Effect of static and dynamic muscle stretching as part of warm up procedures on knee joint proprioception and strength

The Effects of Static Stretching 2-Hours Prior to a Traditional Warm-Up on Performance

Whereas prolonged static stretching (SS: >60-seconds per muscle) can increase range of motion (ROM) for up to 2-hours, it can also decrease maximal voluntary isometric contraction (MVIC) forces, countermovement (CMJ) and drop jump (DJ) heights, and muscle activation immediately after the stretching exercise. When an appropriate SS duration (<60-seconds per muscle) is incorporated into a dynamic warm-up, performance decrements are often trivial. However, there is a lack of studies that observed the effects of extensive SS (180-seconds) 2-hours prior to a dynamic warm-up. The objective was to investigate ROM and performance effects of prolonged SS, 2-hours prior to a traditional warm-up. This study investigated 9 female and 8 male healthy recreationally active, young adult participants on the effects of prolonged SS (180-seconds per muscle) of the quadriceps and hamstrings, 2-hours before a traditional warm-up compared to an active control condition on hip flexion ROM, knee extension and flexion MVIC forces, CMJ, DJ, and quadriceps and hamstrings electromyography (EMG). There were no significant changes in knee flexion/extension MVIC forces, EMG, CMJ, or DJ height. However, there was significant, small magnitude (p = 0.002) greater post-warm-up left hip flexion ROM (115.4° ± 17.2) than pre-SS (108.9° ± 17.13, Effect size [ES]: 0.28) and control post-warm-up (p = 0.05, ES: 0.31, 109.5° ± 20.55). Similarly, right hip flexion ROM (117.2° ± 16.5) also demonstrated significant small magnitude (p = 0.003) greater than the pre-SS (112.4° ± 18.4, ES: 0.22) and control post-warm-up (p = 0.046, ES: 0.33, 110.8° ± 20.5). Additionally, significant, large magnitude greater hip flexion ROM was observed with the women vs. men (ES: 1.29 - 1.34). Significant hip flexion ROM increases were not accompanied by significant changes in knee flexion/extension MVIC forces, EMG, or jump heights, suggesting that extensive SS can positively impact ROM without performance deficits when followed by a traditional warm-up, 2-hours after SS.

Placebo and nocebo interventions impact perceived but not actual proprioceptive accuracy

Changes in performance caused by positive and negative expectations (i.e., placebo and nocebo responses) were found to play an important role in many aspects of motor performance. This study aimed to test the impact of placebo/nocebo responses and the assumed moderating role of dispositional optimism and anxiety on proprioceptive accuracy, an essential aspect of motor functions. 78 undergraduate university students completed questionnaires assessing dispositional optimism, state anxiety, and motivation to cooperate, then were randomly assigned to three experimental groups. A sham subliminal electric stimulation was applied with claimed positive (placebo group, n = 26), negative (nocebo group, n = 26) or neutral (control group, n = 26) impact on proprioceptive accuracy. Proprioceptive accuracy was measured with active and passive versions of the Joint Position Reproduction task before and after the intervention. Expected and perceived changes in performance were also assessed; changes in state anxiety, optimism, and motivation to cooperate were used as control variables (covariates). Mixed analyses of variance indicated that the experimental manipulation did not affect actual proprioceptive accuracy but impacted expected and perceived performance. Adding the covariates to the models did not substantially change the results. Further, no significant association emerged between actual and perceived change in performance in the active test, and only a weak correlation was found in the passive test. Expected performance did not predict actual performance but predicted perceived performance in both tasks. The results suggest that only perceived (subjective) aspects of proprioceptive accuracy are susceptible to placebo and nocebo interventions.

What We Do Not Know About Stretching in Healthy Athletes: A Scoping Review with Evidence Gap Map from 300 Trials

BACKGROUND

Stretching has garnered significant attention in sports sciences, resulting in numerous studies. However, there is no comprehensive overview on investigation of stretching in healthy athletes.

OBJECTIVES

To perform a systematic scoping review with an evidence gap map of stretching studies in healthy athletes, identify current gaps in the literature, and provide stakeholders with priorities for future research.

METHODS

Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 and PRISMA-ScR guidelines were followed. We included studies comprising healthy athletes exposed to acute and/or chronic stretching interventions. Six databases were searched (CINAHL, EMBASE, PubMed, Scopus, SPORTDiscus, and Web of Science) until 1 January 2023. The relevant data were narratively synthesized; quantitative data summaries were provided for key data items. An evidence gap map was developed to offer an overview of the existing research and relevant gaps.

RESULTS

Of ~ 220,000 screened records, we included 300 trials involving 7080 athletes [mostly males (~ 65% versus ~ 20% female, and ~ 15% unreported) under 36 years of age; tiers 2 and 3 of the Participant Classification Framework] across 43 sports. Sports requiring extreme range of motion (e.g., gymnastics) were underrepresented. Most trials assessed the acute effects of stretching, with chronic effects being scrutinized in less than 20% of trials. Chronic interventions averaged 7.4 ± 5.1 weeks and never exceeded 6 months. Most trials (~ 85%) implemented stretching within the warm-up, with other application timings (e.g., post-exercise) being under-researched. Most trials examined static active stretching (62.3%), followed by dynamic stretching (38.3%) and proprioceptive neuromuscular facilitation (PNF) stretching (12.0%), with scarce research on alternative methods (e.g., ballistic stretching). Comparators were mostly limited to passive controls, with ~ 25% of trials including active controls (e.g., strength training). The lower limbs were primarily targeted by interventions (~ 75%). Reporting of dose was heterogeneous in style (e.g., 10 repetitions versus 10 s for dynamic stretching) and completeness of information (i.e., with disparities in the comprehensiveness of the provided information). Most trials (~ 90%) reported performance-related outcomes (mainly strength/power and range of motion); sport-specific outcomes were collected in less than 15% of trials. Biomechanical, physiological, and neural/psychological outcomes were assessed sparsely and heterogeneously; only five trials investigated injury-related outcomes.

CONCLUSIONS

There is room for improvement, with many areas of research on stretching being underexplored and others currently too heterogeneous for reliable comparisons between studies. There is limited representation of elite-level athletes (~ 5% tier 4 and no tier 5) and underpowered sample sizes (≤ 20 participants). Research was biased toward adult male athletes of sports not requiring extreme ranges of motion, and mostly assessed the acute effects of static active stretching and dynamic stretching during the warm-up. Dose-response relationships remain largely underexplored. Outcomes were mostly limited to general performance testing. Injury prevention and other effects of stretching remain poorly investigated. These relevant research gaps should be prioritized by funding policies.

REGISTRATION

OSF project ( https://osf.io/6auyj/ ) and registration ( https://osf.io/gu8ya ).

Potential Effects of Dynamic Stretching on Injury Incidence of Athletes: A Narrative Review of Risk Factors

The use of dynamic stretching as a replacement for static stretching in the warm-up is widespread based on the reports of static stretching-induced performance impairments. While acute and chronic static stretching has been reported to reduce musculotendinous injuries, especially with explosive and change of direction actions, the influence of dynamic stretching on injury incidence lacks a similar volume of literature for acute and chronic responses. It was the objective of this narrative review to examine the acute and training effects of dynamic stretching on injury incidence and possible moderating variables such as dynamic stretching effects on range of motion, strength, balance, proprioception, muscle morphology, and psycho-physiological responses. One study demonstrated no significant difference regarding injury incidence when comparing a dynamic stretching-only group versus a combined dynamic stretching plus static stretching group. The only other study examined functional dynamic stretching training with injured dancers and reported improved ankle joint stability. However, several studies have shown that dynamic activity with some dynamic stretching exercises within a warm-up consistently demonstrates positive effects on injury incidence. Regarding moderating variables, while there is evidence that an acute bout of dynamic stretching can enhance range of motion, the acute and training effects of dynamic stretching on strength, balance, proprioception, and musculotendinous stiffness/compliance are less clear. The acute effects of dynamic stretching on thixotropic effects and psycho-physiological responses could be beneficial for injury reduction. However, the overall conflicting studies and a lack of substantial literature compared with SS effects points to a need for more extensive studies in this area.

Effects of Plantar Flexor Stretching on Static and Dynamic Balance in Healthy Adults

Stretching can affect balance ability by generating biomechanical and physiological changes in the postural muscles. Stretching of the lower extremity muscles can greatly affect posture maintenance strategies and balance ability. However, the relationship between stretching and balance ability has not been clarified. Therefore, this study aimed to investigate the effect of plantar flexor stretching on balance ability. Forty-four healthy young adults were randomly assigned to four groups (static stretching, dynamic stretching, ballistic stretching, and control). Ankle joint range of motion, static balance ability, and dynamic balance ability were evaluated before, immediately after, and 20 min after stretching. Stretching did not affect balance ability in the open-eye condition. After stretching, the sway area was significantly reduced in the closed-eye condition (p < 0.05). After stretching, the reach distance of dynamic balance ability increased significantly (p < 0.05). The results show that plantar flexor stretching can positively affect balance ability. Therefore, plantar flexor stretching should be considered a rehabilitation method to improve balance.

The Clinical Benefits of a Dynamic vs. Static Component as Part of a Comprehensive Warm-Up for Recreational Sports Players with Clinical Histories of Hamstring Injuries: A Randomized Clinical Trial

Background: Few previous studies have analyzed the effects of certain specific static and dynamic warm-up components on recreational sports players with a previous hamstring injury. Therefore, the aim of this study was to analyze changes in some modifiable and external risk factors after (immediately and in a follow-up assessment after 10 min) a static or dynamic warm-up program on recreational sports players with a previous hamstring injury. Methods: A total of 62 participants were randomized into 2 groups: static warm-up (SW) (n = 31) or dynamic warm-up (DW) (n = 31). Range of movement (RoM), perceived pain, the pressure−pain threshold, and joint position sense were assessed at baseline, immediately after the intervention and 10 min afterwards. The intervention for the SW (hot pack procedures in both hamstring muscles) lasted 20 min. The DW intervention consisted of a running exercise performed on a treadmill for 10 min. Results: Both groups showed statistically significant changes (p ≤ 0.05) in the primary outcomes (perceived pain and the pressure−pain threshold) at the three measurement times (this was also true for RoM for the SW group, with statistically significant differences only between times from the baseline to the 10-min follow-up; p ≤ 0.05, d = 0.23). The intra-group secondary outcome showed no statistically significant changes (p > 0.05) in both groups (except for the period from the baseline−immediately after in the DW group; p ≤ 0.05, d = 0.53). The comparison between groups showed no statistically significant differences for any of the variables analyzed. (p ≥ 0.05). Conclusion: The present findings suggest that both specific warm-up modalities seem to positively influence perceived pain on stretching and the pressure threshold; however, the significant reduction in the joint repositioning error and the larger effect sizes observed in the DW group suggest that this method has a greater beneficial impact in recreational sports players with clinical histories of hamstring injuries.

The Effectiveness of Proprioceptive Training for Improving Motor Performance and Motor Dysfunction: A Systematic Review

Objective

Proprioceptive training is any intervention aiming to improve proprioceptive function with the ultimate goal to enhance motor function and performance. It has been promoted as an approach to enhance athletic performance and as a tool for sensorimotor rehabilitation. Numerous studies sought to provide evidence on the effectiveness of the approach. However, many different training regimes claiming to train proprioception report a variety of sensorimotor measures that are not directly comparable. This, in turn, makes it difficult to assess effectiveness across approaches. It is the objective of this study to systematically review recent empirical evidence to gain an understanding of which outcome measures are most sensitive, which populations may benefit most from proprioceptive training, and what are the effects on proprioceptive and motor systems.

Methods

Four major databases were searched. The following inclusion criteria were applied: (1) A quantified pre- and post-treatment measure of proprioceptive function. (2) An intervention or training program believed to influence or enhance proprioceptive function. (3) Contained at least one form of treatment or outcome measure that is indicative of somatosensory function and not confounded by information from other sensory modalities. 4) The study reported of at least one quantified measure of motor performance.

Results

Of the 3,297 articles identified by the database search, 70 studies met the inclusion criteria and were included for further review. Across studies, proprioceptive training led to comparable gains in both proprioceptive (+46%) and motor performance (+45%). The majority of studies (50/70) applied active movement interventions. Interventions applying somatosensory stimulation were most successful in clinical populations. Joint position sense error (JPSE) was the most commonly used proprioceptive measure and presents a reliable and feasible measure for clinical use.

Conclusion

Proprioceptive training can lead to significant improvements in proprioceptive and motor function across a range healthy and clinical populations. Regimens requiring active movement of the trainee tended to be most successful in improving sensorimotor performance. Conclusive evidence on how long training gains are retained is still lacking. There is no solid evidence about the underlying long-term neuroplastic changes associated proprioceptive training.

The effect of static stretching of agonist and antagonist muscles on knee joint position sense

Background/Aims

Proprioception acuity is important in sports activities and stretching is widely used in warm-up programmes. The main objective of this study was to evaluate if a warm-up programme with and without stretching flexors and extensors muscles could affect knee joint position sense.

Methods

The effects of different stretching regimens on joint position sense were examined. A total of 12 semi-professional football players completed four warm-up sessions over 4 weeks: standard warm-up programme; standard warm-up programme with quadriceps stretching; standard warm-up programme with hamstring stretching; and standard warm-up programme with stretching of both quadriceps and hamstrings. Open kinetic chain knee joint position sense was estimated from the ability to reproduce the three target angles (20°, 45° and 60° knee flexion) in the dominant limb before and after the intervention.

Results

In the absolute angular error, there was a statistically significant three-way interaction between the warm-up programme, target angle and time (F (6, 54)=6.88, P=0.001). Findings of post-hoc analysis demonstrated that there was a statistically significant difference between the pre- and post-stretching of hamstrings for the target angles of 20° (4.70 vs 1.57, P=0.01), 45° (1.70 vs 4.50, P=0.02), and 60° (1.93 vs 4.20, P=0.02). In the relative angular error, interaction of time by the warm-up programme was significant (F (3, 27)=3.41, P=0.03).

Conclusions

The warm-up programme with static stretching of hamstrings had a negative effect on open kinetic chain knee joint position sense during the flexion to extension repositioning task, which may not only have a negative effect on performance of athletes as a part of warm-up exercises, but may also lead to further injuries.

Effects of two different stretching techniques on proprioception and hamstring flexibility: a pilot study

Aim: This study aimed to compare the immediate and long-term effect of proprioceptive neuromuscular facilitation (PNF) contract-relax-antagonist-contract (CRAC) exercises versus static stretching on proprioception and flexibility in males with hamstring shortness. Patients & methods: Knee extension angle test was used to measure flexibility and isokinetic dynamometer to evaluate proprioception. Assessments were evaluated at baseline, after first exercise and eighth week. The hamstring stretching was applied 3 days a week for 8 weeks. Results: Flexibility and position sense were similar in the immediate and long term (p > 0.05). However, the motion sense increased significantly in long term within the PNF CRAC group (p = 0.02). Conclusion: Both stretching exercises are effective for improving flexibility. Moreover, PNF CRAC improved motion sense more than static stretching in the long term. Clinical trial registration number: NCT04026646.

Effects of Warm-up on Hamstring Stiffness, Stress-Relaxation, Flexibility and Knee Proprioception in Young Soccer Players

CONTEXT

Nerves or fascia may limit motion in young soccer players, thereby contributing to frequent hamstring injuries. Nerve gliding exercises and self-myofascial release techniques may enhance the range of motion.

OBJECTIVE

The aim of this study was to compare the acute effect of foam rolling (FR) and neurodynamic nerve gliding (NDNG) on hamstring flexibility, passive stiffness, viscoelasticity and proprioception during the warm-up of soccer players.

DESIGN

Crossover study design.

SETTING

Research laboratory.

PARTICIPANTS

Fifteen male soccer players on the same team (age 18.0 ± 1.4 years, body mass 76.9 ± 7.8 kg, height 183 ± 6 cm).

INTERVENTION

FR and NDNG included six sets of 45 s with 15 s rest between each set. Over a two-week period subjects performed NDNG and FR on two separate occasions.

MAIN OUTCOME MEASURE(S)

Hip flexion angle (SLR), knee extension range of motion (ROM), knee joint position sense (AKJPS), hamstring passive resistance torque (PRT), stiffness (STFmax and STF80%) and viscoelasticity (stress-relaxation test (SRT)).

RESULTS

A significant interaction between time and intervention was found for knee ROM (p = 0.017), PRT (p = 0.044), and STFmax (p = 0.042). NDNG induced an increase in ROM (p = 0.011), PRT (p = 0.008), and STFmax (p = 0.030). Both NDNG and FR induced an increase in SLR (p < 0.001). No interaction or main effects was found for SRT and AKJPS.

CONCLUSION

The inclusion of NDNG in the warm-up routine increased the ROM more in comparison with FR and may be of benefit to soccer players.

Contributions of exercise-induced fatigue versus intertrial tendon vibration on visual-proprioceptive weighting for goal-directed movement

It has been argued that exercise-induced muscle fatigue and tendon vibration can alter proprioceptive estimates of limb position. While exercise-induced muscle fatigue may also affect central efferent processes related to limb position sense, tendon vibration specifically targets peripheral afferent signals. It is unclear, however, whether either of these perturbations (i.e., muscle fatigue or tendon vibration) can alter the multisensory weighting processes preceding goal-directed movements. The current study sought to specifically explore visual-proprioceptive weighting before or after eccentric exercise-induced antagonist muscle fatigue (experiment 1) versus with or without intertrial simultaneous agonist-antagonist tendon vibration (experiment 2). To assess sensory weighting, a visual-proprioceptive mismatch between the participant's actual initial starting position and the associated visual cursor position was employed. This method provides an estimate of the participant's reliance on the proprioceptive or visual starting limb position for their aiming movements. Although there was clear evidence of muscle fatigue, there was no systematic alteration of proprioceptive weighting after eccentric exercise and no relationship between sensory weighting and the level of fatigue. On the other hand, participants' reliance on their actual (proprioceptive) limb position was systematically reduced when exposed to agonist-antagonist tendon vibration before each aiming movement. These findings provide seminal evidence that intertrial tendon vibration, but not exercise-induced fatigue, can alter the reliability of proprioceptive estimates and the relative contributions of visual and proprioceptive information for goal-directed movement.NEW & NOTEWORTHY Previous work has used muscle fatigue or tendon vibration to perturb proprioceptive limb position estimates. This study sought to determine whether exercise-induced muscle fatigue versus intertrial tendon vibration can alter multisensory weighting for upper limb-aiming movements. By introducing a discrepancy between participants' actual proprioceptive and visual finger position, this study provides seminal evidence for the reduction of proprioceptive-to-visual weighting using intertrial tendon vibration but no evidence for a systematic reduction following exercise-induced fatigue.

Immediate effects of neurodynamic nerve gliding versus static stretching on hamstring neuromechanical properties

PURPOSE

We investigated the immediate effects of neurodynamic nerve gliding (ND) on hamstring flexibility, viscoelasticity, and mechanosensitivity, compared with traditional static stretching (ST).

METHODS

Twenty-two physically active men aged 21.9 ± 1.9 years were divided randomly into two equal intervention groups using ST or ND. An isokinetic dynamometer was used to measure the active knee joint position sense, perform passive knee extension, record the passive extension range of motion (ROM) and the passive-resistive torque of hamstrings. Stiffness was determined from the slope of the passive torque-angle relationship. A stress relaxation test (SRT) was performed to analyze the viscoelastic behavior of the hamstrings. The passive straight leg raise (SLR) test was used to evaluate hamstring flexibility.

RESULTS

A significant interaction was observed for ROM and passive ultimate stiffness, reflected by an increase in these indicators after ND but not after SD. SLR increased significantly in both groups. After ST, a significantly faster initial stress relaxation was observed over the first 4 s. than after ND. There was no significant change in the active knee joint position sense.

CONCLUSIONS

ND provided a slightly greater increase in hamstring extensibility and passive stiffness, possibly by decreasing nerve tension and increasing strain in connective tissues than ST. The ST mostly affected the viscoelastic behavior of the hamstrings, but neither intervention had a significant impact on proprioception.

Nonlinear approach to study the acute effects of static and dynamic stretching on local dynamic stability in lower extremity joint kinematics and muscular activity during pedalling

Researchers have reported contradictory results on the effect of static and dynamic stretching on subsequent performance. Due to the importance of performance through static and dynamic stretching, the aim of this study is to investigate the acute effects of static and dynamic stretching protocols on local dynamic stability in lower extremity joint kinematics and muscular activities during pedalling using a nonlinear dynamics approach. Using a randomised crossover trial design, fifteen active males participated voluntarily in this research (mass: 69.02 ± 10.52 kg, height: 174.00 ± 6.74 cm, and age: 21.20 ± 1.47 years) and completed a pedalling trial in situations of without stretching (WS), after static (SS), and dynamic stretching (DS) of lower extremity. The lower extremity joint angles in the sagittal plane and the electrical activity of soleus, gastrocnemius medialis, tibialis anterior, vastus medialis, biceps femoris, and rectus femoris muscles were collected during 30 pedalling cycles at 70 rates per minute. The results of the repeated measure ANOVA indicated that the knee and ankle angle largest LyE was significantly lower in DS compared to WS and SS. The largest LyE in muscle activity is also significantly lower for all the muscles after DS compared to WS and SS (P ≤ 0.05). Regarding the positive effects of DS on the joints and the muscle activity local dynamic stability, it is suggested to use DS than SS in the warm-up program before repetitive activities like pedalling.

Differential Effects of Different Warm-up Protocols on Repeated Sprints-Induced Muscle Damage

Chen, CH, Ye, X, Wang, YT, Chen, YS, and Tseng, WC. Differential effects of different warm-up protocols on repeated sprints-induced muscle damage. J Strength Cond Res 32(11): 3276-3284, 2018-The purpose of this investigation was to examine whether adding a set of hamstring resistance exercise or dynamic stretching to a regular running-based warm-up before a bout of repeated sprints provides protective effects against the sprinting-induced muscle damage. Twelve elite tennis players participated in this study. After the familiarization, subjects completed 3 separate randomly sequenced experimental visits, during which 3 different warm-up interventions were performed before the muscle-damaging protocol (12 sets of 30-m maximal repeated sprints): 5 minutes of running (control); control with single leg slide curl (SLC); and control with active hamstring stretching (AHS). Before, immediately (POST0), 1 day (POST1), and 2 days after (POST2) the sprints, hip flexion passive range of motion, hamstring muscle thickness and pennation angle, muscle stiffness, and knee flexion concentric peak torque were measured. Repeated sprints have induced muscle damage in all 3 visits. For AHS, the muscle thickness and stiffness values at POST2 were significantly lower than those of other 2 protocols. In addition, the decrements of concentric strength at POST0, POST1, and POST2 for AHS were also significantly less than those of control and SLC. Therefore, adding a set of dynamic hamstrings stretching to a regular warm-up protocol before repeated sprints has protective effect on the sprinting-induced muscle damage. Athletes whose competitions are densely scheduled (e.g., tennis player in a tournament) may take advantage of this strategy to facilitate muscle recovery from the potential muscle damage, thus, to get maximal recovery for the subsequent competitions.

Analysis of Lower Extremity Proprioception for Anterior Cruciate Ligament Injury Prevention: Current Opinion

Lower extremity musculoskeletal injuries-such as ACL injury-are common, and the majority of those injuries occur without external player contact. In order to prevent non-contact musculoskeletal injuries, athletes must rely on accurate sensory information (such as visual, vestibular, and somatosensory) and stabilize joints during athletic tasks. Previously, proprioception tests (the senses of joint position, movement, tension or force) have been examined using static tests. Due to the role of proprioception in achievement of joint stability, it is essential to explore the development of dynamic proprioception tests. In this current opinion, the basic background on proprioception is covered, and the research gaps and future directions are discussed.