stretching on musculotendinous stiffness and maximal and rapid torque and surface electromyography characteristics of the hamstrings. J Strength Cond Res 33(3): 717-726, 2019-This study aimed to examine the effects of stretching duration on passive musculotendinous stiffness and maximal and rapid torque and surface electromyography (EMG) characteristics of the hamstrings. Thirteen young females (age = 21 ± 2 years) underwent 2 passive straight-leg raise (SLR) assessments and 2 isometric maximal voluntary contractions (MVCs) of the hamstrings before and after 4 randomized conditions that included a control treatment and 3 experimental treatments of passive static stretching for 30-, 60-, and 120-second durations. Passive stiffness was calculated during each SLR as the slope of the final 10% of the angle-torque curve. Isometric peak torque (PT), rate of torque development (RTD), peak EMG amplitude (PEMG), and rate of EMG rise (RER) were extracted from each MVC. Results indicated that PT and PEMG were not affected (p = 0.993 and 0.422, respectively) by any of the experimental treatments. Rate of torque development and RER decreased from pre- to post-treatment for 120 seconds (p = 0.001 and 0.001) but not for the control (p = 0.616 and 0.466), 30- (p = 0.628 and 0.612), and 60-second (p = 0.396 and 0.815) interventions. The slope coefficient decreased from pre- to post-treatment for the 30- (p = 0.001), 60- (p = 0.002), and 120-second (p = 0.001) stretching interventions but not for the control (p = 0.649). Given the significant stiffness reductions and lack of changes in PT and RTD for the 30- and 60-second interventions, it may be advantageous for practitioners who are using hamstring passive stretching as part of a warm-up routine, to perform such stretching on their clients for short (30-60 seconds) rather than moderate (120-second) stretching durations.

Effects of Static Stretching and Foam Rolling on Ankle Dorsiflexion Range of Motion.

Participants (n = 44) were randomly assigned to FR, SS, and FR + SS groups. The FR group foam rolled the triceps surae. The SS group performed a wall stretch for both legs. The FR + SS group performed FR immediately followed by SS. All groups completed 12 training sessions in 6 wk. Dorsiflexion ROM was assessed before and after the first training session, before the second session of week 3, before and after the last session in week 6, and at week 7. There was a 4.0% acute increase in ROM at week 6 (P = 0.004) for all three groups. ROM increased 8.4% from week 3 to week 7 for all three groups (P < 0.001). When comparing week 1 baseline to week 7, ROM increased 18.3% for all three groups (P = 0.003). SS and FR seem to be comparable in terms of increasing dorsiflexion ROM acutely as well as after 6 wk of training for healthy, university-age participants. FR combined with SS does not seem to provide a synergistic effect on improving dorsiflexion ROM.

The Effect of Static Stretching of Peroneal and Tibialis Anterior Muscles on Reaction Time: A Randomized Controlled Study.

The aim of this study was to investigate the acute and chronic effects of static stretching on peroneal and tibialis anterior reaction characteristics. All 23 participants who volunteered for this study were randomly divided into static (n = 12) and control (n = 11) groups. The subjects in the static stretching group performed stretching exercises for the ankle evertor and dorsiflexor muscles 5 days a week for 6 wks. Peroneal and tibialis anterior muscle reaction characteristics were evaluated at the beginning (2 times for acute effect) and end of this period. Electromyographic activity parameters of the muscles were measured using an ankle inversion tilting platform that simulated a sudden ankle inversion. The following were the four different ankle inversion conditions: (a) ankle-neutral, 15-degree inversion; (b) ankle-neutral, 30-degree inversion; (c) ankle-20-degree plantarflexion, 15-degree inversion; and (d) ankle-20-degree plantarflexion, 30-degree inversion. Either in terms of acute or chronic effects, no significant differences were found after static stretching exercises for peroneal and tibialis anterior muscle reaction time, reaction duration, and muscle activity evaluated in four positions on the ankle inversion simulation platform (P > 0.05). In light of these results, it is possible to state that the short duration of static stretching exercises can still be applied before sports activities.

Proteins and Signaling Pathways Response to Dry Needling Combined with Static Stretching Treatment for Chronic Myofascial Pain in a RAT Model: An Explorative Proteomic Study.

A quantitative proteomic analysis of the response to dry needling combined with static stretching treatment was performed in a rat model of active myofascial trigger points (MTrPs). 36 rats were divided into a model group (MG), a stretching group (SG) and a dry needling combined with stretching group (SDG). We performed three biological replicates to compare large-scale differential protein expression between groups by tandem mass tag (TMT) labeling technology based on nanoscale liquid chromatography mass spectrometry analysis (LC–MS/MS). Hierarchical clustering, Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment and protein-protein interaction network analyses were performed for the general characterization of overall enriched proteins. For validation of the results of TMT, the candidate proteins were verified by parallel reaction monitoring (PRM) analysis. 285 differentially expressed proteins between groups were identified and quantified. Tight junction pathway played a dominant role in dry needling combined with static stretching treatment for the rat model of active MTrPs. Three candidate proteins, namely actinin alpha 3, calsequestrin-1 and parvalbumin alpha, were further validated, consistent with the results of LC–MS/MS. This is the first proteomics-based study to report the therapeutic mechanism underlying dry needling and static stretching treatment for MTrPs. Further functional verification of the potential signaling pathways and the enriched proteins is warranted.

Chronic Effects of a Static Stretching Program on Hamstring Strength.

Nakao, S, Ikezoe, T, Nakamura, M, Umegaki, H, Fujita, K, Umehara, J, Kobayashi, T, Ibuki, S, and Ichihashi, N. Chronic effects of a static stretching program on hamstring strength. J Strength Cond Res 35(7): 1924-1929, 2021-This study investigated the effects of a 4-week static stretching (SS) program on isokinetic and isometric knee flexor peak torque and angle of peak torque. Thirty healthy men (age, 22.7 ± 2.2 years) were randomized to receive either of the following: (a) a 4-week stretch intervention for the hamstrings (SS intervention group; n = 15) or (b) no intervention (control group; n = 15). The maximum pain-free knee angle, passive stiffness, which was determined by a slope of torque-angle curve, isometric and isokinetic (at 60°·s-1 and 180°·s-1) peak torque, and angle of peak torque for knee flexors were measured before and after 4 weeks. After 4 weeks, passive stiffness decreased significantly in the intervention group. There were no significant changes in isometric and isokinetic (neither at 60°·s-1 nor at 180°·s-1) peak torque, or angle of peak torque at 180°·s-1. A significantly increased peak extension angle at 60°·s-1 was observed in the intervention group. These results suggest that SS intervention is effective for decreasing musculotendinous unit stiffness of the hamstrings and that an SS program influences the angle of peak torque, whereas no significant changes occur in peak torque. Because a previous study suggests that angle of peak torque is associated with hamstring strain injuries, the results of this study would be helpful when considering the training program for preventing or treating hamstring strain injuries.

Acute Effects of Intermittent Versus Continuous Bilateral Ankle Plantar Flexor Static Stretching on Postural Sway and Plantar Pressures: A Randomized Clinical Trial.

Background: Postural balance and fall efficacy (self-perceived confidence in performing daily physical activities) have been found to be risk factors associated with falls in older adults. Stretching is one intervention that has been investigated to improve balance and therefore reduce fall risk. Various forms of stretching have been evaluated with different outcomes, but there is a lack of knowledge about the effect of stretching (continuous and intermittent) on plantar pressures and balance. Therefore, the aim of the present study was to analyze the effects of stretching (continuous and intermittent) of the bilateral ankle plantar flexors on plantar pressures and static balance. Methods: A randomized clinical trial was carried out. Forty-eight healthy subjects (42 females and 6 males) were recruited in an outpatient clinic. Subjects were randomly assigned to an intermittent stretching group (five sets of 1 min; 15 s of rest) or a continuous stretching group (2 min of continuous stretching) of the plantar flexors. Plantar pressures and balance using stabilometry were measured before and after stretching. Results: There were significant differences between intermittent and continuous stretching in rearfoot maximum pressure, forefoot surface area, and center of pressure surface area with eyes open. Conclusions: Bilateral intermittent stretching of the ankle plantar flexors was found to be more effective than continuous stretching for the reduction of rearfoot maximum pressure and improved balance.

Does the combination of resistance training and stretching increase cardiac overload?

OBJECTIVES:To compare the effects of combinations of resistance training (RT) and static stretching (SS) on heart rate (HR), systolic pressure (SBP), diastolic pressure (DBP), rate pressure product (RPP), oxygen saturation (SpO2), rating of perceived effort (RPE), and heart rate variability (HRV) in men.METHODS:Twelve normotensive healthy men participated in four protocols: a) SS+RT, b) RT+SS, c) RT, and d) SS. Variables were measured before, immediately after, and 15, 30, and 45 min after the sessions.RESULTS:The combination of SS and RT increased (p<0.001) HR when compared to the effects of the noncombined protocols (from 2.38 to 11.02%), and this result indicated metabolic compensation. Regarding DBP, there were differences (p<0.001) between the RT and SS groups (53.93±8.59 vs. 67.00±7.01 mmHg). SS has been shown to be able to reduce (p<0.001) SpO2 (4.67%) due to the occlusion caused by a reduction in the caliber of the blood vessels during SS compared to during rest. The increase in RPP (6.88% between RT and SS+RT) along with the HR results indicated higher metabolic stress than that reflected by the RPE (combined protocols increased RPE from 21.63 to 43.25%). The HRV analysis confirmed these results, showing increases (p<0.01) in the LF index between the combined and noncombined protocols. Compared to the effect of RT, the combination of SS and RT promoted a vagal suppression root mean square of the successive differences (RMSSD) index (from 9.51 to 21.52%) between the RT and SS+RT groups (p<0.01) and between the RT and RT+SS groups (p<0.001).CONCLUSION:Static stretching increases cardiac overload and RPE, reducing oxygen supply, especially when performed in combination with RT.

Effectiveness of Self Myofascial Release, Static Stretching and Neural Tissue Mobilization on Hamstring Flexibility in Athletes

Context: Day by day, sports participation in youth is increasing. Due to increased participation, exercise related injuries are increased. Repeated Exercises causes microtrauma leading to fibrous tissue adhesions which further leads to decreased flexibility ultimately leading to Musculoskeletal dysfunctions. Aim: To study the effectiveness of Self Myofascial Release, Static Stretching and Neural Tissue Mobilization on Hamstring flexibility in athletes Methodology: 80 subjects of the age group 18-25 were randomly allocated to receive Self Myofascial Release and Static Stretching (Group A) and Neural Tissue Mobilization (Group B). Group A was given 3 sets of Foam Rolling for 30 to 60 seconds combined with 3 sets of static stretching for 20 to 30 seconds hold. Each subject was assessed for Active Knee Extension and Straight Leg Raise at baseline and immediately post-treatment. Results: Both the interventions significantly improved AKE and SLR immediately post treatment within the groups whereas the inter group analysis showed significant difference in AKE between Groups but no significant difference was found in SLR. Conclusion: Self Myofascial Release combined with Static Stretching and Neural Tissue Mobilization both were effective in improving Hamstring Flexibility, but Neural Tissue Mobilization was found to be superior.

Intermittent but Not Continuous Static Stretching Improves Subsequent Vertical Jump Performance in Flexibility-Trained Athletes.

Bogdanis, GC, Donti, O, Tsolakis, C, Smilios, I, and Bishop, DJ. Intermittent but not continuous static stretching improves subsequent vertical jump performance in flexibility-trained athletes. J Strength Cond Res 33(1): 203-210, 2019-This study examined changes in countermovement jump (CMJ) height after an intermittent or a continuous static stretching protocol of equal total duration. Sixteen male, elite-level gymnasts performed 90 seconds of intermittent (3 × 30 seconds with 30 seconds rest) or continuous stretching (90 seconds) of the quadriceps muscle. A single-leg stretching and jumping design was used, with the contralateral limb serving as a control. The same individuals performed both conditions with alternate legs in a randomized, counterbalanced order. One-leg CMJ height was measured for the stretched and the control leg after warm-up, immediately after stretching, and at regular intervals for 10 minutes after stretching. Range of motion (ROM) of the hip and knee joints was measured before, after, and 10 minutes poststretching. Compared with the control leg, intermittent stretching increased CMJ height by 8.1 ± 2.0%, 4 minutes into recovery (2.2 ± 2.0 cm, 95% confidence interval [CI]: 1.0-3.4 cm, p = 0.001), whereas continuous stretching decreased CMJ height by 17.5 ± 3.3% immediately after (-2.9 ± 1.7 cm, 95% CI: -2.0 to -3.7 cm, p = 0.001) and by 12.0 ± 2.7% 1 minute after stretching (-2.2 ± 2.1 cm, 95% CI: -1.2 to -3.2 cm, p = 0.001). The increases in hip (2.9 and 3.6°, p = 0.001. d = 2.4) and knee joint ROM (5.1 and 6.1°, p = 0.001. d = 0.85) after the intermittent and continuous stretching protocols were not different. The opposite effects of intermittent vs. continuous stretching on subsequent CMJ performance suggests that stretching mode is an important variable when examining the acute effects of static stretching on performance in flexibility-trained athletes.

A Survey of Static and Dynamic Stretching Protocol

A Survey of Static and Dynamic Stretching Protocol

Effect of Simultaneously Conducting Static Stretching and Therapeutic Ultrasound on the Gastrocnemius Muscle

Effect of Simultaneously Conducting Static Stretching and Therapeutic Ultrasound on the Gastrocnemius Muscle

Tissue-Level Mechanosensitivity: Predicting and Controlling the Orientation of 3D Vascular Networks.

Understanding the mechanosensitivity of tissues is a fundamentally important problem having far-reaching implications for tissue engineering. Here we study vascular networks formed by a coculture of fibroblasts and endothelial cells embedded in three-dimensional biomaterials experiencing external, physiologically relevant forces. We show that cyclic stretching of the biomaterial orients the newly formed network perpendicular to the stretching direction, independent of the geometric aspect ratio of the biomaterial's sample. A two-dimensional theory explains this observation in terms of the network's stored elastic energy if the cell-embedded biomaterial features a vanishing effective Poisson's ratio, which we directly verify. We further show that under a static stretch, vascular networks orient parallel to the stretching direction due to force-induced anisotropy of the biomaterial polymer network. Finally, static stretching followed by cyclic stretching reveals a competition between the two mechanosensitive mechanisms. These results demonstrate tissue-level mechanosensitivity and constitute an important step toward developing enhanced tissue repair capabilities using well-oriented vascular networks.

Agility performance variation from morning to evening: dynamic stretching warm-up impacts performance and its diurnal amplitude

ABSTRACTThis study aimed to assess the effects of different types of stretching on the diurnal variations of the agility performance. Twenty elite young soccer players (age: 17.40 ± 0.94 years) completed the T-test agility, either after static stretching (SS), dynamic stretching (DS), and no-stretching (NS) protocols at two times of the day (morning: 07:00 h-8:30 and evening: 17:00–18:30h), with a minimum of 2 days between testing sessions. The DS group produced significantly faster times on the agility test (9.65 ± 0.05s) in comparison to both the SS group (9.88 ± 0.042s, p< 0.01) and NS group (9.80±0.046s, p<0.01), in the morning. In addition, differences between groups revealed significant difference in the evening with a better result produced after DS (9.37 ± 0.052s in comparison to both SS group(9.70 ± 0.49s (p<0.01) and NS group (9.69 ± 0.43s, p < 0.010).The improvement of performance after (DS) compared to (NS) was significantly faster in the evening than the morning with a greater improvement at 17:00 h compared to 7:00 h (4.26 ± 2.81%vs1.78 ± 0.65%; p<0.01). Results support the use of DS affects the typical diurnal variations of agility performance either in the morning or in the evening and helps to counteract the physiological decrease in morning value.

Acute Effect of Active and Passive Static Stretching on Elastic Modulus of the Hamstrings.

The purpose of this study was to investigate differences in the acute effects of passive knee extension (PKE) and active knee extension (AKE) stretching on the shear elastic modulus of the hamstrings. In 20 healthy men, maximum knee extension (maximum range of motion [ROM]) and shear elastic modulus of the hamstrings (biceps femoris long head, semitendinosus, semimembranosus) were measured before (Pre) and after (Post) AKE and PKE stretching. The maximum ROM during stretching was measured. In both stretching methods, maximum ROM increased and the shear elastic modulus decreased (p<0.01), but no difference was found between the procedures. No significant difference was observed in the maximum ROM during stretching between the procedures (p=0.06). The shear elastic modulus was significantly lower in the biceps femoris long head and semimembranosus than in the semitendinosus muscle (p<0.05). Static stretching with PKE and AKE stretching showed an increase in maximum ROM and a decrease in hamstring elasticity, but no difference was found between the methods. Both stretching protocols were effective for reducing elasticity of the biceps femoris long head and semimembranosus.

Correction: Acute Effect of Active and Passive Static Stretching on Elastic Modulus of the Hamstrings.

[This corrects the article DOI: 10.1055/a-0733-6957.].

Acute effects of static versus proprioceptive neuromuscular facilitation stretching volume on the maximum number of repetitions and perceived exertion

Abstract AIMS The purpose of this study was to examine the acute effects between different volumes of static stretching (SS) and proprioceptive neuromuscular facilitation (PNF) stretching (30 and 60 seconds) on the maximum number of repetitions at 40 and 80% 1RM and rating of perceived exertion (RPE). METHODS Eleven recreationally-trained women (26.45 ± 5.27 years) performed ten experimental protocols using a repeated measures crossover design: (a) 30 s of SS followed by 40% of 1RM (SS1); (b) 60 s of SS followed by 40% of 1RM (SS2); (c) 30 s of SS followed by 80% of 1RM (SS3); (d) 60 s of SS followed by 80% of 1RM (SS4); (e) 30 s of PNF followed by 40% of 1RM (PNF1); (f) 60 s of PNF followed by 40% of 1RM (PNF2); (g) 30 s of PNF followed by 80% of 1RM (PNF3); (h) 60 s of PNF followed by 80% of 1RM (PNF4); (i) 40% of 1RM with no stretching (NS1); and (j) 80% of 1RM with no stretching (NS2). In both stretching protocols, shoulder girdle muscle exercises were performed. RESULTSStretching volume did not seem to significantly decrease the number of repetitions after a bench press session (p>0.05). However, RPE was greater for PNF2 (28.5±1.0; p=0.016) when compared with PNF1 (26.9±1.9). CONCLUSION Stretching volume does not seem to decrease the maximum number of repetitions after a bench press session; however, greater stretching volume appears to increase perception of effort in women when using PNF stretching of longer duration.

Effect of Static Stretching with Superficial Cooling on Muscle Stiffness.

This study aimed to clarify the acute effect of static stretching (SS) with superficial cooling on dorsiflexion range of motion (DF ROM) and muscle stiffness. Sixteen healthy males participated in the cooling condition and a control condition in a random order. The DF ROM and the shear elastic modulus of medial gastrocnemius (MG) in the dominant leg were measured during passive dorsiflexion. All measurements were performed prior to (PRE) and immediately after 20 min of cooling or rested for 20 min (POST), followed by 2 min SS (POST SS). In cooling condition, DF ROM at POST and POST SS were significantly higher than that at PRE and DF ROM at POST SS was significantly higher than that at POST. In addition, the shear elastic modulus at POST was significantly higher than that at PRE and the shear elastic modulus at POST SS was significantly lower than those at PRE and POST. However, there were no significant differences in the percentage changes between PRE and POST SS between the cooling and control conditions. Our results showed that effects of SS with superficial cooling on increases in ROM and decrease in muscle stiffness were no more beneficial than those of SS alone.

Effects of 6-Week Static Stretching of Knee Extensors on Flexibility, Muscle Strength, Jump Performance, and Muscle Endurance.

Ikeda, N and Ryushi, T. Effects of 6-week static stretching of knee extensors on flexibility, muscle strength, jump performance, and muscle endurance. J Strength Cond Res 35(3): 715-723, 2021-The purpose of this study was to evaluate the changes in flexibility and muscular performance after stretching training for 6 weeks. Twelve healthy young men were assigned to a stretching group and 13 to a control group. The subjects of the stretching group performed static stretching of knee extensors for 6 weeks. Knee flexion range of motion (KFROM), leg extension strength, rate of force development (RFD) in leg extension, jump performance (squat and countermovement jump height, and index of rebound jump), and strength decrement index of 50 repetitions of isokinetic knee extension (muscle endurance) were measured before and after the interventions. In the stretching group, KFROM significantly increased from 145.2 ± 17.3 to 158.7 ± 6.3° (p < 0.05), whereas RFD significantly improved from 10,173 ± 2,401 to 11,883 ± 2,494 N·s-1 (p < 0.05). By contrast, leg extension strength and jump performance of each jump type did not improve significantly. Furthermore, muscle endurance decreased significantly. All variables remained unchanged in the control group. In conclusion, 6 weeks of stretching training of knee extensors improved KFROM and RFD in leg extension, but not leg extension strength and jump performance; moreover, muscle endurance decreased. These findings indicate that this stretching training protocol can be used by athletes in sports who require high flexibility and those who require high-power exertion.

Soleus H-Reflex Inhibition Decreases During 30 s Static Stretching of Plantar Flexors, Showing Two Recovery Steps.

During the period when the ankle joint is kept in a dorsiflexed position, the soleus (SOL) H-reflex is inhibited. The nature of this inhibition is not fully understood. One hypothesis is that the decrease in spinal excitability could be attributed to post-activation depression of muscle spindle afferents due to their higher firing rate during the stretch-and-hold procedure. As the static stretching position is maintained though, a partial restoration of the neurotransmitter is expected and should mirror a decrease in H-reflex inhibition. In the present study, we explored the time course of spinal excitability during a period of stretching. SOL H-reflex was elicited during a passive dorsiflexion movement, at 3, 6, 9, 12, 18, 21, and 25 s during maximal ankle dorsiflexion, during plantar flexion (PF) and after stretching, in 12 healthy young individuals. Measurements during passive dorsiflexion, PF and after stretching were all performed with the ankle at 100° angle; measurements during static stretching were performed at individual maximal dorsiflexion. H-reflex was strongly inhibited during the dorsiflexion movement and at maximal dorsiflexion (p < 0.0001) but recovered during PF and after stretching. During stretching H-reflex showed a recovery pattern (r = 0.836, P = 0.019) with two distinct recovery steps at 6 and 21 s into stretching. It is hypothesized that the H-reflex inhibition observed until 18 s into stretching is the result of post-activation depression of Ia afferent caused by the passive dorsiflexion movement needed to move the ankle into testing position. From 21 s into stretching, the lower inhibition could be caused by a weaker post-activation depression, inhibition from secondary afferents or post-synaptic inhibitions.

THE EFFECTS OF MUSCLE ENERGY TECHNIQUE AND STATIC STRETCHING OF GASTROCNEMIUS ON PAIN AND DISABILITY IN KNEE OSTEOARTHRITIS

BACKGROUND AND AIMS Knee Osteoarthritis (OA) is a degenerative disorder and a leading cause of disability associated with pain, restricted ROM and difficulty in performing Activities of Daily Living (ADLs). The aim of this study was to compare the effectiveness of Muscle Energy Technique (MET) and static stretching on gastrocnemius muscles among the patients suffering with knee OA. METHODOLOGY A 2-arm Randomized Control Trial was conducted at Ziauddin Hospital among 120 patients suffering with grade-II OA. Initial screening was conducted on the basis of Knee OOS. Group A received the MET whereas Group B received Static Stretching Technique both group received the treatment for three days/week for 4 weeks. RESULTS In initial evaluation, our results revealed that group A shows the KOOS score 0.43±0.10 that improved significantly after four weeks of treatment to 0.49±0.14. Our results revealed that at 95% CI, the KOOS score of patients significantly improved in both the groups p&lt;0.05