Risk Factors for Shoulder Injuries in Female Athletes Playing Overhead Sports: A Systematic Review

CONTEXT

Sports involving overhead motions put substantial biomechanical demands on the shoulder and may result in injuries.

OBJECTIVE

To determine risk factors (RFs) for shoulder injuries in female athletes who play overhead sports and evaluate strategies to reduce shoulder injuries in these athletes.

DATA SOURCES

A systematic electronic search was performed according to Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines. Databases included were PubMed, Tulane Matas Library Search Engine, and Google Scholar, with search terms: "Overhead injuries/Shoulder AND female athletes AND Risk Factors."

STUDY SELECTION

Of the initial 1574 studies identified, 314 were evaluated for eligibility by full-text review and 291 studies were excluded. Overall, 23 studies were included in this study. Studies were published from 2000 to 2021, subject age range was 15 to 35 years, with documented prevalence of shoulder injuries in female athletes playing overhead sports.

STUDY DESIGN

Systematic review.

LEVEL OF EVIDENCE

Level 2.

DATA EXTRACTION

Two independent researchers completed abstract and full-text review. Data extraction used the Covidence and Cochrane Consumer guide template.

RESULTS

Volleyball was the most common sport with shoulder injuries (6/23; 26%) followed by softball 5/23 (22%), swimming 5/23 (22%), gymnastics 4/23 (17%), tennis 3/23 (13%), water polo 2/23 (8%), and basketball 1/23 (4%). Six RFs (dominant shoulder, volume/overuse, time in sport, older age at time of injury, past injury, and multidirectional instability) were described. Of the 23 studies, 9 (39%) identified the dominant shoulder as a RF for sustaining injury (mean risk ratio [RR], 2.04), while 6 (26%) cited volume of repetition and overuse as a prominent RF (RR, 1.45).

CONCLUSION

This systematic review demonstrates important RFs for shoulder injuries in female athletes associated with playing overhead sports. Multiple prevention strategies are described. Prevention programs are helpful in reducing the risk of reinjury.

Upper Extremity Musculoskeletal Profiles in Tennis Players: A Systematic Review

CONTEXT

Tennis-specific musculoskeletal (MSK) screening can assess range of motion (ROM) and muscular imbalances. Identifying normative values before implementing a MSK screen is essential in contributing to athlete performance and injury risk profiles.

OBJECTIVE

To review upper extremity MSK data in healthy tennis players across age, sex, and level of play.

DATA SOURCE

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed for this review. A search was conducted in MEDLINE, SPORTDiscus, Embase, and CINAHL.

STUDY SELECTION

This review included shoulder, elbow, and wrist ROM, isometric strength, or isokinetic strength in a tennis population. Each article was critically appraised to help identify the internal and external validity of each study.

STUDY DESIGN

Systematic review.

LEVEL OF EVIDENCE

Level 3.

DATA EXTRACTION

A total of 41 studies met the search criteria. Each contributor organized the data elements of interest into data tables, with a second contributor assigned for review. Data elements of interest included player and study characteristics: ROM, isometric dynamometry, and isokinetic strength.

RESULTS

A total of 3174 players were included in the final studies. Most of the players included were competitive adolescents and young adults; 15 studies included ROM data. Male tennis players consistently had more external rotation (ER) gain (range, 1.8º to 8.8º) and internal rotation (IR) loss (range, -15.3º to -3.0º) when compared with their female counterparts (ER range, -2.5º to 5.8º; IR range, -10.4º to -3º). Shoulder IR and ER strength were measured in the majority of all the strength studies, with the external rotators generating at least two-thirds the strength of the internal rotators.

CONCLUSION

Overall MSK data of tennis players indicate that shoulder strength values are often larger than nontennis players, but equal to or slightly lower than comparable athletes in other overhead sports. Adaptive changes of the glenohumeral joint and subsequent rotational motion are similar to those of other overhead athletes.

Effect of isokinetic eccentric training on the human shoulder strength, flexibility, and muscle architecture in physically active men: A preliminary study

Strengthening the rotator cuff muscles is important for injury prevention and rehabilitation. Since muscle fascicle length improves motor performance and is suggested to reduce the risk of injury for the hamstring, it may be an important variable to promote multidirectional changes in the function and macroscopic structure for the shoulder. Recent literature reviews overwhelmingly suggest that eccentric exercises improve fascicle length and functional measures for the lower limb. However, there is a research gap for the shoulder. Since ultrasound imaging is the most commonly used imaging technique to quantify muscle structure, but has yielded heterogeneous results in different studies, there is another issue and a research gap for the imaging method. Based on the research gaps, the purpose of this study was to evaluate the effects of standardized eccentric strength training on the function and structure of the external rotator cuff muscles using an isokinetic dynamometer and MRI. Therefore, a preliminary pre-post intervention study was conducted and 16 physically active men were recruited in October 2021. For the right shoulder, an eccentric isokinetic training was performed twice a week for almost six weeks. The primary outcome measures (external rotators) were active and passive range of motion, eccentric and concentric torque at 30, 60, and 180°/s isokinetic speed, and fascicle length and fascicle volume for the supraspinatus and infraspinatus muscles. The findings show a training effect for the absolute mean values of eccentric strength (+24%, p = .008). The torque-angle relationship increased, especially in the final phase of range of motion, although a 4% (p = .002) decrease in passive range of motion was found in the stretch test. Positive changes in muscle structure were shown for the supraspinatus muscle fascicle length (+16%, p = .003) and fascicle volume (+19%, p = .002). Based on the study results, we can conclude that eccentric isokinetic training has a significant positive effect on the shoulder. To our knowledge, this is the first eccentric training study using both isokinetic dynamometer and muscle diffusion tensor imaging to access functional and structural changes in the human shoulder rotator cuff muscles. The methods were shown to be applicable for interventional studies. Based on these results, populations such as high-performance handball players with highly trained shoulders should be included in future studies.

The impact of resistance-based training programs on throwing performance and throwing-related injuries in baseball players: A systematic review

The aim of this systematic review is to assess the effects of structured resistance training programs on the throwing performance and injury risk of baseball players, irrespective of their age or sex. The literature search was carried out on 18/10/2023, utilizing databases that include PubMed, Scopus, and the Web of Science. Our inclusion criteria encompassed research involving baseball players of all ages and sex who had undergone resistance-based training interventions. For comparison, we considered active control groups, irrespective of their exposure to additional training programs. The outcomes under investigation were related to throwing performance (i.e., throwing velocity and accuracy) and injuries associated with throwing. In our review, we exclusively included studies with a two- or multi-arm design. We evaluated the risk of bias using the PEDro scale. Out of the initial pool of 509 studies, we carefully examined 27 full-text articles and ultimately selected and analyzed 16 studies for inclusion in our review. Out of the 12 studies that compared and presented the inferential statistics for the post-training effects of the experimental versus control groups, it was observed that 8 of these studies demonstrated a significantly more favorable impact of the experimental group on enhancing throwing velocity when compared to the control group. Out of the three studies that compared the experimental and control groups in terms of throwing accuracy, only one study showed a significant improvement in the experimental group compared to the control group after the intervention. In conclusion, this systematic review indicates that resistance-based training interventions appear to be effective in enhancing throwing velocity. However, the evidence regarding the efficacy of these interventions in improving throwing accuracy is less robust. It is worth noting that while some experimental conditions may lead to an increase in injury rates, there is limited data available on this aspect, with only a few studies reporting on this variable.

Effect of Indian clubbell exercises on cricket fast bowlers' shoulder kinematics

Background

The glenohumeral joint's rotational range of motion (ROM) and muscle strength are essential to execute the cricket bowling action. Performing shoulder rotation exercises may increase the rotator cuff muscle strength and rotational ROM.

Objectives

The aim of this study was to test the effect of a six-week exercise programme on shoulder rotational ROM and muscle strength.

Methods

Twenty-one healthy male cricket fast bowlers were recruited, ranked and pair-matched on initial shoulder rotator muscle strength and assigned to either a shoulder exercise (SE) group or cricket training (CT) only group. The SE group incorporated Indian clubbell exercises in addition to their cricket training.

Results

Bowlers in both groups displayed a large increase on the dominant shoulder's internal rotation (IR) ROM, but only the SE group's bowlers displayed ROM improvements (p<0.001) bilaterally for both internal and external rotation. The CT group's fast bowler's non-dominant shoulder IR ROM significantly decreased (p=0.02) during the six weeks. Between groups, only the SE group's bowler's internal rotator muscle strength improved (p<0.001) bilaterally. The observed kinematic changes were statistically significantly greater at a 5% level for the SE group's bowlers (bilateral internal rotators muscle strength, non-dominant shoulder IR ROM and horizontal adduction ROM).

Conclusion

Maintenance of the shoulder's rotational ROM and muscle strength is vital for a fast bowler. Cricket bowlers who perform regular clubbell exercises might increase their shoulder's ROM and internal rotator cuffs' muscle strength, which may aid in stabilising their glenohumeral joint while bowling.

Tele-Assessment of Functional Capacity: Validity, Intra- and Inter-rater Reliability

BACKGROUND

Functional capacity evaluation is a standardized tool that assesses work-related skills. Although there are different test batteries, the most frequently used one is Work Well Systems. This study aims to determine the validity and inter- and intra-rater reliability of remote implementation of functional capacity tests (repetitive reaching, lifting object overhead, and working overhead) in asymptomatic individuals.

METHODS

A total of 51 asymptomatic individuals were included in the study. Participants completed all tests both face-to-face and remotely. Remote assessment videos were rewatched by the same researcher and different researchers for intra- and inter-rater reliability. All processes were scored by two independent researchers.

RESULTS

Remotely performing repetitive reaching (intraclass correlation coefficient [ICC]: 0.85-0.92, p < .001), lifting object overhead (ICC: 0.98, p < .001), and working overhead (ICC: 0.88 p < .001) tests are valid and reliable.

DISCUSSION

Repetitive reaching, lifting an object overhead, and sustained overhead work tests in the Work Well Systems-Functional Capacity Evaluation test battery can be performed remotely through videoconferencing. Remotely evaluating these tests, which are especially important in work-related situations, may be important in pandemic conditions and hybrid working conitions.

Acromiohumeral distance quantification during a variety of shoulder external and internal rotational exercises in recreationally overhead athletes

To determine whether shoulder external (ER) and internal rotational (IR) exercises at five different shoulder abduction angles affect the acromiohumeral distance (AHD). Twenty recreational overhead athletes were included. AHD was measured using real-time ultrasound for each of the five shoulder conditions as follows: neutral shoulder rotation (active-hold) and during ER and IR exercises (isometric and concentric) at five different shoulder-abduction angles (0°, 30°, 45°, 60°, and 90° of abduction). A two-way ANOVA was used to analyze AHD values. Shoulder abduction angle × exercise interaction for AHD was found (F16,304 = 10.92; p < .001; η2 = 0.37). For both isometric and concentric conditions, AHD increased during IR exercises (p < .05) yet decreased during ER exercises (p < .05) when compared with each active-hold positions. Shoulder ER and IR exercises influence the AHD in recreational overhead athletes. A larger AHD was observed during shoulder IR exercises, whereas ER exercises failed to maintain the AHD.

Effects of an 8-week multimodal program on thoracic posture, glenohumeral range of motion and serve performance in competitive young tennis players

Introduction

Intensive tennis practice is known to generate sport-specific adaptations at the shoulder region and influence the sagittal spinal curvature. However, increased thoracic kyphosis decreases the shoulder functional capacity, which could limit tennis performance. Therefore, the aim of this study was to investigate the effects of an 8-week multimodal program on thoracic posture, glenohumeral range of motion, and serve performance in competitive young tennis players.

Methods

Eighteen male and four female players (age: 16.0 ± 2.4 years, height: 170.7 ± 11.0 cm; mass: 62.1 ± 11.5 kg; International Tennis Number: 3-4) performed their regular training during 8 weeks, which was used as a reference period, and implemented a multimodal program including stretching, strengthening, and myofascial release exercises, four times per week during 8 additional weeks, which corresponded to the intervention period. The thoracic curvature angle and mobility, the biacromial and interscapular distances, the glenohumeral range of motion and the tennis serve performance were assessed three times, i.e., before and after the regular training and after the 8-week multimodal program.

Results

The results showed that the 8-week regular training had no significant effects on thoracic curvature angle [effect size (ES) = 0.02-0.36, p = 0.06-0.46] and mobility (ES = 0.05-0.26, p = 0.13-0.42), biacromial (ES = 0.05, p = 0.18) and interscapular distances (ES = 0.03, p = 0.45), ranges of motion in glenohumeral internal (ES = 0.04, p = 0.43) and external rotation (ES = 0.43, p = 0.06), and tennis serve accuracy (ES = 0.33, p = 0.07) and velocity (ES = 0.09, p = 0.35). The 8-week multimodal program increased moderately the thoracic mobility (ES = 0.55, p = 0.01), moderately to strongly the serve accuracy and velocity (ES = 0.65, p = 0.003, for both), strongly decreased the interscapular distance (ES = 1.02, p < 0.001), and strongly increased the range of motion in glenohumeral internal (ES = 0.90, p < 0.001) and external rotation (ES = 1.49, p < 0.001).

Discussion

These findings indicated that an 8-week multimodal program, including spine and glenohumeral mobility and shoulder girdle strength exercises, performed four times per week during 8 weeks, is moderately relevant to rectify the sagittal thoracic curvature in competitive tennis players, while such a program may help regain the range of motion in glenohumeral rotation without tennis serve performance impairment.

The Effects of a Compensatory Training Program Adding an Isoinertial Device in the Shoulder Function on Young Tennis Players

ABSTRACT

Fernandez-Fernandez, J, Moreno-Perez, V, Cools, A, Nakamura, FY, Teixeira, AS, Ellenbecker, T, Johansson, F, and Sanz-Rivas, D. The effects of a compensatory training program adding an isoinertial device in the shoulder function on young tennis players. J Strength Cond Res 37(5): 1096-1103, 2023-The aim of this study was to analyze whether a compensatory training program, including isoinertial flywheel training, could reduce shoulder imbalances in a group of asymptomatic young tennis players. After an initial evaluation, 26 young tennis players were assigned to either a supervised flywheel training group (FTG, n = 13) or a control group (CG, n = 13). Shoulder passive internal (IR) and external rotation (ER) range of motion (ROM) as well as shoulder IR and ER maximal isometric strength were measured before and after a 12-week training intervention, performed 3 times per week. After the intervention, results showed significant changes for IR ( p < 0.001, effect size [ES] = 1.83) and ER ( p < 0.001, ES = 1.77) on the dominant (D) side, and IR on the nondominant (ND) side ( p < 0.001, ES = 2.24) in the FTG compared with the CG. Regarding the ROM values, results showed that the FTG achieved significantly greater increases for the IR ROM ( p < 0.001, ES = 3.32) and total ROM (TROM) ( p = 0.004, ES = 1.39) on the D and ND sides (IR ROM: p = 0.002, ES = 1.53; TROM: p < 0.001, ES = 2.35) than the CG. Moreover, the CG displayed larger decrements in ER ROM ( p = 0.016, ES = 1.12) on the ND side after the training period than the FTG. The conducted compensatory training program was effective to increase the ER strength and IR mobility of the FTG players, which led to a reduction in the glenohumeral imbalances.

Shoulder Rotational Strength and Range of Motion in Unilateral and Bilateral Overhead Elite Athletes

CONTEXT

Overhead athletes place tremendous demands on the shoulder complex, which result in adaptive kinematics but potential susceptibility to injury. This study aimed to compare shoulder glenohumeral range of motion (ROM) and rotator muscles strength in bilateral and unilateral overhead sports.

DESIGN

Cross-sectional study; secondary care.

METHODS

Forty-two elite athletes (17.7 [4.5] y; 42.9% female), including 18 swimmers and 24 badminton players, were included. Preseason glenohumeral rotation ROM and isokinetic shoulder internal and external rotator muscles strength was tested (60°·s-1). Bilateral (nondominant:dominant) and agonist:antagonist (external rotator:internal rotator) conventional and functional deceleration ratios (eccentric to concentric) were calculated. The impact of sport and number of competitive years on shoulder ROM and strength was tested.

RESULTS

Badminton players had greater glenohumeral internal rotation deficit, total ROM deficit, and lower bilateral strength ratio than swimmers (P < .050). Rotational strength was positively associated with the competitive years, but greater in swimmers (P < .050) and on the internal rotator (P < .001). The functional deceleration ratio was negatively associated with the competitive years on the dominant side in swimmers and for both sides in badminton.

CONCLUSIONS

Unilateral overhead athletes had greater ROM and rotational strength asymmetries than bilateral athletes. Interestingly, the functional deceleration ratio was lower over time on the dominant shoulder for both sports, but, surprisingly, also on the nondominant shoulder in badminton, potentially creating a greater risk for shoulder injuries.

Shoulder rotation strength and overhead shooting speed associated with prior shoulder injury in water polo players

This study aimed to differentiate peak ball speed during shooting and shoulder rotation strength of the dominant arm between previously injured (PI) and uninjured (UI) water polo players. Nine PI and nine UI players performed 10 shots at 6 m from the goal mouth and three sets of three repetitions of isokinetic shoulder strength tests at 180 degrees/s on a dynamometer. Peak ball speed and shoulder concentric internal rotation (CIR) and eccentric external rotation (EER) peak torque (PT) and total work (TW) normalised to body mass were measured. EER:CIR PT and TW ratios were calculated. All PI versus UI comparisons were made using an Independent Samples T-Test. PI players shot 6% faster, produced 18% more CIR PT, and had lower EER:CIR PT (22%) and TW (34%) ratios compared with UI players. Shoulder TW compared with PT ratios could be more sensitive in differentiating PI versus UI players as TW takes into account the muscles' capacity throughout full active ROM. Practitioners could expand their foci to monitor shoulder EER:CIR TW ratios, in addition to PT ratios, to identify muscle imbalances in water polo athletes who might be at risk of injury/reinjury, and thereafter design interventions to reduce these imbalances.

Etiologic Factors of Rotator Cuff Disease in Elderly: Modifiable Factors in Addition to Known Demographic Factors

With the aging society, musculoskeletal degenerative diseases are becoming a burden on society, and rotator cuff disease is one of these degenerative diseases. The purpose of this study was to examine the incidence of shoulder osteoarthritis and the etiologic factors of rotator cuff disease in the Korean elderly population. A total of 102 patients performing ultrasonography were recruited, and their demographic factors were analyzed. As functional factors, visual analog scale and the peak torque of external and internal rotators of the shoulder using an isokinetic dynamometer were measured. As an anatomical factor, the acromiohumeral distance in the plain radiograph of the glenohumeral anterior-posterior view was used. There were more female patients (65.7%) than male patients (34.3%). The age range with the highest number of respondents was 50–59 years old. The mean visual analogue score was 4.09 (Min 1 to Max 9). Age and dominant hand side factors appear to be the crucial etiologic factors of the presence and severity of rotator cuff disease. The lower net value of the external rotator strength is weakly related to the presence of rotator cuff disease after adjusting for age, and this is the only modifiable factor in the study.

Effectiveness of shoulder injury prevention programs in an overhead athletic population: A systematic review

OBJECTIVE

To analyze the effectiveness of shoulder injury prevention programs in overhead athletes.

DESIGN

Systematic Review.

METHODS

CINAHL, Embase, PubMed, and SPORTDiscus electronic databases were searched from database inception through December 2020 for randomized controlled or prospective cohort studies that implemented shoulder injury prevention programs in overhead athletes and reported shoulder injury incidence rates.

RESULTS

Seven studies fulfilled the inclusion criteria. Two studies reported on odds ratios (OR) that resulted in a reduction of shoulder injuries in overhead athletes following shoulder strengthening and flexibility exercises (OR, 0.72; 95% CI; 0.52, 0.98; OR, 0.22; 95% CI; 0.06, 0.75). One study reported on hazard ratio (HR) that resulted in a reduction of shoulder injuries following stretching of the posterior capsule (HR, 0.36; 95% CI; 0.13, 0.95).

CONCLUSION

There is limited research surrounding the effectiveness of shoulder injury prevention programs in overhead athletes specific to injury reduction. Only three studies reported a favorable effect in terms of injury prevention, with only one study at low risk of bias. At present, no conclusions can be made regarding the effectiveness of shoulder injury prevention programs in the overhead athlete.

Concentric and Eccentric Force Changes with Elastic Band and Isotonic Heavy Resistance Training: A Randomized Controlled Trial

BACKGROUND

Inclusion of resistance training as part of a general fitness program to improve health, and lower risk of disease and injury is well established. Two common options to improve strength are elastic bands and weights. Comparison between elastic bands (as the sole resistance) to isotonic strengthening for concentric and eccentric strength outcomes following the use of low repetitions/heavy resistance has not been reported.

HYPOTHESIS/PURPOSE

The purpose was to examine the effects of a four-week isotonic low repetitions/heavy resistance strengthening program compared to a low repetitions/heavy resistance elastic band strengthening program on shoulder external rotation, hip abduction, and elbow flexion concentric and eccentric isokinetic force production in college aged untrained females.

STUDY DESIGN

Randomized Trial.

METHODS

Twenty healthy females performed pre-and-post isokinetic (60 degrees/second) concentric/eccentric testing of the elbow flexors, shoulder external rotators, and hip abductors. Participants were randomly assigned to a four-week independent low repetitions/heavy resistance strengthening program performed with either elastic bands or isotonic exercises.

RESULTS

A significant (p < 0.05) effect of time was found for eccentric elbow flexor and concentric and eccentric hip abduction force production in the elastic band group with post-test values greater than pre-test values. A significant (p < 0.05) effect of time was found for elbow flexor concentric and eccentric force production in the isotonic group with post-test values greater then pre-test values. No significant (p>0.05) effect of time was found for shoulder external rotator concentric and eccentric forces for both groups, the isotonic group's hip abduction concentric and eccentric force production and elastic band group's elbow flexion concentric force production. No significant effect of intervention (p >0.05) on concentric or eccentric elbow flexors, shoulder external rotators, or hip abductors force production was found, with pre-test and post-test values being similar between groups.

CONCLUSION

Health care practitioners and coaches can consider the prescription of a heavy resistance training program with elastic bands or isotonic exercises for an independent exercise program and expect similar concentric and eccentric muscle force changes.

LEVEL OF EVIDENCE

Level 2b.

Shoulder Isokinetic Strength Balance Ratio in Overhead Athletes: A Cross-Sectional Study

BACKGROUND

Studies have grouped different overhead sports and evaluated together the isokinetic strength of shoulder internal (IR) and external (ER) rotator muscles. However, muscular adaptations could be a consequence of the specific sport, and some strength imbalance between these muscles may exist as a consequence of the muscular demand unique to the sport. Therefore, grouping different overhead sports together may not be adequate.

PURPOSE

To compare strength balance ratios between different overhead sports (volleyball, handball, swimming, judo, baseball, softball, functional movements performed at high-intensity interval training, and tennis) with a control athletic group (no overhead group).

STUDY DESIGN

Cross-sectional study.

METHODS

A total of 237 athletes were submitted to isokinetic shoulder strength tests. The isokinetic concentric and eccentric peak torque values of shoulder internal IR and external ER rotator muscles were measured. Conventional (CR) and functional strength ratios (FR) were calculated.

RESULTS

There were no significant differences between the sports for the CR in the male group. Female softball athletes (90.4±13.6%) had a significantly higher CR than judo (67.3±6.9%), volleyball (74.9±15.9%), and swimming athletes (70.3±8.7%). In the female group, judo athletes had lower FR values (0.76±0.19) than soccer athletes (1.31±0.35), volleyball athletes (1.24±0.27), functional movements performed at high intensity (1.10±0.1), and softball athletes (1.40±0.39). Female handball athletes also had a lower FR (0.99±0.25) than soccer athletes (1.31±0.35) and softball athletes (1.40±0.39). Male handball (0.90±0.23), tennis (0.86±0.30), and judo (0.68±0.22) athletes had lower FR values than soccer athletes (1.20±0.21) and volleyball athletes (1.25±0.28).

CONCLUSIONS

CR for males may be analyzed together, as there were no significant differences between them. However, for females, the CR for softball athletes should be analyzed individually. As there were several differences between the overhead sports according to the FRs, the authors suggest caution in grouping overhead athletes across multiple sports. These results could have important implications for the design of injury prevention and rehabilitation programs associated with the shoulder joint in overhead sports.

LEVEL OF EVIDENCE

3.

The Effect of Shoulder Injury Prevention Program on Shoulder Isokinetic Strength in Young Male Volleyball Players

The purpose of this study was to examine the effects of an eight-week 11 + S programme on isokinetic shoulder strength in young male volleyball players. Twenty-eight top-level young male volleyball players were recruited for this study. The players were randomly assigned into intervention (14 players) and control (14 players) groups. The intervention group performed the 11 + S as a warm-up before training at least three times a week for eight weeks. Dominant shoulder strength was measured using an isokinetic dynamometer at 60°/s and 180°/s. The functional deceleration ratio (FDR) was calculated as a functional strength profile. 20% FDR improvement after eight weeks of 11 + S at 180°/s (p = 0.003) were observed. No other statistically significant effects for shoulder strength improvement was observed (p > 0.05). Eight weeks of 11 + S warm-up programme improved the glenohumeral muscle imbalance by increasing the functional deceleration ratio (FDR) of shoulder muscles in young male volleyball players.

FOREARM POSITION MATTERS DURING ECCENTRIC SHOULDER EXERCISES: AN EMG RECRUITMENT STUDY WITH IMPLICATIONS FOR REHABILITATION

Background

Eccentric exercise has demonstrated great utility in the rehabilitation of various shoulder pathologies. Research on the electromyographic (EMG) activity of the shoulder musculature during these activities is limited, however. Furthermore, no studies have observed how forearm positioning during exercise affects EMG output.

Purpose/Hypothesis

The purpose was to examine the degree of specific muscle recruitment among commonly used eccentric exercises in rehabilitation of the upper extremity and shoulder. Secondarily, the authors hypothesized that different hand/forearm positions would alter EMG activity within the targeted musculature during a given exercise.

Study Design

Prospective cross-sectional observation of EMG analysis.

Methods

This study analyzed surface EMG data obtained from 10 healthy individuals during five eccentric exercises of the dominant extremity, performed in a randomized order: side-lying eccentric horizontal abduction (SL ER), half-kneeling weighted ball decelerations (BALL DC), seated eccentric external rotation in scaption (STD ER), standing eccentric external rotation at 0deg (STND ER), supine eccentric external rotation at 90deg (SUP ER). Each exercise was performed with two to three forearm position variants commonly used in clinical environments: neutral, pronation, and/or supination. EMG data were collected from the upper trapezius, infraspinatus, teres minor, latissimus dorsi, and anterior/middle/posterior deltoid. Data were analyzed for each individual exercise and within each muscle using a mixed-model ANOVA repeated across forearm position. Significant interactions were followed by a Bonferroni post-hoc test for pairwise comparisons. Effect size was calculated for all significant pairwise comparisons using a Cohen's d statistic.

Results

Significant differences in EMG activity for the selected musculature exist between forearm positions for four of the five exercises and Cohen's d effect sizes 0.178 - 1.159.

Conclusion

Specific eccentric shoulder exercises activate muscles of the shoulder complex differently based on forearm positioning.

Level of Evidence

Level 2.

Neuro-mechanical aspects of playing-related mobility disorders in orchestra violinists and upper strings players: a review

Orchestra musicians are at high risk of neuro-mechanical disorders due to the intense stresses their body withstand, leading to pain and injury. This review presents a comprehensive account of the works on the circumstances and types of playing related mobility disorders of upper strings players, as well as on the relevant neuro-mechanical factors and perspectives to those disorders. The following aspects are considered: asymmetry and imbalance in the musculo-skeletal system, muscle-bone-joint interactions, repetitive overloading and fatigue. An additional factor relates to neuro-muscular redundancy in the motor system, whereby more muscles and tendons than strictly necessary are engaged in performing a motor task, thus making the system indeterminate, with no unique solution. This same task can be performed with different muscle combinations. It is thus of interest to verify whether playing disorders may be alleviated by considering alternative techniques of performance.

Influence of Shoulder Position on Functional Control Ratio During Isokinetic Assessment

CONTEXT

One of the possible mechanisms leading to secondary impingement syndrome may be the strength imbalance of shoulder rotators which is known as functional control ratio (FCR). The FCR is a ratio dividing the eccentric peak torque of the external rotators by the concentric peak torque of the internal rotators. Previous studies have focused on the reproducibility and reliability of isokinetic assessment, but there is little information on the influence of variable shoulder positions on FCR.

OBJECTIVE

To compare shoulder FCR across 3 different shoulder abduction positions during isokinetic assessment.

DESIGN

Cross-sectional study.

SETTING

Biomechanics laboratory.

PARTICIPANTS

Thirty-one healthy young university students (age 22.35 [0.95] y, weight 60.52 [9.31] kg, height 168.23 [9.47] cm).

INTERVENTIONS

The concentric peak torque of internal rotators and eccentric peak torque of external rotators of right shoulder were measured on an isokinetic dynamometer.

MAIN OUTCOME MEASURES

Concentric peak torque of the internal rotators and eccentric peak torque of the external rotators, measured using an isokinetic dynamometer.

RESULTS

The concentric peak torque of internal rotators was significantly lower at 120° shoulder abduction compared with other positions (P < .001). The FCR was significantly higher at 120° shoulder abduction than 90° (P = .002) or 60° (P < .001) shoulder abduction because of the lower concentric peak torque. No significant difference was found in the FCR between the other 2 shoulder positions (P = .14).

CONCLUSIONS

Shoulder position variations may influence FCR because of weakness of the internal rotators. Rehabilitation and injury prevention training programs should specifically focus on strengthening the internal rotators at more elevated angles of shoulder abduction.

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.

Applied Sport Science for Male Age-Grade Rugby Union in England

Rugby union (RU) is a skill-collision team sport played at junior and senior levels worldwide. Within England, age-grade rugby governs the participation and talent development of youth players. The RU player development pathway has recently been questioned, regarding player performance and well-being, which sport science research can address. The purpose of this review was to summarise and critically appraise the literature in relation to the applied sport science of male age-grade RU players in England focussing upon (1) match-play characteristics, (2) training exposures, (3) physical qualities, (4) fatigue and recovery, (5) nutrition, (6) psychological challenges and development, and (7) injury. Current research evidence suggests that age, playing level and position influence the match-play characteristics of age-grade RU. Training exposures of players are described as 'organised chaos' due to the multiple environments and stakeholders involved in coordinating training schedules. Fatigue is apparent up to 72 h post match-play. Well-developed physical qualities are important for player development and injury risk reduction. The nutritional requirements are high due to the energetic costs of collisions. Concerns around the psychological characteristics have also been identified (e.g. perfectionism). Injury risk is an important consideration with prevention strategies available. This review highlights the important multi-disciplinary aspects of sport science for developing age-grade RU players for continued participation and player development. The review describes where some current practices may not be optimal, provides a framework to assist practitioners to effectively prepare age-grade players for the holistic demands of youth RU and considers areas for future research.

The Effectiveness of a Dry-Land Shoulder Rotators Strength Training Program in Injury Prevention in Competitive Swimmers

Competitive swimmers usually undergo large mileage of daily training, in which propulsive force is produced mainly by the upper limbs. Some studies claim that dry-land shoulder rotators injury prevention programs before the in-water swim practice are paramount. However, the effect of shoulder strengthening prior to water training is unclear. This study aimed to analyse the acute effects of training programs conducted on dry land with the goal of preventing shoulder rotators injuries. A group of young swimmers (N = 23) was recruited to participate in this research. The peak torques of shoulder internal and external rotators were assessed before and after the completion of the compensatory strength training program. The isokinetic assessment was performed using two different protocols: 3 repetitions at 60^⍛/s and 20 repetitions at 180^⍛/s. Except for a trivial reduction in strength after the training program, there were no other significant differences in any of the studied variables (shoulders rotators endurance, strength and muscle balance). All results showed trivial to small effect sizes. Our findings suggest that a compensatory strength training program does not have a significant acute effect on the strength, endurance and muscle balance of shoulder rotators in young swimmers.

Joint pain and osteoarthritis in former recreational and elite cricketers

BACKGROUND

Sport participants are at increased risk of joint pain and osteoarthritis. A better understanding of factors associated with joint pain and osteoarthritis in this population could inform the development of strategies to optimise their long-term joint health. The purpose of the study was to describe the prevalence of joint pain and osteoarthritis in former cricketers, and determine whether playing position, playing standard (i.e. elite or recreational standard) and length-of-play are associated with region-specific joint pain.

METHODS

The data were from the Cricket Health and Wellbeing Study (CHWS), a cohort of 2294 current and former cricketers (played ≥1 season) in England and Wales. For this study, eligible individuals had to be aged ≥30 years and be a former cricket participant. Joint pain was defined as region-specific (hip/knee/ankle/shoulder/hand/back) pain on most days of the last month. Osteoarthritis was defined as joint-specific doctor-diagnosed osteoarthritis. Logistic regression was used to calculate unadjusted and adjusted (for history of joint injury resulting in > 4 weeks of reduced activity +/- age) odds ratios (ORs) and 95% confidence intervals (95% CIs).

RESULTS

846 individuals from the CHWS were former cricketers aged ≥30 years (3% female, aged median 62(IQR 54-69) years, 62% played cricket recreationally, median 33(IQR 21-41) cricket seasons). One-in-two (48%) reported joint pain and 38% had been diagnosed with osteoarthritis. Joint pain and OA were most common in the knee (23% pain, 22% osteoarthritis), followed by the back (14% pain, 10% osteoarthritis) and hand (12% pain, 6% osteoarthritis). After adjusting for injury, bowlers had greater odds of shoulder pain (OR (95% CI) 3.1(1.3, 7.4)) and back pain (3.6(1.8, 7.4)), and all-rounders had greater odds of knee (1.7(1.0, 2.7)) and back pain (2.1(1.0, 4.2)), compared to batters. Former elite cricketers had greater odds of hand pain (1.6(1.0, 2.5)) than former recreational cricketers. Playing standard was not related to pain at other sites, and length-of-play was not associated with joint pain in former cricketers.

CONCLUSIONS

Every second former cricketer experienced joint pain on most days of the last month, and more than one in three had been diagnosed with osteoarthritis. Compared with batters, bowlers had higher odds of shoulder and back pain and all-rounders had higher odds of back and knee pain. Elite cricket participation was only related to higher odds of hand pain compared with recreational cricket participation.

General versus sports-specific injury prevention programs in athletes: A systematic review on the effects on performance

INTRODUCTION

Injury prevention programs (IPPs) are an inherent part of training in recreational and professional sports. Providing performance-enhancing benefits in addition to injury prevention may help adjust coaches and athletes' attitudes towards implementation of injury prevention into daily routine. Conventional thinking by players and coaches alike seems to suggest that IPPs need to be specific to one's sport to allow for performance enhancement. The systematic literature review aims to firstly determine the IPPs nature of exercises and whether they are specific to the sport or based on general conditioning. Secondly, can they demonstrate whether general, sports-specific or even mixed IPPs improve key performance indicators with the aim to better facilitate long-term implementation of these programs?

METHODS

PubMed and Web of Science were electronically searched throughout March 2018. The inclusion criteria were randomized control trials, publication dates between Jan 2006 and Feb 2018, athletes (11-45 years), injury prevention programs and included predefined performance measures that could be categorized into balance, power, strength, speed/agility and endurance. The methodological quality of included articles was assessed with the Cochrane Collaboration assessment tools.

RESULTS

Of 6619 initial findings, 22 studies met the inclusion criteria. In addition, reference lists unearthed a further 6 studies, making a total of 28. Nine studies used sports specific IPPs, eleven general and eight mixed prevention strategies. Overall, general programs ranged from 29-57% in their effectiveness across performance outcomes. Mixed IPPs improved in 80% balance outcomes but only 20-44% in others. Sports-specific programs led to larger scale improvements in balance (66%), power (83%), strength (75%), and speed/agility (62%).

CONCLUSION

Sports-specific IPPs have the strongest influence on most performance indices based on the significant improvement versus control groups. Other factors such as intensity, technical execution and compliance should be accounted for in future investigations in addition to exercise modality.

Effects of 8-Week Functional vs. Traditional Training on Athletic Performance and Functional Movement on Prepubertal Tennis Players

Yildiz, S, Pinar, S, and Gelen, E. Effects of 8-week functional vs. traditional training on athletic performance and functional movement on prepubertal tennis players. J Strength Cond Res 33(3): 651-661, 2019-In recent years, studies on functional training (FT) have gained importance among older adults and health care services, but there is a lack of research on the athletic performance of children. Fundamental movement skills are basic skills that need to be improved by the age of 10, and these skills are fundamental to every sport. While developing these basic movement skills, some athletic abilities of children should not be neglected and will be a basis for the future. In this way, children will have the ability to perform their sport-specific movement skills easily when the age of specialization comes. Our hypothesis is that increased functional movement will enhance athletic performance of child tennis players. Question of the study is "will increased functional movement enhance athletic performance of child tennis players?" The purpose of this study is to investigate the effects of the FT model on the athletic performance of young athletes. This study included 28 young tennis players (mean age: 9.6 ± 0.7, height: 134.1 ± 6.8, body mass: 31.3 ± 4.1, and fitness age: 3.1 ± 1.1) who have an 80% or more dominant side based on the lateralization test and a functional movement screen (FMS) score below 75%. Ten subjects were included in each of the FT group (FTG) and the traditional training group (TTG), 8 subjects were included in the control group (CG). The training program was implemented on 3 nonconsecutive days in a week for 8 weeks. All subjects performed CG exercises; FTG performed additional exercises based on the FT model, and TTG performed additional exercises based on the TT model. Flexibility, vertical jump, acceleration, agility, balance, and FMS tests were conducted before the training program, at the end of the fourth and the eighth week. The Friedman test analysis method bearing intragroup repeated measurements was used to evaluate the effects of the training program on the dependent variables among weeks (beginning the fourth week and the eighth week) since groups display distribution in nonparametric order. The differences between the averages were tested with Wilcoxon post hoc analyses. The Kruskal-Wallis Test analyses method was used to evaluate the effects of the training program on dependent variables among the groups (CG, TTG, and FTG). The differences between the averages were tested with Mann-Whitney U post hoc analyses. Intraclass correlation coefficient (ICC) values were calculated to determine the test-retest reliability of all measurements. According to the data, there was no difference in performance measurements between CG, TTG, and FTG before the exercise program (p > 0.05), but the differences between the groups were significant (p < 0.01) after 4 weeks and 8 weeks. A significant decrease was found in FMS score in CG (p < 0.01), while no difference was found in other parameters (p > 0.05). In TTG, FMS score significantly decreased (p < 0.01), dynamic right balance (p < 0.01) and dynamic left balance (p < 0.05) increased. But, no statistically significant difference was found in other parameters (p > 0.05) in TTG. In FTG, all parameters improved, and differences were statistically significant (p ≤ 0.001). Based on these results, the FT model seems to be more effective than the TT model in terms of increasing athletic performance.

Injury Prevention Strategies for Adolescent Cricket Pace Bowlers

Adolescent cricket pace bowlers are prone to non-contact shoulder, low back and lower-limb injuries. Exercise-based injury prevention programmes (IPPs) are effective for reducing non-contact injuries in athletes; however, a specific programme for adolescent pace bowlers has not been published. This paper therefore seeks to provide a rationale for the development of an exercise-based IPP specific for adolescent pace bowlers. It also outlines design principles and provides an example exercise programme that can be implemented at the community level. In addition, the paper addresses other injury prevention techniques concerned with the prescription of appropriate bowling loads and the modification of poor bowling biomechanics. Performing an exercise-based IPP before cricket training could reduce injury rates in adolescent pace bowlers. Eccentric strengthening exercises can be employed to target injuries to the posterior shoulder muscles, hip adductors and hamstring muscles. The risk of low back, knee and ankle injury could also be reduced with the inclusion of dynamic neuromuscular control exercises and trunk extensor endurance exercises. Other prevention strategies that need to be considered include the modification of poor bowling biomechanics, such as shoulder counter-rotation and lateral trunk flexion. Coaches and players should also aim to quantify bowling load accurately and coaches should use this information to prescribe appropriate individualised bowling loads. Specifically, players would benefit from avoiding both long periods of low load and acute periods when load is excessively high. Future evidence is needed to determine the effectiveness of the example programme outlined in this paper. It would also be beneficial to investigate whether the modification of bowling biomechanics is achievable at the non-elite level and if bowling load can be accurately measured and manipulated within a community-level population.

Isokinetic assessment of shoulder complex strength in adolescent elite synchronized swimmers

Children and adolescent participation in sport has increased in recent years. Synchronized swimming requires correct muscle balance in the shoulder complex. The purpose of this study was to establish isokinetic strength profiles and peak torque ratios of shoulder internal and external rotator muscles in a female high-level synchronized swimming team. Twenty-six adolescent female high-level synchronized swimmers, aged 12-14, participated in this study. Maximal bilateral shoulder concentric external and internal rotation force was measured at 60°/s (5 repetitions) and 180°/s (15 repetitions). The isokinetic concentric strength generated by the internal rotator muscles was significantly higher (p < 0.05) than by the external rotators in both limbs and at both velocities. Significant bilateral differences in the external rotation (ER):internal rotation (IR) strength ratio were noted at 60°/s. Isokinetic assessment is essential in sports medicine, since it is the only test capable of diagnosing any shoulder strength deficit.

National Athletic Trainers' Association Position Statement: Evaluation, Management, and Outcomes of and Return-to- Play Criteria for Overhead Athletes With Superior Labral Anterior-Posterior Injuries

OBJECTIVE

  To present recommendations for the diagnosis, management, outcomes, and return to play of athletes with superior labral anterior-posterior (SLAP) injuries.

BACKGROUND

  In overhead athletes, SLAP tears are common as either acute or chronic injuries. The clinical guidelines presented here were developed based on a systematic review of the current evidence and the consensus of the writing panel. Clinicians can use these guidelines to inform decision making regarding the diagnosis, acute and long-term conservative and surgical treatment, and expected outcomes of and return-to-play guidelines for athletes with SLAP injuries.

RECOMMENDATIONS

  Physical examination tests may aid diagnosis; 6 tests are recommended for confirming and 1 test is recommended for ruling out a SLAP lesion. Combinations of tests may be helpful to diagnose SLAP lesions. Clinical trials directly comparing outcomes between surgical and nonoperative management are absent; however, in cohort trials, the reports of function and return-to-sport outcomes are similar for each management approach. Nonoperative management that includes rehabilitation, nonsteroidal anti-inflammatory drugs, and corticosteroid injections is recommended as the first line of treatment. Rehabilitation should address deficits in shoulder internal rotation, total arc of motion, and horizontal-adduction motion, as well as periscapular and glenohumeral muscle strength, endurance, and neuromuscular control. Most researchers have examined the outcomes of surgical management and found high levels of satisfaction and return of shoulder function, but the ability to return to sport varied widely, with 20% to 94% of patients returning to their sport after surgical or nonoperative management. On average, 55% of athletes returned to full participation in prior sports, but overhead athletes had a lower average return of 45%. Additional work is needed to define the criteria for diagnosing and guiding clinical decision making to optimize outcomes and return to play.

Neuromuscular adaptations in shoulder function and dysfunction

Neuromuscular activity, organized in coordinated patterns, forms the basis of task-specific function in sports and exercise. The content and extent of these patterns may be variable, but include elements of activation/inhibition, co-activation, concentric/eccentric activation, proximal-to-distal activation, plyometric activation, and preactivation stiffness. They may be based on inherent neuromuscular architecture, but are commonly affected by positive or negative adaptations to imposed functional demands. Positive neuromuscular adaptations improve the efficiency of performing the task, which can result in less energy expenditure, maximum force delivered to the task, and protection of involved joints from excessive loads/motions, and improve the effectiveness of task performance. They frequently result from specific training in task mechanics and optimal conditioning of the neuromuscular structures involved in the task. Negative neuromuscular maladaptations can affect the efficiency of performing the task, increase energy expenditure and loads, decrease the effectiveness of task performance, and can be associated with clinical presentation of injury symptoms. They can result from overload, injury, and/or limited recovery. This chapter will focus specifically on shoulder joint function to provide examples of positive adaptations and negative maladaptations. It will then provide guidelines for clinical evaluation, treatment of clinical injury, and training/conditioning, based on understanding the neuromuscular activation.

The effects of preventive rubber band training on shoulder joint imbalance and throwing performance in handball players: A randomized and prospective study

OBJECTIVES

To investigate the effects of a strength training program (STP) using rubber band exercises.

METHODS

Twenty-five athletes were divided into two groups: muscular imbalance in the dominant (D) and in the non-dominant (ND) upper limbs. Each group was subdivided into experimental and control groups. Experimental groups performed eighteen sessions of STP. Athletes were submitted to ball throwing and isokinetic strength tests to assess the muscular strength of the shoulder rotator muscles and conventional and functional balance ratios.

RESULTS

STP improved external rotator peak torque (18.0 ± 0.8 to 21.3 ± 1.0 Nm, p < 0.01) and total work (29.3 ± 0.9 to 34.5 ± 1.5 J, p < 0.01) in the D experimental group, while only total work (34.8 ± 2.5 to 37.6 ± 3.1 J, p < 0.03) improved in the D control group. The ND experimental group also presented significant improvement in external rotator peak torque (18.8 ± 0.8 to 21.1 ± 1.3 Nm, p < 0.01) and total work values (29.0 ± 1.4 to 34.6 to 1.6 J, p < 0.01) while there was no strength improvement in the ND control group. The ND experimental group showed an improvement in conventional (61.5 ± 3.5 to 72.7 ± 3.0%, p = 0.03) and functional (1.0 ± 0.1 to 1.6 ± 0.08, p < 0.01) ratios. STP did not improve the conventional ratio in the D experimental group. However, STP produced a large effect size. The D experimental group presented an improvement in ball velocity (49.0 ± 2.4 to 52.5 ± 2.2 km/h, p = 0.04) in standing position throwing.

CONCLUSIONS

STP improves muscular strength of external rotator muscles and muscular balance.

Upper Extremity Strength Imbalance after Mastectomy and the Effect of Resistance Training

The purpose of this non-randomized pre/post comparison trial was to explore the effect of resistance training (RT) on upper extremity strength imbalance in breast cancer survivors. Seventeen right-side dominant female breast cancer survivors (age: 58.2±2.7 years; BMI: 27.8±1.1 kg/m ² ) with right-sided (RSM) or left-sided (LSM) mastectomy completed strength testing (30-second arm curl) before and after an 8-week RT program. At baseline, LSM (n=8) had equal strength bilaterally (right=16.8±1.1 repetitions; left=16.4±1.4 repetitions), whereas RSM (n=9) had impaired strength on the right (16.7±1.3 repetitions) compared to the left (18.6±1.1 repetitions) side ( p <0.01). After RT, RSM increased strength by 25% on the right (initially weaker) side and 19% on the left (initially stronger) side, which resolved the imbalance. By comparison LSM increased 19% on both sides that were initially equal in strength. Based on our findings, breast cancer survivors with dominant-side mastectomy are at risk for upper extremity strength imbalance that can be resolved with a relatively short-term RT program.

Survey of Hand and Upper Extremity Injuries Among Rock Climbers

BACKGROUND

Rock climbing first evolved as a sport in the late 18th century. With its growing popularity, the number of rock climbing-related injuries has potential to increase, spurring a rise in the number of articles associated with it. Despite the available literature, there remains a paucity of information about upper extremity injuries sustained by rock climbers, and no studies to date have focused on gender-specific injuries.

METHODS

A 24-question online survey was distributed to rock climbers about upper extremity injuries sustained during rock climbing. Statistical analysis was used to study association between participants' demographics and injuries.

RESULTS

A total of 397 participants responded to the survey. Mean age was 32.5 years with males comprising 85%. No significant differences in demographics or climbing behaviors were found between males and females. Ninety percent of participants reported sustaining an upper extremity injury. Fingers were the most common injury followed by shoulder/arm and elbow/forearm. Our study found females to be more likely to report a rock climbing-related injury, and more likely to undergo surgery for it.

CONCLUSION

Female rock climbers were significantly more likely to report a shoulder/upper arm injury and were also more likely to report undergoing surgery compared with males, where these differences were not due to age or climbing behaviors. Further investigation is warranted into the association between shoulder injuries and female athletes to determine how the gender differences relate to extent of injury as well as health service utilization behaviors.

Reducing musculoskeletal injury and concussion risk in schoolboy rugby players with a pre-activity movement control exercise programme: a cluster randomised controlled trial

Background

Injury risk in youth rugby has received much attention, highlighting the importance of establishing evidence-based injury reduction strategies.

Aim

To determine the efficacy of a movement control exercise programme in reducing injuries in youth rugby players and to investigate the effect of programme dose on injury measures.

Methods

In a cluster-randomised controlled trial, 40 independent schools (118 teams, 3188 players aged 14–18 years) were allocated to receive either the intervention or a reference programme, both of which were to be delivered by school coaches. The intervention comprised balance training, whole-body resistance training, plyometric training, and controlled rehearsal of landing and cutting manoeuvres. Time-loss (>24 hours) injuries arising from school rugby matches were recorded by coaches and medical staff.

Results

441 time-loss match injuries (intervention, 233; control, 208) were reported across 15 938 match exposure-hours (intervention, 9083; control, 6855). Intention-to-treat results indicated unclear effects of trial arm on overall match injury incidence (rate ratio (RR)=0.85, 90% confidence limits 0.61 to 1.17), although clear reductions were evident in the intervention arm for concussion incidence (RR=0.71, 0.48 to 1.05). When trial arm comparisons were limited to teams who had completed three or more weekly programme sessions on average, clear reductions in overall match injury incidence (RR=0.28, 0.14 to 0.51) and concussion incidence (RR=0.41, 0.17 to 0.99) were noted in the intervention group.

Conclusion

A preventive movement control exercise programme can reduce match injury outcomes, including concussion, in schoolboy rugby players when compared with a standardised control exercise programme, although to realise the greatest effects players should complete the programme at least three times per week.

Sling-based Exercise for External Rotator Muscles: Effects on Shoulder Profile in Young Recreational Tennis Players

Context: Tennis playing generates specific adaptations, particularly at the dominant shoulder. It remains to be established whether shoulder strength balance can be restored by sling-based training for adolescent recreational tennis players. Objective: We added a sling-based exercise for shoulder external rotators to investigate its effects on external rotator muscle strength, on internal rotator muscle strength, on glenohumeral range of motion and on tennis serve performance. Design: Test-retest design. Setting: Tennis training sports facilities. Participants: Twelve adolescent male players volunteered to participate in this study (age: 13.3 ± 0.5 years; height: 1.64 ± 0.07 cm, mass: 51.7 ± 5.8 kg, International Tennis Number: 8). Intervention: The procedure spanned 10 weeks. For the first five weeks, players performed their regular training (RT) twice a week. For the last five weeks, a sling-based exercise (SE) for strengthening the shoulder external rotator muscles was added to their regular training. Main Outcome Measures: Maximal isometric strength of shoulder external and internal rotator muscles and glenohumeral range of motion in external and internal rotation were assessed in both shoulders. Serve performance was also evaluated by accuracy and post-impact ball velocity, using a radar gun. Results: No change was found in any measurement after the RT period. Significant increases in external (~+5%; p<0.001) and internal (~+2%; p<0.05) rotator muscle strength and in external/internal strength ratio (~+4%; p<0.001) were observed after the SE period. Serve velocity and accuracy were significantly improved after SE (~+2% and ~+24%, respectively; p<0.05 for both), while no clinically meaningful alterations in ranges of motion were observed. Conclusions: Prophylactic intervention through sling-based exercise for strengthening shoulder external rotator muscles appears effective in restoring strength balance at the dominant shoulder, and may prevent adolescent tennis players from sustaining degenerative shoulder problems which could later impair their performance of daily and work-related tasks.

Humeral elevation reduces the dynamic control ratio of the shoulder muscles during internal rotation

OBJECTIVES

To determine the differences in the dynamic control ratio of the glenohumeral joint rotators, during internal rotation at 20° and 60° of humeral elevation in the scapular plan. Dynamic control ratio (DCR) is defined as the ratio between eccentric action of the lateral rotators and the concentric action of the medial rotators.

DESIGN

A cross-sectional laboratory study.

METHODS

Thirty asymptomatic participants (men n=14, women n=16, mean age=29.4±8.9years, BMI: 24.1±5.4) were tested. Peak torque generated by the concentric action of the MR and the eccentric action of the LR of the shoulder joint and the DCR were evaluated on the dominant arm using an isokinetic dynamometer at 20° and 60° of humeral elevation at a speed of 20°/s.

RESULTS

There was a significant decrease in the DCR at 60° humeral elevation when compared to 20° humeral elevation (p<0.05). This decrease was due to the significant decrease in eccentric peak torques at 60° humeral elevation when compared to 20° (p<0.05). However, there was no significant difference in the concentric peak torques between 20° and 60° (p>0.05).

CONCLUSIONS

The significant decrease in the DCR as a consequence of a decrease in the eccentric peak torque of the LR when the humerus is in a more elevated position suggests that the introduction of humeral elevation can be used as a progression for improving the eccentric action of the shoulder LR and subsequently the dynamic control of the shoulder.

Shoulder injuries in soccer goalkeepers: review and development of a FIFA 11+ shoulder injury prevention program

In the last years, shoulder injuries have represented an increasing health problem in soccer players. The goalkeepers are more exposed to shoulder disorders than other field players. Injury prevention exercises for upper limbs were cited in few studies involving throwing athletes, but we know that goalkeepers need a specific program. The purpose of this study is to describe the development of an adapted Fédération Internationale de Football Association (FIFA) 11+ program, namely the FIFA 11+ shoulder, which targets the prevention of shoulder injuries in soccer goalkeepers. The FIFA 11+ shoulder program is structured into three parts: general warming-up exercises, exercises to improve strength and balance of the shoulder, elbow, wrist, and finger muscles, and advanced exercises for core stability and muscle control. The exercises were selected based on recommendations from studies demonstrating high electromyographic activity.

Effect of fatigue caused by a simulated handball game on ball throwing velocity, shoulder muscle strength and balance ratio: a prospective study

BACKGROUND

Arm throwing represents a deciding element in handball. Ball velocity, aim accuracy, and dynamic stability of the shoulder are factors that influence throwing effectiveness. The purpose of this study was to examine the influence of muscle fatigue caused by simulated game activities (SGA) on shoulder rotational isokinetic muscle strength, muscle balance and throwing performance, and to examine the relationship between muscle strength and throwing performance.

METHODS

Ten national elite adult handball athletes were evaluated. Isokinetic internal (IR), external (ER) rotators peak torque, and balance ratio were measured before and after SGA. Ball throwing velocity was assessed by radar gun.

RESULTS

Both internal (IR) and external (ER) rotators peak torque were significantly lower after SGA (p = 0.0003 and p = 0.02, respectively). However, the deleterious effect was more evident for IR than ER muscles (effect size r = 0.39 and r = 0.18, respectively). Balance ratio before and after SGA did not differ (p = 0.06). Ball throwing velocity was not impaired by SGA. Moreover, isokinetic variables correlated positively with ball velocity (r ≥ 0.67).

CONCLUSIONS

SGA affected the muscle strength of IR more than ER, predisposing the shoulder joint to muscular imbalance. The muscular impairment after SGA was insufficient to impair ball throwing velocity.

Shoulder proprioception - lessons we learned from idiopathic frozen shoulder

Background

Of all the most frequent soft tissue disorders of the shoulder, idiopathic frozen shoulder (IFS) offers the greatest potential for studying proprioception. Studies concerning the presence of proprioception dysfunctions have failed to determine the potential for spontaneous healing of passive shoulder stabilizers (anterior and posterior capsule, middle and inferior gleno-humeral ligaments), its relationship with passive (PJPS) and active (AJPS) shoulder proprioception for internal and external rotation (IR, ER), as well as the isokinetic muscle performance of the internal and external rotators. This study investigates these dependencies in the case of arthroscopic release of IFS.

Methods

The study group comprised 23 patients (average aged 54.2) who underwent arthroscopic release due to IFS and 20 healthy volunteers. The average follow-up time was 29.2 months. The Biodex system was used for proprioception measurement in a modified neutral arm position and isokinetic evaluation. The results were analysed using the T-test, Wilcoxon and interclass correlation coefficient. P-values lower than 0.05 were considered significant.

Results

Statistically significant differences were found between involved (I) and uninvolved (U) shoulders only in the cases of PJPS and AJPS, peak torque, time to peak torque and acceleration time for ER (p < 0.05). No statistically significant difference was noted between PJPS IR and PJPS ER or between AJPS IR and AJPS ER (p > 0.05) for the U shoulders.

Conclusions

The anatomical structure of anterior (capsule, middle and anterior band of inferior gleno-humeral ligament) and posterior (capsule and posterior band of inferior gleno-humeral ligament) passive shoulder restraints has no impact on the difference in PJPS values between ER and IR in a modified neutral shoulder position. The potential for spontaneous healing of the anterior and posterior passive shoulder restraints influences PJPS recovery after arthroscopic release of IFS. ER peak torque deficits negatively affect AJPS values. PJPS and AJPS of ER and IR can be measured with a high level of reproducibility using an isokinetic dynamometer with the arm in a modified neutral shoulder position. Differences greater than 15 % for PJPS and >24 % for AJPS for ER and IR can be helpful for future studies as baseline data for identification of particular passive and active shoulder stabilizers at risk.

Functional Movement Screening Performance of Brazilian Jiu-Jitsu Athletes From Brazil: Differences Considering Practice Time and Combat Style

Boscolo Del Vecchio, F, Foster, D, and Arruda, A. Functional movement screening performance of Brazilian jiu-jitsu athletes from Brazil: differences considering practice time and combat style. J Strength Cond Res 30(8): 2341-2347, 2016-Brazilian jiu-jitsu (BJJ) is a grappling combat sport that athletes, lying (guard fighter) or kneeling (pass fighter) on the mat, attempt to force their opponents to submit. Brazilian jiu-jitsu practices may result in muscular imbalances, which increase the risk of injury. Instead, the Functional Movement Screen (FMS) is an evaluation routine that could be related to injury incidence and seeks to detect muscular imbalance and movement dysfunction. Thus, the aim of the study was to investigate the injury profile and the FMS score and their relationship, with consideration for the BJJ fight style. Sports injuries were recorded in the last 12 months of 33 BJJ athletes, and the statistical analyses were applied to a routine evaluation FMS and a score of 14 points or less was considered low performance in FMS. We used a logistic regression; the effect size (ES) was calculated, and 5% was assumed as the statistical significance level. Pass fighters showed a higher percentage of injuries on the thorax (24.24%) than did guard fighters (6.67%, p = 0.01). Upper limbs were the most injured part of the body (χ = 36.7; p < 0.001), and they were 79% of the injuries that occurred in training sessions (χ = 14.53; p < 0.001). Despite the lack of statistical differences in the FMS performance between guard and pass fighters (t = 1.97; p = 0.05), its magnitude was considered medium (ES = 0.77). There was an association between FMS and presence of injury (χ = 4.95; p = 0.03). Considering the FMS score as a predictor and the presence or absence of injury as the dependent variable, the data met a Wald coefficient of 4.55, p = 0.03 and Exp (B) = 5.71. The study found that almost half of the sample had injuries in the upper limbs and a quarter had injuries in the lower limbs in the last year. A poor FMS score was observed, and lower scores in the FMS were associated with a higher risk of injury in BJJ athletes.

The efficacy of a movement control exercise programme to reduce injuries in youth rugby: a cluster randomised controlled trial

Background

Injuries to youth rugby players have become an increasingly prominent health concern, highlighting the importance of developing and implementing appropriate preventive strategies. A growing body of evidence from other youth sports has demonstrated the efficacy of targeted exercise regimens to reduce injury risk. However, studies have yet to investigate the effect of such interventions in youth contact sport populations like rugby union.

Objective

To determine the efficacy of an evidence-based movement control exercise programme compared with a sham exercise programme to reduce injury risk in youth rugby players. Exercise programme compliance between trial arms and the effect of coach attitudes on compliance will also be evaluated.

Setting

School rugby coaches in England will be the target of the researcher intervention, with the effects of the injury prevention programmes being measured in male youth players aged 14–18 years in school rugby programmes over the 2015–2016 school winter term.

Methods

A cluster-randomised controlled trial with schools randomly allocated to either a movement control exercise programme or a sham exercise programme, both of which are coach-delivered. Injury measures will derive from field-based injury surveillance, with match and training exposure and compliance recorded. A questionnaire will be used to evaluate coach attitudes, knowledge, beliefs and behaviours both prior to and on the conclusion of the study period.

Outcome measures

Summary injury measures (incidence, severity and burden) will be compared between trial arms, as will the influence of coach attitudes on compliance and injury burden. Additionally, changes in these outcomes through using the exercise programmes will be evaluated.

Trial registration number

ISRTCNN13422001.

Periodization and physical therapy: Bridging the gap between training and rehabilitation

BACKGROUND

Exercise prescription and training progression for competitive athletes has evolved considerably in recent decades, as strength and conditioning coaches increasingly use periodization models to inform the development and implementation of training programs for their athletes. Similarly, exercise prescription and progression is a fundamental skill for sport physical therapists, and is necessary for balancing the physiological stresses of injury with an athlete's capacity for recovery.

OBJECTIVE

This article will provide the sport physical therapist with an overview of periodization models and their application to rehabilitation.

SUMMARY

In recent decades models for exercise prescription and progression also have evolved in theory and scope, contributing to improved rehabilitation for countless athletes, when compared to care offered to athletes of previous generations. Nonetheless, despite such advances, such models typically fail to fully bridge the gap between such rehabilitation schemes and the corresponding training models that coaches use to help athletes peak for competition. Greater knowledge of periodization models can help sport physical therapists in their evaluation, clinical reasoning skills, exercise progression, and goal setting for the sustained return of athletes to high level competition.

Effects of Six Weeks of Medicine Ball Training on Throwing Velocity, Throwing Precision, and Isokinetic Strength of Shoulder Rotators in Female Handball Players

The aim of this study was to investigate the effects of 6 weeks of medicine ball training (MBT) on throwing velocity, throwing precision, and isokinetic strength of shoulder rotators in competitive female handball players. Twenty-eight players (mean ± SD; age: 20.8 ± 3.3 years, height: 170.5 ± 5.6 cm, body mass: 65.2 ± 8.0 kg) were randomly assigned to an MBT group (TG; n = 15) and a control group (CG; n = 13). TG performed a supervised MBT program, 3 times a week for a total of 6 weeks, focusing on handball-specific movement patterns. Both groups, TG and CG, also conducted a supervised shoulder injury prevention program with elastic tubes, as part of the warm-up, finishing with regular handball throws. Results showed a significant group × time interaction in throwing velocity (p < 0.001) with the TG posttest results being significantly higher compared with CG (d = 2.1), and also a significant main time effect (p < 0.001), with an increase in throwing velocity of 14% (d = 3.0) and 3.7% (d = 0.3) for both TG and CG, respectively. Throwing precision did not significantly differ between groups and time points. Isokinetic strength measures revealed a significant group × time interaction (p ≤ 0.05) with the TG posttest results being significantly higher compared with CG (d = 0.9) and also a significant main time effect (p < 0.01) with an increase of 15% (d = 0.9) in concentric shoulder internal rotation at 180°·s⁻¹ in the dominant arm in TG, whereas no significant changes occurred in CG. The present results indicate that 6 weeks of MBT elicit significant improvements in functional performance (i.e., throwing velocity) in female handball players, whereas throwing precision remained unaffected. Medicine ball training exercises seem to be a useful and inexpensive strength training strategy in enhancing functional performance by closely mimicking sport-specific movement activities.

Measuring Eccentric Strength of the Shoulder External Rotators Using a Handheld Dynamometer: Reliability and Validity

CONTEXT

Shoulder strength assessment plays an important role in the clinical examination of the shoulder region. Eccentric strength measurements are of special importance in guiding the clinician in injury prevention or return-to-play decisions after injury.

OBJECTIVE

To examine the absolute and relative reliability and validity of a standardized eccentric strength-measurement protocol for the glenohumeral external rotators.

DESIGN

Descriptive laboratory study.

SETTING

Testing environment at the Department of Rehabilitation Sciences and Physiotherapy of Ghent University, Belgium.

PATIENTS OR OTHER PARTICIPANTS

Twenty-five healthy participants (9 men and 16 women) without any history of shoulder pain were tested by 2 independent assessors using a handheld dynamometer (HHD) and underwent an isokinetic testing procedure.

INTERVENTION(S)

The clinical protocol used an HHD, a DynaPort accelerometer to measure acceleration and angular velocity of testing 30°/s over 90° of range of motion, and a Biodex dynamometer to measure isokinetic activity.

MAIN OUTCOME MEASURE(S)

Three eccentric strength measurements: (1) tester 1 with the HHD, (2) tester 2 with the HHD, and (3) Biodex isokinetic strength measurement.

RESULTS

The intratester reliability was excellent (0.879 and 0.858), whereas the intertester reliability was good, with an intraclass correlation coefficient between testers of 0.714. Pearson product moment correlation coefficients of 0.78 and 0.70 were noted between the HHD and the isokinetic data, showing good validity of this new procedure.

CONCLUSIONS

Standardized eccentric rotator cuff strength can be tested and measured in the clinical setting with good-to-excellent reliability and validity using an HHD.