Effectiveness of a Posterior Shoulder Stretching Program on University-Level Overhead Athletes: Randomized Controlled Trial

Optimising the Dose of Static Stretching to Improve Flexibility: A Systematic Review, Meta-analysis and Multivariate Meta-regression

BACKGROUND

Static stretching is widely used to increase flexibility. However, there is no consensus regarding the optimal dosage parameters for increasing flexibility.

OBJECTIVES

We aimed to determine the optimal frequency, intensity and volume to maximise flexibility through static stretching, and to investigate whether this is moderated by muscle group, age, sex, training status and baseline level of flexibility.

METHODS

Seven databases (CINAHL Complete, Cochrane CENTRAL, Embase, Emcare, MEDLINE, Scopus, and SPORTDiscus) were systematically searched up to June 2024. Randomised and non-randomised controlled trials investigating the effects of a single session (acute) or multiple sessions (chronic) of static stretching on one or more flexibility outcomes (compared to non-stretching passive controls) among adults (aged ≥ 18 years) were included. A multi-level meta-analysis examined the effect of acute and chronic static stretching on flexibility outcomes, while multivariate meta-regression was used to determine the volume at which increases in flexibility were maximised.

RESULTS

Data from 189 studies representing 6654 adults (61% male; mean [standard deviation] age = 26.8 ± 11.4 years) were included. We found a moderate positive effect of acute static stretching on flexibility (summary Hedges' g = 0.63, 95% confidence interval 0.52-0.75, p < 0.001) and a large positive effect of chronic static stretching on flexibility (summary Hedges' g = 0.96, 95% confidence interval 0.84-1.09, p < 0.001). Neither effect was moderated by stretching intensity, age, sex or training status, or weekly session frequency and intervention length (chronic static stretching only) [p > 0.05]. However, larger improvements were found for adults with poor baseline flexibility compared with adults with average baseline flexibility (p = 0.01). Furthermore, larger improvements in flexibility were found in the hamstrings compared with the spine following acute static stretching (p = 0.04). Improvements in flexibility were maximised by a cumulative stretching volume of 4 min per session (acute) and 10 min per week (chronic).

CONCLUSIONS

Static stretching improves flexibility in adults, with no additional benefit observed beyond 4 min per session or 10 min per week. Although intensity, frequency, age, sex and training status do not influence improvements in flexibility, lower flexibility levels are associated with greater improvement following both acute and chronic static stretching. These guidelines for static stretching can be used by coaches and therapists to improve flexibility.

CLINICAL TRIAL REGISTRATION

PROSPERO CRD42023420168.

Electromyographic activity of shoulder muscles on two preventive exercise programmes for swimmer's shoulder: elastic band versus weight

Strength programmes have shown good results in preventing swimmer's shoulder. However, there aren't studies based on electromyographic (EMG) analysis in these programmes. This study aims to compare an EMG activity of the middle trapezius (MT), lower trapezius (LT), infraspinatus (IS), serratus anterior (SA), and pectoralis major (PM) in two swimmer's shoulder preventive programmes - one performed with elastic band and the other with weights. Twenty competitive swimmers performed two strength programmes consisting of five exercises each, while the analysis of EMG activity in MT, LT, IS, SA, and PM for each exercise was recorded. The superficial EMG was used to collect data at a sampling frequency of 1000 hz. The Paired Sample T-test or the Wilcoxon test was applied to compare EMG activity between programmes. The internal rotation at 90º (p < 0.001) and external rotation at 90º (p ≤ 0.01) exercises produced high myoelectric shoulder muscle activity with an elastic band. Conversely, scapular punches (p < 0.001) exercise has high shoulder EMG activity when performed with weights. Performing the same preventive exercise programme with two different instruments produces great variability in the myoelectric activity of the shoulder muscles.

Static Stretch Training versus Foam Rolling Training Effects on Range of Motion: A Systematic Review and Meta-Analysis

BACKGROUND

Long-term static stretching as well as foam rolling training can increase a joint's range of motion (ROM). However, to date, it is not clear which method is the most effective for increasing ROM.

OBJECTIVE

The purpose of this systematic review and meta-analysis was to compare the effects of static stretching and foam rolling training on ROM.

METHODS

The literature search was performed in PubMed, Scopus, and Web of Science to find the eligible studies. Eighty-five studies (72 on static stretching; and 13 on foam rolling) were found to be eligible with 204 effect sizes (ESs). For the main analyses, a random-effect meta-analysis was applied. To assess the difference between static stretching and foam rolling, subgroup analyses with a mixed-effect model were applied. Moderating variables were sex, total intervention duration, and weeks of intervention.

RESULTS

Static stretch (ES =  - 1.006; p < 0.001), as well as foam rolling training (ES =  - 0.729; p = 0.001), can increase joint ROM with a moderate magnitude compared with a control condition. However, we did not detect a significant difference between the two conditions in the subgroup analysis (p = 0.228). When the intervention duration was ≤ 4 weeks, however, a significant change in ROM was shown following static stretching (ES =  - 1.436; p < 0.001), but not following foam rolling (ES =  - 0.229; p = 0.248). Thus, a subgroup analysis indicated a significant favorable effect with static stretching for increasing ROM compared with foam rolling (p < 0.001) over a shorter term (≤ 4 weeks). Other moderator analyses showed no significant difference between static stretch and foam rolling training on ROM.

CONCLUSIONS

According to the results, both static stretching and foam rolling training can be similarly recommended to increase joint ROM, unless the training is scheduled for ≤ 4 weeks, in which case static stretching demonstrates a significant advantage. More studies are needed with a high-volume foam rolling training approach as well as foam rolling training in exclusively female participants.

An evidence-informed rehabilitation management framework for posterior shoulder tightness: A scoping review

Objective

To systematically scope the literature on posterior shoulder tightness (PST) and define a therapist-instructed and therapist-administered management framework.

Design

Scoping review.

Literature search

We searched MEDLINE, EMBASE, CINAHL, Scopus and Google Scholar from inception to December 2021.

Study selection criteria

Peer-reviewed studies written in English, French, Greek, Japanese or Tamil, with extractable pre- and post-intervention data. Physiotherapy interventions amenable for posterior shoulder structural (muscle, capsule) causes of PST within an adult population.

Data synthesis

Arksey and O'Malley's framework was implemented and the PRISMA extension for scoping reviews directed our data synthesis. The data charted from each study included authors, title, study year, location, study design; participant number, age, sex; PST intervention and parameters; patient-reported outcomes; and results. Themes were organized into therapist-instructed and therapist-administered rehabilitation strategies, as well as combined treatment methods.

Results

Of 2777 articles identified from our search strategy, 21 articles were included. Therapist-instructed interventions included cross-body stretch (CBS), sleeper stretch (SS), a combination of the two and general stretching. Therapist-administered interventions included CBS, SS, instrument-assisted soft tissue mobilization (IASTM), muscle energy techniques, dry needling and Fauls protocol (12 therapist-assisted stretches). Combined interventions of tape with self-stretching and IASTM and stretching were also identified.

Conclusion

Based on the current evidence, CBS and SS are the most researched treatments for PST and seem to be effective at improving PST. Furthermore, stabilization of the scapula while performing these stretches optimized the stretch targeted to the PST and ROM benefits for horizontal adduction.

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.

Efficacy of Conservative Therapy in Overhead Athletes with Glenohumeral Internal Rotation Deficit: A Systematic Review and Meta-Analysis

BACKGROUND

To evaluate the effectiveness of conservative therapy in range of movement (ROM), strength, pain, subacromial space and physical function, in overhead athletes with glenohumeral internal rotation deficit (GIRD).

METHODS

A systematic review and meta-analysis was designed, and the protocol was registered in PROSPERO (CRD42021281559). The databases searched were: PubMed, Cochrane Central Register of Controlled Trials, Physiotherapy Evidence Database, Web of Science and SCOPUS. Randomized controlled trials (RCTs) involving conservative therapy applied in overhead athletes with GIRD were included. Two independent assessors evaluated the quality of the studies with the PEDro scale, and with the Cochrane Risk-of-Bias tool. The overall quality of the evidence was assessed using GRADE. Data on outcomes of interest were extracted by a researcher using RevMan 5.4 software. Estimates were presented as standardized mean differences (SMD) with 95% confidence intervals (CIs).

RESULTS

A total of eleven studies involving 514 overhead athletes were included in the systematic review; of these 8 were included in the meta-analysis. The methodological quality of the included RCTs ranged from high to low. Conservative therapy showed significant improvements in internal rotation, adduction, physical function and subacromial space.

CONCLUSIONS

Conservative therapy based on stretch, passive joint and muscular mobilizations can be useful to improve the internal rotation and adduction ROM, subacromial space, and physical function of the shoulder in overhead athletes with glenohumeral internal rotation deficit.

Number of Months of Baseball in the Previous Year and Preseason Olecranon Tenderness: Risk Factors for Shoulder and Elbow Injuries in High-School Baseball Players

OBJECTIVE

To identify risk factors for shoulder and elbow injuries in high-school baseball position players and pitchers in the preseason history and physical examination.

DESIGN

Retrospective cohort study.

SETTING

Community high-school baseball.

PARTICIPANTS

Three hundred seventy-one male baseball players' mean age 15.0 ± 1.8 years.

OUTCOME MEASURES

A preseason history and physical examination was performed on all athletes. Injury information was collected by weekly self-report and athletic trainer injury logs throughout the season. Comparisons between injured and noninjured players were performed using t tests and χ 2 analyses. Binary logistic regression models were developed to identify risk factors for injury.

RESULTS

Seventy-six injuries were recorded over the season. In univariate analysis, the injured group had greater months of baseball participation ( P = 0.007) and shoulder visual analog scale for the past year ( P = 0.003). The injured group also had more olecranon tenderness ( P < 0.0001, odds ratio [OR] 2.9) and decreased elbow arc of motion. All other factors were not significantly different ( P > 0.05). In multivariable logistic regression, months per year of baseball participation was the only factor significantly associated with injuries ( P = 0.010, OR = 1.21).

CONCLUSIONS

Baseball players who developed arm injuries during a season were more likely to play more months of baseball and report shoulder pain in the previous year. The presence of preseason olecranon tenderness was associated with nearly triple the risk of injury during the season. Every additional month of baseball participation in the previous year was associated with a 1.2× increased odds of injury. The presence of glenohumeral internal rotation deficit was not a predictor of injury.

Effectiveness of Therapeutic Exercise in Musculoskeletal Risk Factors Related to Swimmer's Shoulder

BACKGROUND

Therapeutic exercise seems to minimize musculoskeletal risk factors related to swimmer's shoulder. However, there is an absence of a qualitative evaluation of these programs and a great variability regarding the characteristics of exercises. The objective of this review was to identify, evaluate, and compare exercise programs used to minimize musculoskeletal risk factors related to swimmer's shoulder.

METHODS

PubMed, CochraneLibrary, ScienceDirect, and Medscape were searched during January 2022. The research was limited to meta-analyses, systematic reviews, and RCTs written in English, Spanish, and Portuguese without publication time. The researched papers had swimmers as the population, compared an exercise program with another program or without intervention, and had as outcomes musculoskeletal risk factor variables.

RESULTS

Eleven articles were considered for analysis. There were three positive effects of strength programs on shoulder rotators' strength and endurance, two positive effects of strength and stretching programs on shoulder posture, and one positive effect of a stretching program on shoulder ROM and a plyometric program on proprioception.

CONCLUSIONS

There is high heterogeneity and little methodological quality evidence about the theme. However, strength programs with five or fewer OKC exercises performed out of the water seems to lead to better results in the swimmer's shoulder prevention.

Evaluation of the inter and intraobserver reproducibility of the GRASP method: a goniometric method to measure the isolated glenohumeral range of motion in the shoulder joint

Purpose

To evaluate the intra and interobserver reproducibility of a new goniometric method for evaluating the isolated passive range of motion of the glenohumeral joint in an outpatient setting.

Methods

This is a prospective observational study on healthy subjects. The Glenohumeral ROM Assessment with Scapular Pinch (GRASP) method is a new method for assessing the isolated range of motion (ROM) of the glenohumeral joint (GH) by a single examiner with a clinical goniometer. It measures the isolated glenohumeral passive abduction (GH-AB), passive external rotation (GH-ER) and internal rotation (GH-IR) with the arm at 45º of abduction.

These three GH ROM parameters were measured in both shoulders of 30 healthy volunteers (15 males/15 females, mean age:41.6[SD = 10.3] years). The full shoulder passive abduction, passive external rotation and internal rotation 45º of abduction were measured by the same examiners with a goniometer for comparison. One examiner made two evaluations and a second examiner made a third one. The primary outcome was the intra- and interobserver reproducibility of the measurements assessed with intraclass correlation coefficients (ICC) and the Bland–Altman plot.

Results

The intra-observer ICC for isolated glenohumeral ROM were: 0.84 ± 0.07 for GH-ABD, 0.63 ± 0.09 for GH-ER, and 0.61 ± 0.14 for GH-IR. The inter-observer ICC for isolated glenohumeral ROM were: 0.86 ± 0.06 for GH-ABD, 0.68 ± 0.12 for GH-ER, and 0.62 ± 0.14 for GH-IR. These results were similar to those obtained for full shoulder ROM assessment with a goniometer.

Conclusion

The GRASP method is reproducible for quick assessment of isolated glenohumeral ROM.

Level of evidence

III

Supplementary Information

The online version contains supplementary material available at 10.1186/s40634-021-00352-z.

Pragmatic posterior capsular stretch and its effects on shoulder joint range of motion

OBJECTIVE

To evaluate the immediate effects of pragmatic posterior capsular stretch (PPCS) on shoulder joint range of motion (ROM).

METHOD

A quasi-experimental design was used to recruit healthy subjects of age 21.43 (±1.960) years, height 165.8 (±2.1069) cm and weight 63.90 (±13.187) kg. Inclusion criteria were grade 1 and grade 2 of the shoulder mobility test of functional movement screening. Preintervention and postintervention measurement of flexion, abduction, internal rotation (IR), external rotation (ER), reaching up behind the back (RUBTB) and reaching down behind the neck (RDBTN) were compared. A therapist-administered PPCS was the only intervention applied.

RESULTS

Paired t-test statistics showed improvement (mean°±SD) in shoulder flexion (13.5°±8.11), abduction (11°±8.35), IR (8.5°±10.27), ER (7.83°±7.15), RUBTB (17.34°±13.81) inches and RDBTN (2.93±1.52) inches. The changes in these ROM and functional movements were statistically significant (p<0.05).

CONCLUSION

PPCS can effectively improve the functional movement of RUBTB and shoulder ROM in healthy subjects. It is recommended for the trials on prevention and rehabilitation of shoulder pathologies.

TRIAL REGISTRATION NUMBER

NCT04242888.

Does an effective shoulder injury prevention program affect risk factors in handball? A randomized controlled study

BACKGROUND

Shoulder problems are common in handball, but injury risk reduction is possible by implementing a prevention program. However, player compliance to the program remains a challenge, with feedback from players that the program is too time consuming.

AIM

To develop a more efficient program, we aimed to assess the effect of the Oslo Sports Trauma Research Center shoulder injury prevention program on external rotation (ER) strength and internal rotation (IR) range of motion (ROM), considered to represent key risk factors for injury.

METHODS

Four youth handball teams (three females, one males, 57 players, mean age 17.1 years) were randomized to an intervention or control group. The intervention program was conducted three times per week as a part of handball warm-up for 18 weeks, supervised by physical therapists. The main outcome variables were the between-group differences in ER strength and IR ROM change from baseline to postintervention. Isometric ER strength was measured with a handheld dynamometer and IR ROM with a digital goniometer.

RESULTS

Mean dominant shoulder isometric ER strength increased both in the intervention (10%) and the control group (6%) during the intervention, but there was no significant group by time interaction (group difference: 0.06 N/kg (95% CI: -0.04 to 0.17). IR ROM did not change in either group during the intervention.

CONCLUSION

The Oslo Sports Trauma Research Center shoulder injury prevention program did not affect the risk factors ER strength and IR ROM. The preventive effect of the program must therefore be due to other factors.

Effects of Modified Posterior Shoulder Stretching Exercises on Shoulder Mobility, Pain, and Dysfunction in Patients With Subacromial Impingement Syndrome

BACKGROUND

Posterior shoulder stretching exercises (PSSEs) aim to reduce posterior shoulder tightness (PST). Position modification of traditional PSSEs has been suggested to minimize inadequate control of scapular and glenohumeral rotation, possibly leading to increased subacromial impingement.

HYPOTHESIS

Modified PSSEs will have positive effects on shoulder mobility, pain, and dysfunction.

STUDY DESIGN

Randomized controlled trial.

LEVEL OF EVIDENCE

Level 1.

METHODS

A total of 67 symptomatic patients with subacromial impingement syndrome (SIS) and shoulder internal rotation asymmetry were randomly assigned to 3 groups: modified cross-body stretch (MCS) (n = 22; treatment program + MCS), modified sleeper stretch (MSS) (n = 22; treatment program + MSS), and a control group (n = 23; treatment program consisting of only modalities, range of motion [ROM], and strength training but no PSSEs) for 4 weeks. Pain, PST, shoulder rotation ROM, and dysfunction were evaluated.

RESULTS

Pain, PST, shoulder rotation ROM, function, and disability improved in all groups (P < 0.05). The MCS and MSS groups had better results compared with the control group with regard to pain with activity, internal rotation ROM, function, and disability (P < 0.05). There was no significant difference between the stretching groups (P > 0.05).

CONCLUSION

All treatments improved pain, shoulder mobility, function, and disability in patients with SIS. However, modified PSSEs in addition to a treatment program was superior to the treatment program alone (without PSSEs) in improving pain with activity, internal rotation ROM, and dysfunction. Moreover, stretching provided clinically significant improvements.

CLINICAL RELEVANCE

Modified PSSEs, in addition to a treatment program, are beneficial for patients with SIS. Both modified cross-body and sleeper stretches are safe and efficacious for improving shoulder mobility, pain, and dysfunction.