Kinetic Chain Research Articles

Single-legged landing behavior of high school basketball players with chronic ankle instability

ObjectivesAnterior cruciate ligament injury is one of the most serious ligamentous injuries. The purpose is to compare the impact of the ankle joint on the knee during landing between athletes with chronic instability and a control group (coper group) and to verify the effects of the kinetic chain from other joints. DesignProspective study. SettingHigh school basketball. ParticipantsParticipants were 62 female high school basketball players who had participated in team sports for >6 months. Main outcome measuresPlayer joint angles, movements, and moments. ResultsThe knee valgus moment was significantly higher in the chronic ankle instability group than in the coper group (20%–60% [p < 0.01]; 80%–100% [p < 0.05]) during landing motion. The knee valgus moment was also significantly higher during the change from the maximum knee joint flexion position to the maximum extension (p < 0.05). In addition, the landing motions of the chronic instability group may have utilized suboptimal compensatory motor strategy on the sagittal plane, depending heavily on the knee joint's abduction moment. ConclusionsOur findings indicate that the chronic ankle instability group uses a different landing strategy pattern than the coper group by changing the joint moment and joint angle during landing, which may increase the risk of anterior cruciate ligament injury.

Developing a Rehabilitation Guideline (REGUIDE) for Patients Undergoing an Arthroscopic Bankart Repair After Traumatic Anterior Shoulder Dislocation, Focusing on Managing Apprehension: An International Delphi-Based Consensus Study.

OBJECTIVE: We aimed to develop a consensus-based rehabilitation guideline specifically designed to reduce apprehension following arthroscopic Bankart repair after traumatic anterior shoulder dislocation. DESIGN: Delphi-based consensus. METHOD: A comprehensive list of interventions for potential inclusion in a postoperative rehabilitation guideline was developed. American and European physiotherapists and orthopedic surgeons were invited to participate in a Delphi panel, engaging in 3 survey rounds. The health professionals were surveyed about their level of agreement on both initially listed and newly suggested interventions. Consensus was established when a "critical-to-include" rating was given in ≥70% of all responses. Ten former patients were consulted to identify the intervention during standard care rehabilitation that had the most impact on reducing postoperative apprehension following ABR. Any interventions not initially listed in the first round were added to the second survey round of the Delphi process. RESULTS: Forty-four health professionals reached consensus on a set of 27 interventions for managing apprehension after arthroscopic Bankart repair. New interventions included gradual exposure to shoulder positions eliciting apprehension, training in anterior stability-provoking positions, and education addressing the impact of psychosocial factors. Former patients identified specific interventions that were effective in reducing postoperative apprehension following ABR. These interventions encompassed medicine ball throws, active-assisted wall slides, and kinetic chain exercises in anterior stability-provoking positions. CONCLUSION: Our Delphi process informed expert recommendations for various interventions aimed at addressing apprehension associated with ABR. The recommendations were the foundation for developing a rehabilitation guideline (REGUIDE). The REGUIDE integrates principles from cognitive-behavioral therapy to improve rehabilitation and mitigate apprehension. J Orthop Sports Phys Ther 2024;54(5):1-13. Epub 20 March 2024. doi:10.2519/jospt.2024.12106.

The associations of physical parameters with the Closed Kinetic Chain Upper Extremity Stability Test, the Upper Quarter Y Balance Test, and the Upper Limb Rotation Test in professional overhead athletes

ObjectiveTo investigate the associations of glenohumeral internal (IR) and external rotation (ER), horizontal adduction (HA), and thoracic spine rotation ranges of motion (ROM), isometric muscle strength of the shoulder rotators, and trunk muscle endurance with the Closed Kinetic Chain Upper Extremity Stability Test (CKCUEST), the Upper Quarter Y Balance Test (YBT-UQ), and the Upper Limb Rotation Test (ULRT) in overhead athletes. DesignCross-sectional study. SettingsLaboratory. ParticipantsOne hundred twenty-one athletes were enrolled. Main outcome measuresIndependent variables were: IR, ER, HA, and thoracic spine rotation ROMs, isometric muscle strength of glenohumeral IR and ER muscles, and trunk muscle endurance. Dependent variables were: CKCUEST, YBT-UQ, ULRT. ResultsIR ROM of the nondominant side was associated with the CKCUEST, the YBT-UQ, and the ULRT. IR muscle strength of the dominant side was associated with the CKCUEST and the ULRT. Trunk flexor and lateral endurance of the dominant side were associated with the CKCUEST and the YBT-UQ, respectively. ConclusionsMany of the physical parameters influencing scores on the CKCUEST and the YBT-UQ are different. Common parameters influence the CKCUEST and ULRT scores, yet more parameters influence the CKCUEST score. We suggest the combined use of the CKCUEST and the YBT-UQ in overhead athletes.

Relationships among lateral medicine ball throw test performance, HIP and trunk muscle strength, and lower limb kinematics: A cross-sectional study

IntroductionThe lateral medicine ball throw (LMBT) test is used to evaluate the throwing action, involving the entire kinetic chain and the principle of force transfer, with association between the strength of the lower limb and trunk muscles and the lower limb kinematics. The LMBT to investigate the association between lower limb kinematics and hip and trunk muscle strength. ExperimentalThis was a cross-sectional study with 84 healthy and physically active young people. Determinations were made of the maximum isometric strengths of the hip abductor, lateral rotator, extensor, and flexor muscles, and the trunk lateral flexors and extensors. Kinematic analyses (2D) of the hip, knee, and ankle in the sagittal and frontal planes were performed during the countermovement phase of the LMBT, together with quantification of LMBT. Statistical analysis of the associations employed multiple linear regression, with α = 5%. ResultsThere were significant associations between the LMBT and the independent variables hip extensors strength, trunk flexors strength, valgus angle, and knee flexion angle and gender. The regression model presented adjusted R2 = 0.622. ConclusionsLMBT was influenced by the trunk flexor and hip extensor muscle strengths, knee flexion kinematics, lower limb valgus in the countermovement phase, and gender.

Motor alterations along the kinetic chain in amateur volleyball and handball athletes with shoulder pain: An observational comparative study

Overhead sports overload the shoulder complex due to movement repetition and the great amount of force created during the athletic motion, which may cause adaptations in the shoulder and lead to shoulder pain. However, overhead movements include the kinetic chain, and alterations in some of the structures throughout the kinetic chain may increase stress on the shoulder complex and be associated with shoulder pain. PurposeTo compare kinetic chain components in overhead athletes with and without shoulder pain. MethodsForty-one volleyball and handball athletes (21 with and 20 without shoulder pain) were included and assessed for hip internal (IR) and external rotation (ER) range of motion (ROM), hip and trunk isometric strength, trunk endurance and neuromuscular control of the lower and upper limbs (Y balance test). ResultsAthletes with shoulder pain showed smaller IR ROM in both hips, lower endurance time for trunk extensors and flexors, decreased reach distance in the anterior and posteromedial direction, as well as a smaller composite score in the Y balance test (p < 0.05). ConclusionVolleyball and handball athletes with shoulder pain showed changes in ROM throughout the kinetic chain in addition to lower core endurance, and decreased neuromuscular control of lower limbs.

Effects of Telerehabilitation Combining Diaphragmatic Breathing Re-Education and Shoulder Stabilization Exercises on Neck Pain, Posture, and Function in Young Adult Men with Upper Crossed Syndrome: A Randomized Controlled Trial.

Background: Forward head posture and rounded shoulder posture are common postural variants found in upper crossed syndrome, which can lead to limited neck mobility, respiratory problems, and other issues. The purpose of this study was to investigate the effects of telerehabilitation, combining diaphragmatic breathing re-education and shoulder stabilization exercises, on young men with upper crossed syndrome during the COVID-19 pandemic over 4 weeks. Methods: The study included 37 participants aged in their 20s and 30s who were randomly divided into two groups. The experimental group received diaphragmatic breathing re-education and shoulder stabilization exercises, while the control group only underwent shoulder stabilization exercises. Both groups were trained three times a week for four weeks using telerehabilitation. The comparison of within-group pre-post differences in the experimental and control groups was conducted using a paired t-test, while the effects of treatment were assessed using repeated-measures analysis of variance. Results: After 4 weeks, both groups showed significant improvements in the pain pressure threshold of the upper trapezius, craniovertebral angle, round shoulder posture, shoulder tilt degree, neck disability index, and closed kinetic chain upper extremity stability test (all p < 0.05). The results showed a significant difference between the Time effect (p adj < 0.05/4) for both sides of PPT, CVA, and STD and both sides of RSP, NDI, and CKCUEST, and an interaction between the Time × Group effects (p adj < 0.05/4) for the Rt. PPT, CVA, and STD. Conclusions: These findings suggest that the telerehabilitation training group, which included diaphragmatic breathing re-education and shoulder stabilization exercises, was more effective in improving Rt. PPT, CVA, and STD in males with UCS.

PERBEDAAN PENGARUH OPEN KINETIC CHAIN EXERCISE DAN CLOSE KINETIC CHAIN EXERCISE TERHADAP KEKUATAN OTOT QUADRICEPS FEMORIS PASCA OPERASI ANTERIOR CRUCIATE LIGAMEN DITINJAU DARI USIA

This research is an experimental research. The sample is post-Anterior Cruciate Ligament surgery patients at the Solo Sport Physiotherapy Clinic as many as 16 people including Open and Close exercise categories and based on adolescent and adult age categories. Samples were taken using purposive sampling technique. The variables in this study include: 1) Quadriceps Femoris Muscle Strength (Y); 2) Open Exercise (a1); 3) Close Exercise (a2); and 4) Age (b). Research data were obtained from measurements using an Electromyograph. Hypothesis testing using two-way Anova test and t test. Conclusion, (1) There is a difference in the effect of quadriceps femoris muscle strength after being given open kinetic chain and close kinetic chain exercises in ACL postoperative patients. Which means that close kinetic chain training has a better improvement than open kinetic chain in ACL postoperative patients. (2) There are differences in the effect of quadriceps femoris muscle strength in adolescent and adult athletes. Which means that adult athletes have a better increase in quadriceps femoris muscle strength compared to adolescent athletes. (3) There is no interaction between open kinetic chain and close kinetic chain training methods with adolescent and adult age on increasing quadriceps muscle strength.

Association between core strength and dynamic balance of throwing hand in professional healthy cricket fast bowlers: A cross sectional study

BackgroundThe core musculature gets activated by feed forward fashion during the movement of upper extremity, as in kinetic chain of throwing, shoulder muscle contributes larger dynamic balance and also in reversed manner. Aim of the current study was to associate the strength of core and the dynamic balance of throwing hand in cricket fast bowlers. Methods72 subjects were initially screened for eligibility, and ultimately, 55 male participants from various cricket coaching academies, aged 19.1 ± 2.6 on average, were included. The mean BMI of the participants was 20.9. The assessments included the Modified Upper Quarter Y Balance Test (mUQYBT)- Medial (M), Supero-Lateral reach (SL), Infero-Lateral reach(IL) along with Core measures- 600 Abdominal flexion test (600 AFT), right side plank test (RSP), Left side plank test (LSP), Beiring Sorenson test (BST), all of which were successfully completed. ResultsBased on our findings, we observed a mild positive correlation between the values of mUQYBT and core measures. We employed Pearson's coefficient to evaluate the association, and the R2 values were utilized to quantify the amount of variability. The resulting scores were RSP to SL (r = 0.38, R2 = 0.14), LSP to SL (r = 0.43, R2 = 0.19), LSP to RSP (r = 0.790, R2 = 0.62), BSP to Composite score (r = 0.29, R2 = 0.08), SL to 600 AFT* (r = 0.231, R2 = 0.05) and BMI to IL* (r = −0.107, R2 = 0.01). ConclusionIn conclusion, a positive correlation was exhibited between dynamic balance and core strength in healthy cricket fast bowlers. Educating bowlers on proper movement techniques and prescribing targeted exercises can enhance dynamic balance, reducing the risk of injuries.

An investigation into the frequency and risk factors of low back pain following surgical treatment of isolated calcaneal fractures.

This study aimed to determine the frequency of low back pain after calcaneal fractures treated with open reduction internal fixation (ORIF) and the risk factors that cause this condition. Thirty-one patients (27 males and 4 females) who underwent surgery for a unilateral calcaneal fracture between 2016 and 2020 and had no complaints of low back pain before fracture surgery were included in the study. The patients were divided into 2 groups: those who developed low back pain after the operation and those who did not. Patients were evaluated with the Life Quality Short Form SF-36, the Oswestry Disability Index (ODI), and American Orthopedic Foot-Ankle Association Score (AOFAS). Sanders' fracture type, joint range of motion (ROM) measurements of injured and uninjured limbs, maximal isometric muscle strength measurements, balance on 1 leg with pedobarographic measurements, and walking time were evaluated. The obtained data were compared among the 2 groups. Low back pain was observed in 71% of the patients and was detected after an average of 6 months from the operation. In ODI, 59.1% of the patients reported that low back pain limited their lives slightly. Patients with low back pain have lower AOFAS scores and worse SF-36 physical functionality than those without low back pain (P < .001, P=.016). Balance time on 1 foot in pedobarographic measurements, foot in ROM, ankle in ankle active, passive plantar flexion, inversion, active hip, passive internal, external rotation, muscle is the foot eversion force. In these measurements, the values of the injured side are intact. It was statistically significantly lower than the other side (interaction P < .1). Low back pain may occur after unilateral calcaneal fractures treated by ORIF. This may be caused by decreased angles of ankle dorsi and plantar flexion, foot inversion, hip abduction, and internal and external rotation. In the rehabilitation program, not only the ankle region but also the hip joint of the affected side should be included, and the kinetic chain that describes the interaction mechanism of the human body should not be forgotten. Level IV, Prognostic Study.

DIFFERENCE BETWEEN MUSCLE ACTIVITIES DURING JUMPING MOTION IN DESCENT AND ASCENT PHASES ON A TRAMPOLINE

Trampoline bounces are performed on a bed of a jumping surface that is stretched over the trampoline apparatus. The jumping motion is divided into a descent phase, i.e., from the landing to the maximum depth, and an ascent phase, from the maximum depth to the takeoff. Most studies on muscle activity during jumping have investigated muscle activity during the same phase between groups or between landing and release; however, no studies have investigated muscle activity between phases. Therefore, this study aimed to investigate muscle activity during the descent and ascent phases and obtain basic data on the jumping motion. For the trials, participants were instructed to perform 15 consecutive jumps on the trampoline bed from a standing still position, as high as possible, straight and straight up in the center of the trampoline bed. The muscle activities of the rectus femoris, tibialis anterior, and lateral gastrocnemius revealed significant increases and larger effect sizes in the descent phase than in the ascent phase (p &lt; 0.01). The muscle activities of the sternocleidomastoid, trapezius, and biceps femoris demonstrated significant increases and medium effect sizes in the descent phase in contrast to the ascent phase (p &lt; 0.01). Pushing down the bed by the muscular activity of the lower extremities is most pursued in the descent phase. Then, participants maintain a straight vertical posture for the body to receive the rebound force from the maximum depth of the bed. This suggests that the sternocleidomastoid and trapezius muscles were significantly active in controlling the head position. A high jump is achieved by pushing the bed down for a deep descent and maintaining a straight posture at the maximum depth. The elastic bed is similar to an Open Kinetic Chain in the descent phase because the load incrementally increases, and to a Closed Kinetic Chain in the ascent phase because the load begins at the maximum depth of the bed. Separating the elements of the jumping motion required in the descent and ascent phases is important in athletic training

Patterns and assessment of spastic hemiplegic gait.

Hemiparetic gait disorders are common in stroke survivors. A circumductory gait is often considered the typical hemiparetic gait. In clinical practice, a wide spectrum of abnormal gait patterns is observed, depending on the severity of weakness and spasticity, and the anatomical distribution of spasticity. Muscle strength is the key determinant of gait disorders in hemiparetic stroke survivors. Spasticity and its associated involuntary activation of synergistic spastic muscles often alter posture of involved joint(s) and subsequently the alignment of hip, knee, and ankle joints, resulting in abnormal gait patterns. Due to combinations of various levels of muscle weakness and spasticity and their interactions with ground reaction force, presentations of gait disorders are variable. From a neuromechanical perspective, a stepwise visual gait analysis approach is proposed to identify primary underlying causes. In this approach, the pelvic and hip joint movement is examined first. The pelvic girdle constitutes three kinematic determinants. Its abnormality determines the body vector and compensatory kinetic chain reactions in the knee and ankle joints. The second step is to assess the ankle and foot complex abnormality. The last step is to examine abnormality of the knee joint. Assessment of muscle strength and spasticity of hip, knee, and ankle/foot joints needs to be performed before these steps. Lidocaine nerve blocks can be a useful diagnostic tool. Recognizing different patterns and identifying the primary causes are critical to developing clinical interventions to improve gait functions.

Relationship between Upper Limb Functional Assessment and Clinical Tests of Shoulder Mobility and Posture in Individuals Participating in Recreational Strength Training.

The upper limb is crucial for functioning in everyday life, thus comprehensive assessment is crucial for physically active people to monitor the effect of exercise and prevent injuries. The aim of this study was to analyse the relationship between upper limb function, shoulder mobility, and posture in individuals who participate in recreational strength training. Thirty-four subjects who engaged in strength training of the upper limbs were divided into two groups: Group 1 (exercise < 3 years) and Group 2 (exercise ≥ 3 years). Lateral scapular slide tests, head and clavicle posture evaluations, and shoulder mobility and closed kinetic chain tests were performed. Group 1 had a greater flexion deficit in both shoulders than Group 2. There was greater external rotation in the non-dominant shoulder and a greater score of the closed kinetic chain test in Group 2 compared to Group 1. There were no statistically significant differences between groups regarding scapula, clavicle, and head posture. The closed kinetic chain test was correlated with a scapula position and symmetry in shoulder flexion in Group 2. Long-term strength training of the upper limbs can be recommended to improve functional abilities in the closed kinetic chain, increase shoulder mobility, and reduce asymmetry.

Evaluation and conservative treatment of shoulder instability in volleyball players an overview

Background: Currently the conservative approach regarding shoulder instability in volleyball player results still be highly contested and discussed in clinical practice. To stipulate a rehabilitation treatment appropriate and personalized, it will be crucial to include the local region in the preliminary assessment compromised and the global kinetic chain, given the numerous correlations between the different body districts. Objective: Evaluate through the collection of literature the best scientific evidence regarding the evaluation and conservative treatment of shoulder instability in volleyball player to be used as an option in situations where surgical treatment would be excessive and invasive for the young athlete. Method: The research was conducted by a single operator through a review of the literature of the last 15 years in databases such as Medline, PubMed and Pedro. The research began in January 2022 and ended in March 2022. The selection of the articles was made on the basis of the reading of the title, abstract and full-text. Result: The research initially yielded 66 scientific articles but after reading the title, abstract and full-text, 19 related articles were considered. The best evidence has been sought regarding treatment protocols for shoulder instability in the athlete. Conclusion: According to the researches carried out the recommendations of the authors and the results obtained by the latter, the conservative approach plays a fundamental role in the recovery in case of shoulder instability. Most athletes have felt positive not only physically but also mentally. Despite this, more extensive studies will be needed in the future, to ensure the professional and the athlete a protocol of conservative recovery as appropriate as possible.

Muscle activity and kinematics during three hamstring strengthening exercises compared to sprinting: A cross-sectional study

Background&#x0D; Sprinting is a crucial task in many sports and remains the major activity during which hamstring muscle injuries occur (Schache et al., 2012). Though the biceps femoris long head predominantly gets injured (Grange et al., 2023), hamstring strengthening exercises frequently seem to activate the semitendinosus more effectively (Bourne et al., 2017). A better understanding of how joint dominance influences activation levels of hamstring muscles may offer more clarity on the appropriate exercise selection in strengthening programs.&#x0D; Purpose&#x0D; This study compared 3 hip-dominant hamstring exercises (the rocker, perpetuum mobile fast and slow; PMfast and PMslow) and the Nordic Hamstring exercise (NHE) on their potential to simulate sprint-like activity and kinematics.&#x0D; Methods&#x0D; Muscle activity of the posterior kinetic chain (mm. biceps femoris, semitendinosus, gluteus maximus and gastrocnemius medialis) was measured with surface electromyography (sEMG) during every exercise and treadmill running at 75% of the individual maximal sprint velocity in 8 male athletes (age: 24.0 years ± SD 2.9; body mass: 76.8 kg ± 7.7; height: 1.79 m ± 0.08). sEMG data was normalized to maximal sprinting. 3D-motion capture was employed to assess hip and knee angles.&#x0D; Results&#x0D; This study revealed higher activity of the hamstrings for the explosive exercises ranging from 63.9% [95%CI: 56.3-71.5%] (rocker) to 49.0% [95%CI: 40.4-57.6%] (PMfast) vs. 34.0% [95%CI: 29.1-38.9%] (NHE) to 32.1% [95%CI: 26.9-37.3%] (PMslow). The rocker especially showed highest hamstring and m. gluteus maximus activity. M. biceps femoris consistently showed higher activity than m. semitendinosus across all exercises in peak (mean difference: 0.16, [95%CI: 0.07-0.26]) and average (mean difference: 0.06, [95%CI: 0.01-0.11]) activity. PMfast, PMslow and NHE demonstrated lower hip flexion angle of peak hamstring activity than the rocker and high-speed running and every exercise showed lower hamstring elongation stress than during high-speed running.&#x0D; Discussion&#x0D; Hamstring activity is comparable to high-intensity treadmill running for NHE and PMslow, and higher for the rocker and PMfast. M. gluteus maximus activity varied, with the rocker and PMfast showing higher activity than in sprinting. All examined exercises demonstrated their peak activity at short hamstring muscle length.&#x0D; What this study adds to the existing knowledge&#x0D; This study generated first data on sprint-specificity of two not yet investigated versions of a unilateral hip thrust. Similar or higher activity than during sprinting and BFlh selectivity was reached through explosive, closed kinetic chain, hip-dominant movement.&#x0D; References&#x0D; Bourne, M. N., Williams, M. D., Opar, D. A., Al Najjar, A., Kerr, G. K., &amp; Shield, A. J. (2017). Impact of exercise selection on hamstring muscle activation. British Journal of Sports Medicine, 51(13), 1021-1028. https://doi.org/10.1136/bjsports-2015-095739&#x0D; Grange, S., Reurink, G., Nguyen, A. Q., Riviera-Navarro, C., Foschia, C., Croisille, P., &amp; Edouard, P. (2023). Location of hamstring injuries based on magnetic resonance imaging: A systematic review. Sports Health, 15(1), 111-123. https://doi.org/10.1177/19417381211071010&#x0D; Schache, A. G., Dorn, T. W., Blanch, P. D., Brown, N. A., &amp; Pandy, M. G. (2012). Mechanics of the human hamstring muscles during sprinting. Medicine &amp; Science in Sports &amp; Exercise, 44(4), 647-658. https://doi.org/10.1249/MSS.0b013e318236a3d2

Intrinsic graft laxity variation with open kinetic chain exercise after anterior cruciate ligament reconstruction: A non-randomized controlled study

ObjectivesTo determine whether quadriceps and hamstring strengthening in a rehabilitation program involving early open kinetic chain (OKC) and/or closed kinetic chain (CKC) knee joint exercises had an influence on graft laxity at 1, 3, and 6 months after anterior cruciate ligament reconstruction (ACLR). DesignRetrospective study. MethodsTwo groups (n = 53) of ACLR patients (combination of OKC and CKC exercises group compared to a CKC exercise group) were recruited. OKC protocol was introduced at 2 weeks post-operatively without external resistance and progressed at 4 weeks with load. Comparative ACL graft laxity measurement and isokinetic strength testing were prospectively performed up to 6 months in both groups. ResultsNo significant differences were observed in the knee laxity at 1 (p = 0.263), 3 (p = 0.263), and 6 months (p = 0.256) follow up between the groups.Similarly, no significant results were observed in within-group knee laxity between 1 and 6 months after ACLR in the intervention (p = 0.155) and control group (p = 0.690). ConclusionThe early initiation of OKC along with CKC exercises doesn't seem to increase the ACLR graft laxity as compared to a rehabilitation program with only CKC exercises.

From Theory to Practice: A Worldwide Cross-Sectional Survey About Flywheel Training in Basketball.

This study aimed to comprehensively investigate the global implementation of flywheel training (FT) by basketball strength and conditioning (S&C)coaches in various contexts, encompassing daily practice, games, and sessions. Survey data were collected from 117 basketball S&C coaches who participated in a 24-question online survey. The survey was structured into 6 key areas, including country and competition, S&C coach context, training methodology, flywheel and competition, postactivation performance enhancement, and recovery. Notably, all respondents emphasized the necessity of a familiarization period with flywheel technology, with a substantial 96% indicating that FT yielded improved player performance on the court. The predominant mention was the conical pulley system. During the season, the prevalent approach involved integrating FT into training twice a week, allocating <15minutes per session, often in conjunction with traditional strength training. A diverse array of lower-body closed kinetic chain exercises were reported, encompassing squats, decelerations, and backward lunges. Intriguingly, FT implementation on match days was unlikely (77%), with the primary aims cited as injury prevention (34%) and enhancing players' strength levels during various phases of the regular season (27%). Recognizing its inherent limitations, this descriptive study provides valuable contextual insights and practical applications for professional basketball practitioners grappling with the utilization of FT.

The Closed Kinetic Chain Upper Extremity Stability Test (CKCUEST) Performance in Elite Team Handball Players Playing with Shoulder Pain, Previous Pain, or No Pain.

Physical therapists use tests that could determine strength and weaknesses of the shoulder for overhead throwing athletes to enhance performance, prevent injury, and safely progress rehabilitation. The Closed Kinetic Chain Upper Extremity Stability Test (CKCUEST) has been proposed to assess muscular capacity and dynamic shoulder stability in overhead athletes, which could provide information to determine a risk of injury. To investigate if the CKCUEST is an appropriate test to implement within team elite handball players to evaluate dynamic shoulder stability across sexes and in the screening of shoulder pain. Cross-sectional study. Elite team handball players were recruited and performed the CKCUEST from which three different scores (raw, touch, and power) were calculated and compared among handball players playing with shoulder pain, previous pain, and no pain. A total of 106 handball players were included: 49 females (1.74±0.03 m, 70.4±6.7 kg, and 22±4.9 years) and 57 males (1.90±0.08 m, 91.6±11.4 kg, and 22±5.4 years), A significant difference was found between the female and male handball players when comparing all three CKCUEST scores (p<0.01). No significant differences were found in the CKCUEST scores among the three different groups (F≤1.23, p≥0.30, η2≤0.03). Among the female participants, no significant differences were found between performing the CKCUEST and the modified test. A significant correlation was found between height and the power score for men (r=0.661, p≤0.001) and women (r=0.434, p=0.01). A comparison of scores across sexes appears unsuitable, due to the possible positive influence of height on the final score. But within the female group, performances of the CKCUEST and the modified CKCUEST were comparable. Additionally, the CKCUEST was not able to differentiate among elite handball players who are playing with shoulder pain, previous shoulder pain, and no pain. 3.

Electromyographic activity of periscapular muscles in symptomatic people: Does scapular dyskinesis have an impact on it?

BACKGROUND: Scapular dyskinesis (SD) is a modification of the positioning and movement of the scapula and is associated with shoulder pain. Exercises to strengthen the shoulder and scapular muscles have been proposed as a therapeutic strategy to reduce pain and improve function. OBJECTIVE: We aimed to investigate the electromyographic activity of the periscapular and trunk muscles in individuals with shoulder pain and SD in different multi-joint exercises. METHODS: Thirty-two subjects with subacromial pain, of both sexes, with the presence or absence of SD, participated in this study. Volunteers performed five repetitions in five exercises (Closed Row; Pronated Row; Push-up; Scapular Push-up; T-push-up). The activity of the upper trapezius, middle trapezius, lower trapezius, serratus anterior, external oblique, and rectus abdominis muscles was recorded using electromyography. RESULTS: Our results showed a decrease in the electromyographic activity of the serratus anterior and external oblique during the T-push-up exercise in individuals with shoulder pain and SD. No differences were observed between groups for the trapezius and the rectus abdominis. CONCLUSIONS: Rehabilitation programs may initially prioritize rowing and push-up exercises to strengthen periscapular muscles. More complex exercises with greater mechanical demand on the kinetic chain, such as the T-push-up, may have to be implemented in later phases.

The Effects of Scapular Stability Training on Serve Speed and Accuracy in College Tennis Players from the Perspective of the Kinetic Chain

Background and Aim: In the tennis serve, the scapula serves as the bony connection between the core, spine, and shoulder. It is the main fulcrum of the body's dynamic chain transmission and plays a very important role in the energy transfer process of the upper limb movement. The objective of this research was to study the effect of scapular stability training in the service kinetic chain on the speed and accuracy of the tennis serve. Materials and Methods: 16 college tennis players from Guangzhou Polytechnic of Sports were randomly selected for this study as a sample group, and divided into an experimental group and a control group, with 8 students for each group (4 males and 4 females). The period of training was 8 weeks. After the tennis training class, only the experimental group will perform scapula stability training twice a week (Monday and Wednesday) for 60 minutes each time. This research used literature methods, expert interviews, experiments, and mathematical statistics to conduct experimental research and theoretical analysis on the effects of scapula stability training on the serving speed and accuracy of college tennis players Results: The results showed that 8 weeks of scapula stability training had a significant effect on improving the stability of athletes' scapula. The scapula stability of the control group (6.81±1.09) and the scapula stability of the experimental group (9.45±1.33). Scapula stability training has a significant effect on the serving accuracy of college tennis players. The serving accuracy of the control group (30.38±5.34) and the serving accuracy of the experimental group (35.50±2.67). Scapula stability training has no significant effect on the serve speed of college tennis players. The serve speed of the control group (136.80±23.89) and the serve speed of the experimental group (122.12±35.71). Conclusion: The results showed that scapular stability and serve accuracy in the experimental group were significantly higher than in the control group (p &lt; 0.05). In terms of serving speed, there was no significant difference between the experimental group and the control group (p&gt;.05). Within the experimental group, there were significant improvements in scapular stability, serve accuracy, and serve speed before and after the experiment (p &lt; 0.05).

Effects of Strengthening Exercises on Human Kinetic Chains Based on a Systematic Review.

Kinetic chains (KCs) are primarily affected by the load of different activities that recruit muscles from different regions. We explored the effects of strengthening exercises on KCs through muscle activation. Four databases were searched from 1990 to 2019. The muscles of each KC, their surface electromyography (sEMG), and the exercises conducted were reported. We found 36 studies that presented muscle activation using the percent (%) maximal voluntary isometric contraction (MVIC) or average sEMG for nine KCs in different regions. The % MVIC is presented as the following four categories: low (≤20%), moderate (21~40%), high (41~60%), and very high (>60%). Only four studies mentioned muscle activation in more than three KCs, while the remaining studies reported inconsistent sEMG processing, lacked normalization, and muscle activation in one or two KCs. The roles of stabilizers and the base of support in overhead throwing mobility using balance exercises were examined, and the concentric phase of chin-up and lat pull-down activated the entire KC by recruiting multiple muscles. Also, deep-water running was shown to prevent the risk of falls and enhance balance and stability. In addition, low-load trunk rotations improved the muscles of the back and external oblique activation. Based on this study's findings, closed-chain exercises activate more groups of muscles in a kinetic chain than open-chain exercises. However, no closed or open chain exercise can activate optimal KCs.