Chronic effect of different types of stretching on ankle dorsiflexion range of motion: Systematic review and meta-analysis

Discussing Conflicting Explanatory Approaches in Flexibility Training Under Consideration of Physiology: A Narrative Review

The mechanisms underlying range of motion enhancements via flexibility training discussed in the literature show high heterogeneity in research methodology and study findings. In addition, scientific conclusions are mostly based on functional observations while studies considering the underlying physiology are less common. However, understanding the underlying mechanisms that contribute to an improved range of motion through stretching is crucial for conducting comparable studies with sound designs, optimising training routines and accurately interpreting resulting outcomes. While there seems to be no evidence to attribute acute range of motion increases as well as changes in muscle and tendon stiffness and pain perception specifically to stretching or foam rolling, the role of general warm-up effects is discussed in this paper. Additionally, the role of mechanical tension applied to greater muscle lengths for range of motion improvement will be discussed. Thus, it is suggested that physical training stressors can be seen as external stimuli that control gene expression via the targeted stimulation of transcription factors, leading to structural adaptations due to enhanced protein synthesis. Hence, the possible role of serial sarcomerogenesis in altering pain perception, reducing muscle stiffness and passive torque, or changes in the optimal joint angle for force development is considered as well as alternative interventions with a potential impact on anabolic pathways. As there are limited possibilities to directly measure serial sarcomere number, longitudinal muscle hypertrophy remains without direct evidence. The available literature does not demonstrate the necessity of only using specific flexibility training routines such as stretching to enhance acute or chronic range of motion.

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 ).

Effects of chronic static stretching interventions on jumping and sprinting performance-a systematic review with multilevel meta-analysis

When improving athletic performance in sports with high-speed strength demands such as soccer, basketball, or track and field, the most common training method might be resistance training and plyometrics. Since a link between strength capacity and speed strength exists and recently published literature suggested chronic stretching routines may enhance maximum strength and hypertrophy, this review was performed to explore potential benefits on athletic performance. Based on current literature, a beneficial effect of static stretching on jumping and sprinting performance was hypothesized. A systematic literature search was conducted using PubMed, Web of Science and Google scholar. In general, 14 studies revealed 29 effect sizes (ES) (20 for jumping, nine for sprinting). Subgroup analyses for jump performance were conducted for short- long- and no stretch shortening cycle trials. Qualitative evaluation was supplemented by performing a multilevel meta-analysis via R (Package: metafor). Significant positive results were documented in six out of 20 jump tests and in six out of nine sprint tests, while two studies reported negative adaptations. Quantitative data analyses indicated a positive but trivial magnitude of change on jumping performance (ES:0.16, p = 0.04), while all subgroup analyses did not support a positive effect (p = 0.09-0.44). No significant influence of static stretching on sprint performance was obtained (p = 0.08). Stretching does not seem to induce a sufficient stimulus to meaningfully enhance jumping and sprinting performance, which could possibly attributed to small weekly training volumes or lack of intensity.

Chronic effects of stretching on range of motion with consideration of potential moderating variables: A systematic review with meta-analysis

BACKGROUND

It is well known that stretch training can induce prolonged increases in joint range of motion (ROM). However, to date more information is needed regarding which training variables might have greater influence on improvements in flexibility. Thus, the purpose of this meta-analysis was to investigate the effects of stretch training on ROM in healthy participants by considering potential moderating variables, such as stretching technique, intensity, duration, frequency, and muscles stretched, as well as sex-specific, age-specific, and/or trained state-specific adaptations to stretch training.

METHODS

We searched through PubMed, Scopus, Web of Science, and SportDiscus to find eligible studies and, finally, assessed the results from 77 studies and 186 effect sizes by applying a random-effect meta-analysis. Moreover, by applying a mixed-effect model, we performed the respective subgroup analyses. To find potential relationships between stretch duration or age and effect sizes, we performed a meta-regression.

RESULTS

We found a significant overall effect, indicating that stretch training can increase ROM with a moderate effect compared to the controls (effect size = -1.002; Z = -12.074; 95% confidence interval: -1.165 to -0.840; p < 0.001; I2 = 74.97). Subgroup analysis showed a significant difference between the stretching techniques (p = 0.01) indicating that proprioceptive neuromuscular facilitation and static stretching produced greater ROM than did ballistic/dynamic stretching. Moreover, there was a significant effect between the sexes (p = 0.04), indicating that females showed higher gains in ROM compared to males. However, further moderating analysis showed no significant relation or difference.

CONCLUSION

When the goal is to maximize ROM in the long term, proprioceptive neuromuscular facilitation or static stretching, rather than ballistic/dynamic stretching, should be applied. Something to consider in future research as well as sports practice is that neither volume, intensity, nor frequency of stretching were found to play a significant role in ROM yields.

Effectiveness of instrument assisted soft tissue mobilization versus foam rolling on trigger point release in calf muscles

BACKGROUND

Instrument assisted soft tissue mobilization and foam rolling are two techniques that have been proven effective in treating Myofascial Trigger Points, irrespective of the type of trigger point. However, little is known about the comparative effectiveness of Instrument assisted soft tissue mobilization and foam rolling. This study proposed to evaluate the effectiveness of either technique on plantar flexors trigger points, ankle dorsiflexion, and lower limb power present in the calf muscles in non-symptomatic patients.

METHOD

Forty-two subjects with bilateral calf muscle tightness, at least one trigger point in the calf muscle, and fulfilling the inclusion criteria were randomly assigned to either of the groups. Group A was treated for gastrocnemius and soleus trigger points using Instrument assisted soft tissue mobilization and Group B was treated using the Foam Rolling method. Treatment was given every alternate day, a total of 3 sessions. Subjects were evaluated on 1st and 3rd sessions for pre-post differences of ankle dorsiflexion Range of motion in weight bearing and non-weight bearing position, pressure pain threshold for gastrocnemius trigger point 1(G1), 2(G2), and soleus point 1(S1) on both sides, and lower limb power.

RESULT

Within group analyses, both groups had shown statistically significant results for all parameters except gastrocnemius trigger point 2 of foam rolling. For between group comparison foam rolling had a statistically significant result in non-weight bearing ankle dorsiflexion range of motion.

CONCLUSION

Both Instrument assisted soft tissue mobilization and Foam rolling were equally effective for treating calf trigger points. But foam rolling was more effective in improving ankle dorsiflexion range of motion.

Effect of PNF stretching performed in the AKE position on hip, knee, and ankle flexibility

BACKGROUND

To measure hamstring flexibility, the active knee extension (AKE) test is preferred over the straight leg raise (SLR) test as it can be used to measure hamstring flexibility more selectively. However, hamstring stretching is primarily conducted in the SLR position (maximal hip flexion in the supine position) as it allows for maximal hip flexion in the supine position.

OBJECTIVE

This study evaluates the effects of proprioceptive neuromuscular facilitation (PNF) stretching in the AKE position (maximal knee extension with 90∘ flexion of the hip in the supine position) on hip, knee, and ankle flexibility.

METHODS

SLR, AKE, and active dorsiflexion (ADF) tests were used to determine the range of motion (ROM) before (pre-ROM) and after (post-ROM) stretching. PNF stretching consisted of maximal isometric knee flexion at the end range with external resistance to prevent knee flexion. One set of PNF stretches (five trials of six seconds each) was conducted.

RESULTS

The post-ROMs of hip, knee, and ankle measured via the SLR, AKE, and ADF tests, respectively, were significantly higher than the pre-ROMs.

CONCLUSIONS

The improvement in knee flexibility was greater than the improvement in hip and ankle flexibility. The AKE position is recommended in clinical settings during PNF stretching for individuals with hamstring tightness. Furthermore, PNF stretching in the AKE position increases the ADF ROM.

Physiology of Stretch-Mediated Hypertrophy and Strength Increases: A Narrative Review

Increasing muscle strength and cross-sectional area is of crucial importance to improve or maintain physical function in musculoskeletal rehabilitation and sports performance. Decreases in muscular performance are experienced in phases of reduced physical activity or immobilization. These decrements highlight the need for alternative, easily accessible training regimens for a sedentary population to improve rehabilitation and injury prevention routines. Commonly, muscle hypertrophy and strength increases are associated with resistance training, typically performed in a training facility. Mechanical tension, which is usually induced with resistance machines and devices, is known to be an important factor that stimulates the underlying signaling pathways to enhance protein synthesis. Findings from animal studies suggest an alternative means to induce mechanical tension to enhance protein synthesis, and therefore muscle hypertrophy by inducing high-volume stretching. Thus, this narrative review discusses mechanical tension-induced physiological adaptations and their impact on muscle hypertrophy and strength gains. Furthermore, research addressing stretch-induced hypertrophy is critically analyzed. Derived from animal research, the stretching literature exploring the impact of static stretching on morphological and functional adaptations was reviewed and critically discussed. No studies have investigated the underlying physiological mechanisms in humans yet, and thus the underlying mechanisms remain speculative and must be discussed in the light of animal research. However, studies that reported functional and morphological increases in humans commonly used stretching durations of > 30 min per session of the plantar flexors, indicating the importance of high stretching volume, if the aim is to increase muscle mass and maximum strength. Therefore, the practical applicability seems limited to settings without access to resistance training (e.g., in an immobilized state at the start of rehabilitation), as resistance training seems to be more time efficient. Nevertheless, further research is needed to generate evidence in different human populations (athletes, sedentary individuals, and rehabilitation patients) and to quantify stretching intensity.

Remote effects of a 7-week combined stretching and foam rolling training intervention of the plantar foot sole on the function and structure of the triceps surae

It is known that a single bout of foam rolling (FR) or stretching can induce changes in range of motion (ROM) and performance in non-directly adjoining areas of the dorsal chain (i.e., remote effects). However, to date, it is not known if such effects exist following long-term interventions. Thus, the purpose of this study was to investigate the remote effects of a 7-week combined stretching and FR training intervention of the plantar foot sole. Thirty-eight recreational athletes were randomly assigned to either an intervention (n = 20) or control (n = 18) group. The intervention group performed stretching and FR exercises of the plantar foot sole for 7 weeks. Before and after the intervention, the dorsiflexion ankle ROM, passive resistive torque at maximum angle (PRTmax) and at a fixed angle, as well as maximum voluntary isometric contraction (MVIC) torque, were measured with a dynamometer. Gastrocnemius medialis and lateralis stiffness was assessed with shear wave elastography. The results showed no interaction effect for any of the parameters. There was a time effect indicating an increase in MVIC and PRTmax, which was more pronounced in the intervention group (+ 7.4 (95% CI 2.5-12.4),  + 4.5 (95% CI - 0.2-9.2)) than the control group (+ 3.6 (95% CI - 1.4-8.6),  + 4.0 (95% CI - 2.2 to 10.2)). The results indicate no or minor remote effects of combined stretching and FR of the foot sole in the ankle joint. Potential non-significant changes in ROM were accompanied with an increase in stretch tolerance, but not with changes in muscle structure.

Long-term static stretching can decrease muscle stiffness: A systematic review and meta-analysis

Stretch training increases the range of motion of a joint. However, to date, the mechanisms behind such a stretching effect are not well understood. An earlier meta-analysis on several studies reported no changes in the passive properties of a muscle (i.e., muscle stiffness) following long-term stretch training with various types of stretching (static, dynamic, and proprioceptive neuromuscular stretching). However, in recent years, an increasing number of papers have reported the effects of long-term static stretching on muscle stiffness. The purpose of the present study was to examine the long-term (≥2 weeks) effect of static stretching training on muscle stiffness. PubMed, Web of Science, and EBSCO published before December 28, 2022, were searched and 10 papers met the inclusion criteria for meta-analysis. By applying a mixed-effect model, subgroup analyses, which included comparisons of sex (male vs. mixed sex) and type of muscle stiffness assessment (calculated from the muscle-tendon junction vs. shear modulus), were performed. Furthermore, a meta-regression was conducted to examine the effect of total stretching duration on muscle stiffness. The result of the meta-analysis showed a moderate decrease in muscle stiffness after 3-12 weeks of static stretch training compared to a control condition (effect size = -0.749, p < 0.001, I2  = 56.245). Subgroup analyses revealed no significant differences between sex (p = 0.131) and type of muscle stiffness assessment (p = 0.813). Moreover, there was no significant relationship between total stretching duration and muscle stiffness (p = 0.881).

Using Daily Stretching to Counteract Performance Decreases as a Result of Reduced Physical Activity-A Controlled Trial

There are many reasons for reduced physical activity leading to reduced maximal strength and sport-specific performance, such as jumping performance. These include pandemic lockdowns, serious injury, or prolonged sitting in daily work life. Consequently, such circumstances can contribute to increased morbidity and reduced physical performance. Therefore, a demand for space-saving and home-based training routines to counteract decreases in physical performance is suggested in the literature. This study aimed to investigate the possibility of using daily static stretching using a stretching board to counteract inactivity-related decreases in performance. Thirty-five (35) participants were either allocated to an intervention group (IG), performing a daily ten-minute stretch training combined with reduced physical activity or a reduced physical activity-only group (rPA). The effects on maximal voluntary contraction, range of motion using the knee-to-wall test, countermovement jump height (CMJ_height), squat jump height (SJ_height), drop jump height (DJ_height), contact time (DJ_ct) and the reactive strength index (DJ_RSI) were evaluated using a pre-test-post-test design. The rPA group reported reduced physical activity because of lockdown. Results showed significant decreases in flexibility and jump performance (d = -0.11--0.36, p = 0.004-0.046) within the six weeks intervention period with the rPA group. In contrast, the IG showed significant increases in MVC90 (d = 0.3, p < 0.001) and ROM (d = 0.44, p < 0.001) with significant improvements in SJ_height (d = 0.14, p = 0.002), while no change was measured for CMJ_height and DJ performance. Hence, 10 min of daily stretching seems to be sufficient to counteract inactivity-related performance decreases in young and healthy participants.

Influence of One Hour versus Two Hours of Daily Static Stretching for Six Weeks Using a Calf-Muscle-Stretching Orthosis on Maximal Strength

Rebuilding strength capacity is of crucial importance in rehabilitation since significant atrophy due to immobilization after injury and/or surgery can be assumed. To increase maximal strength (MSt), strength training is commonly used. The literature regarding animal studies show that long-lasting static stretching (LStr) interventions can also produce significant improvements in MSt with a dose-response relationship, with stretching times ranging from 30 min to 24 h per day; however, there is limited evidence in human studies. Consequently, the aim of this study is to investigate the dose-response relationship of long-lasting static stretching on MSt. A total of 70 active participants (f = 30, m = 39; age: 27.4 ± 4.4 years; height: 175.8 ± 2.1 cm; and weight: 79.5 ± 5.9 kg) were divided into three groups: IG1 and IG2 both performed unilateral stretching continuously for one (IG1) or two hours (IG2), respectively, per day for six weeks, while the CG served as the non-intervened control. MSt was determined in the plantar flexors in the intervened as well as in the non-intervened control leg to investigate the contralateral force transfer. Two-way ANOVA showed significant interaction effects for MSt in the intervened leg (ƞ² = 0.325, p < 0.001) and in the contralateral control leg (ƞ² = 0.123, p = 0.009), dependent upon stretching time. From this, it can be hypothesized that stretching duration had an influence on MSt increases, but both durations were sufficient to induce significant enhancements in MSt. Thus, possible applications in rehabilitation can be assumed, e.g., if no strength training can be performed, atrophy could instead be reduced by performing long-lasting static stretch training.

The Effects of Foam Rolling Training on Performance Parameters: A Systematic Review and Meta-Analysis including Controlled and Randomized Controlled Trials

Foam rolling (FR) is a new and popular technique for increasing range of motion. While there are a few studies that demonstrate increased performance measures after an acute bout of FR, the overall evidence indicates trivial performance benefits. As there have been no meta-analyses on the effects of chronic FR on performance, the objective of this systematic meta-analytical review was to quantify the effects of FR training on performance. We searched PubMed, Scopus, the Cochrane library, and Web of Science for FR training studies with a duration greater than two weeks, and found eight relevant studies. We used a random effect meta-analysis that employed a mixed-effect model to identify subgroup analyses. GRADE analysis was used to gauge the quality of the evidence obtained from this meta-analysis. Egger's regression intercept test (intercept 1.79; p = 0.62) and an average PEDro score of 6.25 (±0.89) indicated no or low risk of reporting bias, respectively. GRADE analysis indicated that we can be moderately confident in the effect estimates. The meta-analysis found no significant difference between FR and control conditions (ES = -0.294; p = 0.281; I² = 73.68). Analyses of the moderating variables showed no significant differences between randomized control vs. controlled trials (Q = 0.183; p = 0.67) and no relationship between ages (R² = 0.10; p = 0.37), weeks of intervention (R² = 0.17; p = 0.35), and total load of FR (R² = 0.24; p = 0.11). In conclusion, there were no significant performance changes with FR training and no specific circumstances leading to performance changes following FR training exceeding two weeks.

Influence of Long-Lasting Static Stretching on Maximal Strength, Muscle Thickness and Flexibility

Background: In animal studies long-term stretching interventions up to several hours per day have shown large increases in muscle mass as well as maximal strength. The aim of this study was to investigate the effects of a long-term stretching on maximal strength, muscle cross sectional area (MCSA) and range of motion (ROM) in humans.

Methods: 52 subjects were divided into an Intervention group (IG, n = 27) and a control group (CG, n = 25). IG stretched the plantar flexors for one hour per day for six weeks using an orthosis. Stretching was performed on one leg only to investigate the contralateral force transfer. Maximal isometric strength (MIS) and 1RM were both measured in extended knee joint. Furthermore, we investigated the MCSA of IG in the lateral head of the gastrocnemius (LG) using sonography. Additionally, ROM in the upper ankle was investigated via the functional “knee to wall stretch” test (KtW) and a goniometer device on the orthosis. A two-way ANOVA was performed in data analysis, using the Scheffé Test as post-hoc test.

Results: There were high time-effects (p = 0.003, ƞ² = 0.090) and high interaction-effect (p < 0.001, ƞ²=0.387) for MIS and also high time-effects (p < 0.001, ƞ²=0.193) and interaction-effects (p < 0.001, ƞ²=0,362) for 1RM testing. Furthermore, we measured a significant increase of 15.2% in MCSA of LG with high time-effect (p < 0.001, ƞ²=0.545) and high interaction-effect (p=0.015, ƞ²=0.406). In ROM we found in both tests significant increases up to 27.3% with moderate time-effect (p < 0.001, ƞ²=0.129) and high interaction-effect (p < 0.001, ƞ²=0.199). Additionally, we measured significant contralateral force transfers in maximal strength tests of 11.4% (p < 0.001) in 1RM test and 1.4% (p=0.462) in MIS test. Overall, there we no significant effects in control situations for any parameter (CG and non-intervened leg of IG).

Discussion: We hypothesize stretching-induced muscle damage comparable to effects of mechanical load of strength training, that led to hypertrophy and thus to an increase in maximal strength. Increases in ROM could be attributed to longitudinal hypertrophy effects, e.g., increase in serial sarcomeres. Measured cross-education effects could be explained by central neural adaptations due to stimulation of the stretched muscles.

Adjacent Joint Restriction Differentially Influences Intra- and Inter-rater Reliability and Agreement of Goniometric Measurements

BACKGROUND

Reliability and agreement of goniometric measurements can be altered by variations in measurement technique such as restricting adjacent joints to influence bi-articular muscles. It is unknown if the influence of adjacent joint restriction is consistent across different range of motion (ROM) tests, as this has yet to be assessed within a single study. Additionally, between-study comparisons are challenged by differences between methodology, participants and raters, obscuring the development of a conceptual understanding of the extent to which adjacent joint restriction can influence goniometric ROM measurements.

PURPOSE

To quantify intra- and inter-rater reliability and levels of agreement of goniometric measurements across five ROM tests, with and without adjacent joint restriction.

STUDY DESIGN

Descriptive reliability study.

METHODS

Three trained and experienced raters made two measurements of bilateral ankle dorsiflexion, first metatarsophalangeal dorsiflexion, hip extension, hip flexion, and shoulder flexion, with and without adjacent joint restriction. Intraclass correlation coefficient (ICC), standard error of measurement (SEM), along with participant, measurement/rater and random error variance were estimated.

RESULTS

Eleven females (age 21.4 ±2.3 years) and 19 males (age 22.1 ±2.8 years) participated. Adjacent joint restriction did not influence the reliability and agreement in a consistent way across the five ROM tests. Changes in the inter-rater reliability and agreement were more pronounced compared to the intra-rater reliability and agreement. Assessing variance components (participant, measurement/rater and random error variance) that are used to calculate the ICC and SEM, improved interpretation of ICC and SEM scores.

CONCLUSION

The effects of adjacent joint restriction on reliability and agreement of goniometric measurements depend on the ROM test and should be considered when comparing measurements between multiple raters. Reporting variance components that are used to calculate the ICC and SEM can improve interpretation and may improve between-study comparisons, towards developing a conceptual framework to guide goniometric measurement technique.

LEVEL OF EVIDENCE

3b.

Immediate Effect of Ankle Mobilization on Range of Motion, Dynamic Knee Valgus, and Knee Pain in Women With Patellofemoral Pain and Ankle Dorsiflexion Restriction: A Randomized Controlled Trial With 48-Hour Follow-Up

CONTEXT

Restriction in ankle dorsiflexion range of motion (ROM) has been previously associated with excessive dynamic knee valgus. This, in turn, has been correlated with knee pain in women with patellofemoral pain.

OBJECTIVES

To investigate the immediate effect of 3 ankle mobilization techniques on dorsiflexion ROM, dynamic knee valgus, knee pain, and patient perceptions of improvement in women with patellofemoral pain and ankle dorsiflexion restriction.

DESIGN

Randomized controlled trial with 3 arms.

SETTING

Biomechanics laboratory.

PARTICIPANTS

A total of 117 women with patellofemoral pain who display ankle dorsiflexion restriction were divided into 3 groups: ankle mobilization with anterior tibia glide (n = 39), ankle mobilization with posterior tibia glide (n = 39), and ankle mobilization with anterior and posterior tibia glide (n = 39).

INTERVENTION(S)

The participants received a single session of ankle mobilization with movement technique.

MAIN OUTCOME MEASURES

Dorsiflexion ROM (weight-bearing lunge test), dynamic knee valgus (frontal plane projection angle), knee pain (numeric pain rating scale), and patient perceptions of improvement (global perceived effect scale). The outcome measures were collected at the baseline, immediate postintervention (immediate reassessment), and 48 hours postintervention (48 h reassessment).

RESULTS

There were no significant differences between the 3 treatment groups regarding dorsiflexion ROM and patient perceptions of improvement. Compared with mobilization with anterior and posterior tibia glide, mobilization with anterior tibia glide promoted greater increase in dynamic knee valgus (P = .02) and greater knee pain reduction (P = .02) at immediate reassessment. Also compared with mobilization with anterior and posterior tibia glide, mobilization with posterior tibia glide promoted greater knee pain reduction (P < .01) at immediate reassessment.

CONCLUSION

In our sample, the direction of the tibia glide in ankle mobilization accounted for significant changes only in dynamic knee valgus and knee pain in the immediate reassessment.

Conservative treatment of iliotibial band syndrome in runners: Are we targeting the right goals?

OBJECTIVE

Iliotibial band syndrome (ITBS) is presumably caused by excessive tension in the iliotibial band (ITB) leading to compression and inflammation of tissues lying beneath it. Usually managed conservatively, there is a lack of scientific evidence supporting the treatment recommendations, and high symptom recurrence rates cast doubt on their causal effectiveness. This review discusses the influence of common physiotherapeutic measures on risk factors contributing to tissue compression beneath the ITB.

METHODS

The potential pathogenic factors are presented on the basis of a simple biomechanical model showing the forces acting on the lateral aspect of the knee. Existent literature on the most commonly prescribed physiotherapeutic interventions is critically discussed against the background of this model. Practical recommendations for the optimization of physiotherapy are derived.

RESULTS

According to biomechanical considerations, ITBS may be promoted by anatomical predisposition, joint malalignments, aberrant activation of inserting muscles as well as excessive ITB stiffness. Hip abductor strengthening may correct excessive hip adduction but also increase ITB strain. Intermittent stretching interventions are unlikely to change the ITB's length or mechanical properties. Running retraining is a promising yet understudied intervention.

CONCLUSIONS

High-quality research directly testing different physiotherapeutic treatment approaches in randomized controlled trials is needed.

Effect of Flexibility Training Associated with Multicomponent Training on Posture and Quality of Movement in Physically Inactive Older Women: A Randomized Study

Background: Multicomponent training has considerable adherence among older populations, but there is a lack of literature on the benefits of this training on older people’s posture. Literature also lacks stretching protocols that work the body in an integrated/unified way and respect the principle of individuality in exercise training. We evaluated the effect of a multicomponent training protocol combined or not with flexibility training in improving the posture and quality of movement in physically inactive older women, according to a score lower than 9.11 in the Modified Baecke Questionnaire for the Elderly (MBQE). Methods: 142 participants were evaluated and randomized in three training groups: multicomponent training (MT = 52), multicomponent and flexibility training (MFT = 43), and a control group (CG = 47). We evaluated joint amplitude using goniometry, flexibility with sit and reach and hands behind the back tests, quality of movement with the functional movement screen, and posture using biophotogammetry. Results: The MFT group had 15 parameters—flexibility and posture—with a very large effect size (ES > 1.30) and nine with average ES (0.50–0.79). MT presented two variables with large ES (0.80–1.25) and seven with average ES. CG presented three variables with high ES and five with average ES. Both interventions improved the quality of movement. Conclusions: These results demonstrate that 14 weeks of multicomponent and flexibility training in a group intervention can improve flexibility and posture levels in physically inactive older women.

Serial Within-Session Improvements in Ankle Dorsiflexion During Clinical Interventions Including Mobilization-With-Movement and A Novel Manipulation Intervention - A Case Series

BACKGROUND

Persisting reductions in ankle dorsiflexion range of motion are commonly encountered clinically and seen to be associated with adverse outcomes after ankle and other lower extremity injuries. Accordingly improving identified deficits is a common goal for rehabilitation; however, little data exists documenting any improvement related to interventions in these patients.

PURPOSE

To document the change in dorsiflexion range of motion after stretching and mobilization-with-movement and exercise and a novel manipulation intervention in a population of injured athletes.

DESIGN

Case series in 38 consecutive injured athletes with persisting reductions in ankle dorsiflexion range of motion (42 "stiff" ankles, 34 uninjured) in an outpatient sports physiotherapy clinic.

METHOD

During a single treatment session, two baseline measurements of weight-bearing dorsiflexion were taken at the start of the session to establish reliability and minimum detectable change, and then the same measures were performed after stretching and a mobilization-with-movement intervention, and again after clinical exercise and a novel manipulation which was applied on both ankles.

RESULTS

Excellent reliability was demonstrated (ICC2,1>0.93, MDC=3.5°) for the dorsiflexion measure. Statistically significant (p<0.01), but clinically meaningless improvements were seen after stretching and the mobilization-with-movement intervention on the injured and uninjured legs (1.9° and 1.4° respectively) with greater improvements seen after exercise and the subsequent manipulation (6.9° and 4.7°).

CONCLUSIONS

The relatively simple clinical exercise and manipulation intervention program was associated improvement in dorsiflexion range of motion in this cohort with persisting ankle stiffness. The interventions described largely restored range of motion consistent with baseline levels of the uninjured ankles. Improvements were also seen in the uninjured ankles following intervention.

Increased Ankle Range of Motion Reduces Knee Loads During Landing in Healthy Adults

Decreased dorsiflexion range of motion (DROM) can be modified using static stretching and joint mobilizations and may attenuate known knee anterior cruciate ligament injury risk factors. It is not known how these interventions compare to each other and how they improve knee landing mechanics. This study's purpose was to determine the immediate effects of static stretching and joint mobilization interventions on DROM measurement changes and right-leg drop jump knee landing mechanics. Eighteen females and 7 males, all recreationally active, completed 2 study sessions. Active and passive DROM, the weight-bearing lunge test, the anterior reach portion of the Star Excursion Balance Test, and a right-leg drop jump landing task were completed before and after the intervention. Change in DROM (ΔDROM) was calculated for DROM assessments between preintervention and postintervention. Pairwise dependent t tests determined no differences in ΔDROM between interventions, and statistical parametric mapping determined increased knee flexion (P = .004) and decreased anterior shear force (P = .015) during landing after both interventions. Increased DROM improves sagittal plane displacement and loading at the knee. Stretching may be a more feasible option in a healthy population for those wanting to maintain range of motion and decrease knee injury risk without physical therapist involvement.

The Case for Retiring Flexibility as a Major Component of Physical Fitness

Flexibility refers to the intrinsic properties of body tissues that determine maximal joint range of motion without causing injury. For many years, flexibility has been classified by the American College of Sports Medicine as a major component of physical fitness. The notion flexibility is important for fitness has also led to the idea static stretching should be prescribed to improve flexibility. The current paper proposes flexibility be retired as a major component of physical fitness, and consequently, stretching be de-emphasized as a standard component of exercise prescriptions for most populations. First, I show flexibility has little predictive or concurrent validity with health and performance outcomes (e.g., mortality, falls, occupational performance) in apparently healthy individuals, particularly when viewed in light of the other major components of fitness (i.e., body composition, cardiovascular endurance, muscle endurance, muscle strength). Second, I explain that if flexibility requires improvement, this does not necessitate a prescription of stretching in most populations. Flexibility can be maintained or improved by exercise modalities that cause more robust health benefits than stretching (e.g., resistance training). Retirement of flexibility as a major component of physical fitness will simplify fitness batteries; save time and resources dedicated to flexibility instruction, measurement, and evaluation; and prevent erroneous conclusions about fitness status when interpreting flexibility scores. De-emphasis of stretching in exercise prescriptions will ensure stretching does not negatively impact other exercise and does not take away from time that could be allocated to training activities that have more robust health and performance benefits.

Training and Detraining Effects Following a Static Stretching Program on Medial Gastrocnemius Passive Properties

A stretching intervention program is performed to maintain and improve range of motion (ROM) in sports and rehabilitation settings. However, there is no consensus on the effects of stretching programs on muscle stiffness, likely due to short stretching durations used in each session. Therefore, a longer stretching exercise session may be required to decrease muscle stiffness in the long-term. Moreover, until now, the retention effect (detraining) of such an intervention program is not clear yet. The purpose of this study was to investigate the training (5-week) and detraining effects (5-week) of a high-volume stretching intervention on ankle dorsiflexion ROM (DF ROM) and medial gastrocnemius muscle stiffness. Fifteen males participated in this study and the plantarflexors of the dominant limb were evaluated. Static stretching intervention was performed using a stretching board for 1,800 s at 2 days per week for 5 weeks. DF ROM was assessed, and muscle stiffness was calculated from passive torque and muscle elongation during passive dorsiflexion test. The results showed significant changes in DF ROM and muscle stiffness after the stretching intervention program, but the values returned to baseline after the detraining period. Our results indicate that high-volume stretching intervention (3,600 s per week) may be beneficial for DF ROM and muscle stiffness, but the training effects are dismissed after a detraining period with the same duration of the intervention.

Machine-assisted foot stretching in the elderly: a comparison with self-stretching

[Purpose] Self-stretching is the traditional at-home stretching method of choice. We developed an automatic foot-stretching machine to perform effective dorsiflexion stretching safely and easily at home. The effects of automatic stretching using our machine and self-stretching were investigated and compared. [Participants and Methods] Twelve healthy elderly people participated in the study. Automatic dorsiflexion static stretching was performed with the right foot, and self-stretching using a towel was performed with the left foot. Before and after each stretching, passive range of motion in dorsiflexion, maximal voluntary contraction strength in plantarflexion, passive resistive torque during passive dorsiflexion, and displacement of the muscle-tendon junction of the medial gastrocnemius muscle were measured. [Results] The range of motion in dorsiflexion had a significantly greater increase after automatic stretching than after self-stretching. The maximum strength in plantarflexion tended to decrease after automatic stretching but did not decrease after self-stretching. The passive resistive torque in both types of stretches decreased in some of the participants but increased in others. The displacement of the muscle-tendon junction of the medial gastrocnemius tended to shorten during automatic stretching as compared with self-stretching. [Conclusion] Foot stretching using a machine is as effective as self-stretching and tends to affect the tendon rather than the muscle.

Reliability of isokinetic tests of velocity- and contraction intensity-dependent plantar flexor mechanical properties

"Flexibility" tests are traditionally performed voluntarily relaxed by rotating a joint slowly; however, functional activities are performed rapidly with voluntary/reflexive muscle activity. Here, we describe the reliabilities and differences in maximum ankle range of motion (ROM_max ) and plantar flexor mechanical properties at several velocities and levels of voluntary force from a new test protocol on a commercially available dynamometer. Fifteen participants had their ankle joint dorsiflexed at 5, 30, and 60° s^-1 in two conditions: voluntarily relaxed and while producing 40% and 60% of maximal eccentric torque. Commonly reported variables describing ROM_max and resistance to stretch were subsequently calculated from torque and angle data. Absolute (coefficient of variation (CV%) and typical error) and relative (ICC_2,1 ) reliabilities were determined across two testing days (≥72 h). ROM_max relative reliability was good in voluntarily relaxed tests at 30 and 60° s^-1 and moderate at 5° s^-1 , despite CVs ≤ 10% for all velocities. Tests performed with voluntary muscle activity were only reliable when performed at 5° s^-1 , and ROM_max reliability was moderate and CV ≤ 8%. For most variables, the rank order of participants differed between the slow-velocity, relaxed test, and those performed at faster speeds or with voluntary activation, indicating different information. A person's flexibility status during voluntarily relaxed fast or active stretches tended to differ from their status in the traditional voluntarily relaxed, slow-velocity test. Thus, "flexibility" tests should be completed under conditions of different stretch velocity and levels of muscle force production, and clinicians and researchers should consider the slightly larger between-day variability from slow-velocity voluntarily relaxed tests.

Effect of a HIIT protocol on the lower limb muscle power, ankle dorsiflexion and dynamic balance in a sedentary type 1 diabetes mellitus population: a pilot study

Background

Type 1 diabetes mellitus (T1DM) is commonly associated with premature loss of muscle function, ankle dorsiflexion and dynamic balance. Those impairments, usually, lead to physical functionality deterioration. High-intensity interval training is an efficient and safety methodology since it prevents hypoglycemia and not requires much time, which are the main barriers for this population to practice exercise and increase physical conditioning. We hypothesized that a 6-week HIIT program performed on a cycle ergometer would increase lower limb muscle power, ankle dorsiflexion range of motion and dynamic balance without hypoglycemic situations.

Methods

A total of 19 diagnosed T1DM subjects were randomly assigned to HIIT group (n = 11; 6-week HIIT protocol) or Control group (n = 8; no treatment). Lower limb strength was evaluated through velocity execution in squat with three different overloads. Weight bearing lunge test (WBLT) was performed to test ankle dorsiflexion range of motion and Y-Balance test (YBT) was the test conducted to analyze dynamic balance performance.

Results

Velocity in squat improved a 11.3%, 9.4% and 10.1% (p < 0.05) with the 50%, 60% and 70% of their own body mass overload respectively, WBLT performance increased a 10.43% in the right limb and 15.45% in the left limb. YBT showed improvements in all directions (right limb-left limb): Anterior (4.3–6.1%), Posteromedial (1.8–5.2%) and Posterolateral (3.4–4.5%) in HIIT group (p < 0.05), unlike control group that did not experience any significant change in any of the variables (p > 0.05).

Conclusion

A 6-week HIIT program is safe and effective to improve execution velocity in squat movement, a fundamental skill in daily living activities, as well as ankle dorsiflexion range of motion and dynamic balance to reduce foot ulcers, risk falls and functional impairments. HIIT seems an efficient and safety training methodology not only for overcome T1DM barriers for exercising but also for improving functional capacities in T1DM people.

Static Ankle Dorsiflexion and Hip and Pelvis Kinematics During Forward Step-Down in Patients With Hip-Related Groin Pain

CONTEXT

The authors hypothesized that in people with hip-related groin pain, less static ankle dorsiflexion could lead to compensatory hip adduction and contralateral pelvic drop during step-down. Ankle dorsiflexion may be a modifiable factor to improve ability in those with hip-related groin pain to decrease hip/pelvic motion during functional tasks and improve function.

OBJECTIVE

To determine whether smaller static ankle dorsiflexion angles were associated with altered ankle, hip, and pelvis kinematics during step-down in people with hip-related groin pain.

DESIGN

Cross-sectional Setting: Academic medical center.

PATIENTS

A total of 30 people with hip-related groin pain (12 males and 18 females; 28.7 [5.3] y) participated.

INTERVENTION

None.

MAIN OUTCOME MEASURES

Weight-bearing static ankle dorsiflexion with knee flexed and knee extended were measured via digital inclinometer. Pelvis, hip, and ankle kinematics during forward step-down were measured via 3D motion capture. Static ankle dorsiflexion and kinematics were compared with bivariate correlations.

RESULTS

Smaller static ankle dorsiflexion angles were associated with smaller ankle dorsiflexion angles during the step-down for both the knee flexed and knee extended static measures. Among the total sample, smaller static ankle dorsiflexion angle with knee flexed was associated with greater anterior pelvic tilt and greater contralateral pelvic drop during the step-down. Among only those who did not require a lowered step for safety, smaller static ankle dorsiflexion angles with knee flexed and knee extended were associated with greater anterior pelvic tilt, greater contralateral pelvic drop, and greater hip flexion.

CONCLUSIONS

Among those with hip-related groin pain, smaller static ankle dorsiflexion angles are associated with less ankle dorsiflexion motion and altered pelvis and hip kinematics during a step-down. Future research is needed to assess the effect of treating restricted ankle dorsiflexion on quality of motion and symptoms in patients with hip-related groin pain.

Effects of different stretching methods on vertical jump ability and range of motion in young female artistic gymnastics athletes

BACKGROUND

Female artistic gymnastics includes multiple athletic gestures that can be performed by combining jump strength with wide degrees of joint mobility. The purpose of this study was to examine the effects of two different types of stretching on vertical jump height and range of motion in competitive gymnasts and to identify the most suitable stretching protocol for increasing range of motion, without negatively affecting vertical jump performance.

METHODS

In a crossover design, following dynamic stretching, static stretching, and control (no stretching), eight competitive female gymnasts (age: 14±2 years; BMI: 18.8±1.4 kg/m², mean±SD) were tested on jump performance through a squat jump, a countermovement jump and an acrobatic gymnastic jump, and on range of motion by measuring the amplitude of the forward oversplit figure.

RESULTS

One-way repeated measure ANOVA revealed significant main, very large effect of stretching condition (P<0.01). Post-hoc comparisons showed improvement of squat jump and countermovement jump after dynamic stretching with respect to static stretching and control (P<0.05). Range of motion increased significantly following static stretching with respect to dynamic stretching and control (P<0.01).

CONCLUSIONS

Dynamic stretching is recommended in the warm-up to increase vertical jump performance, while specific static stretching should be pursued in the final phase of the training session being a specific technical work for range of motion.

Changes of Ankle Dorsiflexion Using Compression Tissue Flossing: A Systematic Review and Meta-Analysis

CONTEXT

Impaired dorsiflexion range of motion (DFROM) has been established as a predictor of lower-extremity injury. Compression tissue flossing (CTF) may address tissue restrictions associated with impaired DFROM; however, a consensus is yet to support these effects.

OBJECTIVES

To summarize the available literature regarding CTF on DFROM in physically active individuals.

EVIDENCE ACQUISITION

PubMed and EBSCOhost (CINAHL, MEDLINE, and SPORTDiscus) were searched from 1965 to July 2019 for related articles using combination terms related to CTF and DRFOM. Articles were included if they measured the immediate effects of CTF on DFROM. Methodological quality was assessed using the Physiotherapy Evidence Database scale. The level of evidence was assessed using the Strength of Recommendation Taxonomy. The magnitude of CTF effects from pre-CTF to post-CTF and compared with a control of range of motion activities only were examined using Hedges g effect sizes and 95% confidence intervals. Randomeffects meta-analysis was performed to synthesize DFROM changes.

EVIDENCE SYNTHESIS

A total of 6 studies were included in the analysis. The average Physiotherapy Evidence Database score was 60% (range = 30%-80%) with 4 out of 6 studies considered high quality and 2 as low quality. Meta-analysis indicated no DFROM improvements for CTF compared with range of motion activities only (effect size = 0.124; 95% confidence interval, -0.137 to 0.384; P = .352) and moderate improvements from pre-CTF to post-CTF (effect size = 0.455; 95% confidence interval, 0.022 to 0.889; P = .040).

CONCLUSIONS

There is grade B evidence to suggest CTF may have no effect on DFROM when compared with a control of range of motion activities only and results in moderate improvements from pre-CTF to post-CTF. This suggests that DFROM improvements were most likely due to exercises completed rather than the band application.

The optimal duration of high-intensity static stretching in hamstrings

Objectives

The purpose of this study was to compare the duration of high-intensity static stretching on flexibility and strength in the hamstrings.

Methods

Fourteen healthy males (20.8 ± 0.6 years, 170.7 ± 6.5 cm, 66.4 ± 9.9 kg) underwent high-intensity static stretching for three different durations (10, 15, and 20 seconds). The intensity of static stretching was set at the maximum point of discomfort. To examine the change in flexibility and strength, range of motion, peak passive torque, relative passive torque, muscle-tendon unit stiffness, peak torque of isokinetic knee flexion, and knee angle at peak torque of isokinetic knee flexion were measured. To evaluate a time course of pain, a numerical rating scale was described.

Results

Range of motion (P < 0.01), peak passive torque (P < 0.01), and knee angle at peak torque were increased at all interventions. Relative passive torque (P < 0.01) and muscle-tendon unit stiffness (P < 0.01) were decreased at all interventions. Peak torque decreased after 10 seconds of stretching (P < 0.05). Numerical rating scale during stretching was 8–9 levels in all interventions, the pain disappeared immediately after the post-measurements (median = 0).

Conclusion

The results suggested that muscle-tendon unit stiffness decreased regardless of duration of high-intensity static stretching. However, peak torque of isokinetic knee flexion decreased after 10 seconds of high-intensity static stretching, though it was no change after for more than 15 seconds of stretching.

Principal motion analysis of manual stretching techniques for the ankle joints

[Purpose] Physical therapists frequently perform manual stretching of the ankle joints. Manual stretching procedures are challenging to define because they involve multidirectional joint motions and external forces. Therefore, in this paper, we propose a method for quantitatively and statistically analyzing the manual foot stretching techniques used by physical therapists. [Participants and Methods] The participants were four physical therapists, and three patients who have a spastic foot. We investigated the manual foot stretching techniques employed by the physical therapists using a three-dimensional analysis system and an instrumented brace with force sensors. Principal motion analysis was applied to the obtained data, and principal motions were determined. [Results] The first principal motion was the application of force for the dorsiflexion of the foot; second, the pushing/pulling of the heel; third, the eversion/inversion of the entire foot; and fourth, the eversion/inversion of the forefoot. Furthermore, the manual stretching techniques varied among the physical therapists, even for the same patient, and some techniques occurred only between particular pairs. [Conclusion] This study demonstrated the effectiveness of the principal motion analysis for the statistical assessment of manual stretching techniques and clarifying differences in stretching technique among physical therapists.

Ankle flossing alters periarticular stiffness and arterial blood flow in asymptomatic athletes

BACKGROUND

Tissue flossing has been introduced to increase impaired range of motion (ROM) and flexibility, to enhance prevention and rehabilitation, as well as to improve athletic performance; however, limited evidence exists for its efficacy. The aim of the present study was to evaluate the effects of ankle flossing on periarticular stiffness and perfusion via Acoustic Radiation Force Impulse (ARFI) elastography and Power Doppler Sonography (PDS).

METHODS

Twenty-one healthy students (age: 24±2 years, BMI: 22±3 kg/m²) were recruited as participants. ARFI was performed to evaluate periarticular ankle stiffness involving the anterior ankle capsule (AC), the anterior talofibular ligament (ATFL) and the peroneus brevis muscle (PBM). Arterial blood flow was assessed in the dorsal pedal artery. Measurements were taken under resting conditions (T<inf>0</inf>) and twice after standardized ankle flossing (T<inf>1</inf>: 0 min., T<inf>2</inf>: 60 min. postintervention).

RESULTS

The connective tissue stiffness decreased significantly after ankle flossing compared to baseline (T<inf>1</inf>, AC: -12%, P=0.009, ATFL: -12%, P=0.003; T<inf>2</inf>, AC: -8%, P=0.002, ATFL: -9%, P=0.015). The PBM stiffness decreased by 3% (T<inf>1</inf>, P=0.304) and 4% (T<inf>2</inf>, P=0.029). The perfusion measures significantly increased by 30% at T<inf>1</inf> compared to baseline (P=0.001); no significant changes were observed at T<inf>2</inf> (P=0.492).

CONCLUSIONS

This is the first study demonstrating decreased AC and ATFL stiffness and reactive hyperemia to be key mechanisms of ankle flossing. Additional studies must be conducted to determine whether changes in biomechanical properties influence dynamic ankle stability.

Effects of static stretching programs performed at different volume-equated weekly frequencies on passive properties of muscle-tendon unit

Whether static stretching (SS) frequency has an effect on increasing the range of motion (ROM) and decreasing muscle stiffness remains unclear. Therefore, this study aimed to investigate the effects of two 6-week SS programs performed with different frequencies but generally the same duration of stretching on the passive properties of the medial gastrocnemius muscle-tendon unit. The study participants comprised 24 male volunteers randomly assigned to either the one-time/week group or the three-times/week group, performing 6 min of SS once per week and 2 min of SS thrice per week, respectively. The dorsiflexion ROM (DF ROM) and muscle stiffness of the medial gastrocnemius during passive ankle dorsiflexion were assessed using a dynamometer and ultrasonography before and after 6 weeks of SS programs. The results show that the DF ROM was increased and muscle stiffness was decreased significantly in the three-times/week group (P < 0.01 and P < 0.01, respectively), whereas no significant changes were observed in DF ROM and muscle stiffness in the one-time per week group (P = 0.25 and P = 0.32, respectively). These results suggest that a high-frequency SS program is more effective than a low-frequency SS program in increasing ROM and decreasing muscle stiffness.

Hindfoot endoscopic release of the posterior ankle capsuloligamentous structures improves ankle dorsiflexion range, function and pain in patients with painful limitation of ankle dorsiflexion

Objective

To evaluate the effect of arthroscopic release of the posterior capsuloligamentous structures on ankle dorsiflexion and function in patients with painful limitation of ankle dorsiflexion.

Methods

A prospective consecutive case series of 13 adult patients with painful limitation of ankle dorsiflexion were included. None had clinically relevant gastrocnemius, soleus or Achilles contracture. Patients with anterior bony impingement or ankle degeneration on CT scan were excluded. All patients underwent combined anterior and posterior ankle arthroscopies with resection of posterior capsuloligamentous structures and the posterior fibulotalocalcaneal ligament. Ankle range of motion was assessed 2 years postoperatively. Foot and Ankle Outcome Scores (FAOS) were used to assess functional outcome.

Results

The median patient age at surgery was 26 years (range 19–44). At 2 years postsurgery, the ankle dorsiflexion range had increased by 15 degrees (range 0–25, p<0.0001). FAOSs completed at a median of 44 months postsurgery (range 26–72) significantly improved. Median improvements were 19 points for pain (range 6–67, p=0.0004), 14 points for symptoms (range 0–36, p=0.0005), 15 points for activities of daily living (range 6–35, p<0.0001), 45 points for sport (range 20–55, p<0.0001) and 50 points for quality of life (range 13–62, p<0.0001).

Conclusions

Hindfoot endoscopic release of the posterior ankle structures, including the posterior fibulotalocalcaneal ligament, is an effective technique for improving ankle dorsiflexion range in patients with painful limitation of ankle dorsiflexion.

Level of evidence

IV.

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

Static stretching (SS) has been used for inducing acute and long-term increases in range of motion (ROM). Foam rolling (FR) has recently gained popularity for acutely increasing ROM. However, the long-term effects of FR on ROM have not been thoroughly evaluated. Therefore, the purpose of this study was to investigate the acute and long-term changes in dorsiflexion ROM as a result of 6 wk of FR, SS, and FR followed by SS (FR + SS).

METHODS

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.

RESULTS

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).

CONCLUSION

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.

Neurodynamic sliders promote flexibility in tight hamstring syndrome

ABSTRACT Hamstring injury prevention puts emphasis on optimizing the muscle's strength-length relationship. To assure appropriate muscle length, flexibility training is imperative. As neurodynamics play an important role herein, the goal of this study was to explore the intervention effect of home-based neurodynamic slider program on hamstring flexibility. Fifty physically active male subjects were randomly assigned to either performing a neurodynamic sliding technique (3 × 20 reps) or a static stretching protocol (3 × 30″) on a daily basis for a 6-week period. Hamstring flexibility was assessed by means of the Straight Leg Raise at baseline, immediately after the intervention and after 4 weeks follow up. There was no between group baseline difference in hamstring flexibility. The repeated measure ANOVA showed a significant interaction effect for group × time (p < 0.001). Independent sample t-test showed a significantly higher increase in flexibility gain in the neurodynamic group immediately after the intervention (p < 0.001), as well as at 4 weeks retention analysis (p = 0.001) compared to the static stretch group. In conclusion, neurodynamic sliders might be more efficient than regular static stretching in affecting hamstring flexibility in the long run.

Muscle stretching changes neuromuscular function involved in ankle stability

It has been postulated that the mechanical and neurophysiological effects induced by stretching decrease maximal muscle strength and power. Additionally, the reduction in neural input and muscle stiffness can affect the joint stabilization process. However, there is no evidence available to support this hypothesis. Thus, the aim of this study is to analyze the influence of static stretching on dynamic joint stability. Twenty physically active female university students (22.8 ± 5.3 years; 58 ± 8.8 kg; 1.62 ± 0.07 m) performed a series of static-passive stretching exercises for the peroneus longus and brevis muscles (four repetitions of 30 s). Before and after the stretches, electromyography was performed on both muscles during simulated ankle sprain. Mathematical algorithms calculate the latency and the electromyography activity (RMS). After stretching, the latency increased from 66ms to 73 ms (p = 0.003) for the peroneus brevis muscle and from 70 ms to 79 ms (p = 0.001) for the peroneus longus muscle. The RMS, calculated 100 ms after the simulation, decreased in the peroneus brevis muscle, from 25.05 to 18.16 (p = 0.001), and in the peroneus longus muscle, from 22.84 to 15.61 (p = 0.001). Muscle stretching changed the motor responses of both muscles. The increase in latency and the decrease in RMS indicate that static stretching influences the neuromuscular function involved in the joint stabilization process.