Volleyball Athletes Research Articles

Volleyball Athletes Training Program Towards Their Achievements

Volleyball Athletes Training Program Towards Their Achievements

Development and validation of an overuse injury questionnaire for youth athletes: The Youth Overuse Injury Questionnaire

ObjectiveTo develop and validate the Youth Overuse Injury Questionnaire (YOvIQ). DesignA cross-sectional study. SettingOnline platforms. ParticipantsTwo content experts (in sports injury epidemiology and in sports science and medicine) and seven end-users (youth volleyball athletes) provided feedback during development of the YOvIQ. 227 competitive youth athletes across 14 different sports assessed the psychometric properties of the YOvIQ. Main outcome measuresParticipants completed both YOvIQ and the Oslo Sports Trauma Research Centre Overuse Injury Questionnaire (OSTRC-O2) for anatomical areas of the shoulder, elbow, lower back, knee, and ankle/foot. Validity was assessed via convergent validity. Reliability was assessed using internal consistency estimation and interclass correlation coefficient. ResultsFollowing feedback from content experts, examples and quantitative symbolization were added to the options in YOvIQ, with positive feedback from end-users. Convergent validity between YOvIQ and the OSTRC-O2 was demonstrated with non-significant differences (P ≥ .05) and significant correlations (P < 0.001) for prevalence and severity scores. YOvIQ demonstrated internal consistency for prevalence (Cronbach's alpha coefficient >0.70) and moderate-to-good reliability for severity scores (ICC: 0.51 to 0.88) for shoulder, lower back, and knee. ConclusionsThe YOvIQ is a valid and reliable instrument to identify overuse injuries to the shoulder, lower back, and knee in youth athletes.

Motivational factors for adult amateur volleyball athletes

Motivational factors for adult amateur volleyball athletes

An Analysis Comparing Aggression Levels among Female National Volleyball and Netball Athletes in Sri Lanka

Aggression is an important psychological component that cannot be overlooked when it comes to increasing physical performance, particularly in invasion sports. This research was conducted with the intention of determining the extent of the violent behavior exhibited by the female national netball and volleyball players belonging to Sri Lanka. For the purpose of this study, fifteen female volleyball players and ten female netball players from national teams participated. The data was collected through the use of a standardized and systematic questionnaire, and the findings were analyzed through the application of statistical analysis using SPSS. A two-sample t-test and descriptive statistics were utilized in order to conduct the analysis of the data. The study found that the mean aggressiveness scores for the two national teams were 84.06 and 88.9, respectively. These values were based on aggression. According to the findings of the study, the levels of hostility exhibited by the female players on the country's national teams for netball and volleyball did not differ substantially from one another (p-value = 0.577). According to the findings of the study, the levels of aggressiveness exhibited by both teams were satisfactory, and there was no obvious difference in the levels of aggression exhibited by the female national members of Sri Lanka's netball and volleyball teams. An examination of the psychological situations of athletes and the implementation of strategies to optimize player psychology in order to increase athletic performance are both highlighted by the findings, which show the relevance of these two aspects.

A 2D video-based assessment is associated with 3D biomechanical contributors to dynamic knee valgus in the coronal plane.

Adolescent athletes involved in sports that involve cutting and landing maneuvers have an increased risk of anterior cruciate ligament (ACL) tears, highlighting the importance of identifying risky movement patterns such as dynamic knee valgus (DKV). Qualitative movement screenings have explored two-dimensional (2D) scoring criteria for DKV, however, there remains limited data on the validity of these screening tools. Determining a 2D scoring criterion for DKV that closely aligns with three-dimensional (3D) biomechanical measures will allow for the identification of poor knee position in adolescent athletes on a broad scale. The purpose of this study was to establish a 2D scoring criterion that corresponds to 3D biomechanical measures of DKV. A total of 41 adolescent female club volleyball athletes performed a three-task movement screen consisting of a single-leg squat (SLS), single-leg drop landing (SLDL), and double-leg vertical jump (DLVJ). A single rater scored 2D videos of each task using four criteria for poor knee position. A motion capture system was used to calculate 3D joint angles, including pelvic obliquity, hip adduction, knee abduction, ankle eversion, and foot progression angle. Receiver operating characteristic curves were created for each 2D scoring criterion to determine cut points for the presence of movement faults, and areas under the curve (AUC) were computed to describe the accuracy of each 2D criterion compared to 3D biomechanical data. 3D measures indicated knee abduction angles between 2.4°-4.6° (SD 4.1°-4.3°) at the time point when the center of the knee joint was most medial during the three tasks. AUCs were between 0.62 and 0.93 across scoring items. The MEDIAL scoring item, defined as the knee joint positioned inside the medial border of the shoe, demonstrated the greatest association to components of DKV, with AUCs ranging from 0.67 to 0.93. The MEDIAL scoring criterion demonstrated the best performance in distinguishing components of DKV, specifically pelvic obliquity, hip adduction, ankle eversion, and foot progression. Along with the previously published scoring definitions for trunk-specific risk factors, the authors suggest that the MEDIAL criterion may be the most indicative of DKV, given an association with 3D biomechanical risk factors.

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.

Applicability of the Cumberland Ankle Instability Tool in Elite Volleyball Athletes: A Cross-Sectional Observational Study.

The ease of administration of the Cumberland Ankle Instability Tool (CAIT) could represent a methodology for periodically evaluating athletes, preventing ankle instability injuries. This study aimed to achieve three objectives: (a) to evaluate the applicability of the CAIT scale in volleyball; (b) to explore whether ankle instability presents a greater risk in lower-level volleyball categories and whether elite athletes demonstrate an ability to mitigate this risk; and (c) to identify potential predictors of ankle instability. Eighty female volleyball players participated in this cross-sectional observational study. The CAIT was administered to evaluate the athletes belonging to some teams in Series A, B, and C. The Spearman's ranks correlation coefficient showed significant correlations between CAIT items. Additionally, the Cronbach's α showed a high internal consistency. Our results showed a significant difference between athletes who reported pain and those who did not (p < 0.001). The multiple linear regression model analysis showed that pain was a predictor of ankle instability (p < 0.001). Our findings suggest that the CAIT can be used to evaluate ankle stability in volleyball players. This scale could represent a valuable tool for implementing specific intervention programs to prevent ankle injuries in athletes.

Height, Push-Off Angle, Explosive Power: Do they Correlate with Volleyball Athlete Jumping Performance?

Background and Study Aim: Jump performance is the main asset in attacking volleyball. Jump performance is influenced by various factors that affect this indicator, such as body balance, upper and lower body coordination, as well as explosive power. The purpose of this study was to investigate the relationship between height, push-off angle, explosive power, and jumping performance in volleyball student athletes. Material and Methods: The method used was a correlational, 7 male volleyball student athletes as samples (age = 21.00 ± 1.732 years, height = 167.86 ± 1.864 cm). Sampling technique used is purposive sampling, Shapiro-Wilk and Levene's test to determine normality and homogeneity. Data calculations were processed using the help of IBM SPSS version 26.0., with decision making p &lt; 0.05. Results: Variable Push-Off Angle and Explosive Power show significant results (p &lt; 0.05). The Pearson correlation value for Push-Off Angle is -0.781, while the correlation value for Explosive Power is 0.908. Conversely, the variable Height does not show significant results (p &gt; 0.05), with a Pearson Correlation value of -0.334. The findings indicate that the aspect of Explosive Power provides a significant contribution with a positive relationship. This is followed by the aspect of Push-Off Angle, but the results show that this aspect provides a moderate contribution with a negative relationship. Additionally, the aspect of Height shows a negative relationship and a low contribution value. Conclusions: The Study’s findings conclude that Push-Off Angle and Explosive Power have a significant correlation and play a crucial role in enhancing Jump Performance. However, Body Height does not exhibit a significant correlation with Jump Performance. These findings also conclude that the aspect that plays a crucial role in jump performance is explosive power.

The Effects of an 8-Week Strength Training Toward the Specific Preparation Phase on Male Volleyball Athletes’ Performance

Background. Training programs are part of training management that need to be properly and correctly prepared and implemented. Study Purpose. The aim of the study was to evaluate the effects of an 8-week program of resistance training, carried out at a specific preparation phase, on the performance of male junior volleyball athletes. Materials and methods. This study was conducted as experimental research, with a sample of 24 male volleyball athletes ([mean ± SD] age: 17.96 ± 1.23 years; body weight: 75.56 ± 7.80 kg; height: 180.46 ± 7.14 cm; body fat: 17.62 ± 3.36%) who were randomly divided into experimental group (EG): n = 12 and control group (CG): n = 12. The training program lasted for eight weeks and took place at a specific preparation phase. Results. There was a significant increase in the indicators handgrip dynamometer left (p&lt;0.014), handgrip dynamometer right (p&lt;0.001), vertical jump (p&lt;0.001), sit-and-reach test (p&lt;0.000), leg dynamometer (p&lt;0.000), and back dynamometer (p&lt;0.001) in the experimental group after being given strength training treatment for eight weeks. Conclusions. When strength training is included in volleyball training, it can increase the performance in power, strength, and flexibility, especially when carried out at a specific preparation phase. Incorporating targeted stimuli, such as strength training, into training sessions appears to be a secure method of training for this age group and may help to contribute to continuous and gradual improvements in neuromuscular adaptation.

Review Of Basic Techniques In Club Volleyball, Pekanbaru City Transportation Office

The purpose of this research is to see the basic technical skills of volleyball Pekanbaru City Transportation Department club. Based on the results of observations made at the Pekanbaru City Transportation Service club, several problems were found, including passing due to the ball being hit on the finger incorrectly, errors occurring in serving, not following the rules that have been explained so that the ball being served does not reach the opponent's court. or less than optimal, when smashing, the strength of the arm muscles and handling of the ball when smashing is less accurate, and the player's discipline must be improved in carrying out training more seriously and following all the rules. The tests used in this research used the under serve, under pass and smash tests in volleyball. The sample in this study was 12 people. From the results of tests carried out on volleyball athletes from the Pekanbaru City Transportation Service club, results were obtained in the " Good " category

New hand dynamometer activforce isometric muscle activation on single joint muscle force of volleyball players

Isometric muscle activation of single joint to volleyball players is critic on sport performance to produce potential muscle force, however isometric measurement limited in isokinetic muscle activity measurement of volleyball players. Indeed, hand dynamometers commonly use in various body isometric force. Professional volleyball players age 16.23 ± 0.59 yr, body mass 60.22 ± 4.64 kg, hight 1.69 ± 0.04 m participated to peak and average isometric force measurement over 8 week pre and post test. Accordingly, single joint muscle force production measurement of volleyball players tested on isometric muscle activation using a new hand dynamometer activforce 2. Isometric muscle activation tests consisted of 24 body region from upper and lower compartment. For this isometric muscle action test detected on peak force outcomes (SEM: 37.90; CV: 1.79) and average force outcomes (SEM: 33.62; CV: 1.84). The high isometric muscle action joint loading performing mechanical test application recommended on athletic population to using isometric potential high contraction model by strength training performance separately in-season and off-season measurement modeling. Conclusion, peak and average force production progressive isometric modeling of volleyball athletes worked to current sport–health condition. As out, conclusion must be advanced isometric force measurement proper work in sport-specific tasks. The proper isometric force must be repeat sport performance outcome in different sport modalities.

How to Quickly and Affordably Reduce Corneal Neovascularization

Abstract&#x0D; Introduction : Fine needle diathermy (FND) is one of the treatment modalities for corneal neovascularization (CoNV). Occlusion of the CoNV will reduce vascular leakage, thus preserving visual acuity. This case report presents FND as a treatment for CoNV due to ocular rosacea.&#x0D; Case Illustration : A 25-year-old volleyball athlete came to Cicendo Eye Hospital after experiencing blurry vision for a week, followed by flushing on the face. A general examination revealed telangiectasia and pustules on the central face (Figure 1). Visual acuity was 0.2 RE. A slit-lamp examination revealed hyperemiain the lid margins, oedema, and superficial-stromal neovascularization on the cornea (Figure 2). The patient was diagnosed with blepharo-kerato-conjunctivitis on RE due to ocular rosacea. The patient then underwent FND (Figure 3). The procedure was performed by using a 10.0-gauge needle inserted in the corneal stroma along the CoNV. The vessels were occluded by conducting monophasic diathermy at a power of 1 mA (Figure 4). On the 5th day, corneal oedema and neovascularization were reduced, and visual acuity improved to 0.4 ph 0.5 (Figure 5).&#x0D; Discussion : Corneal neovascularization may affect corneal transparency and thus reduce visual acuity. FND is relatively affordable and widely available. Compared to another modality, FND has not been widely performed to treat CoNV. A literature search using PubMed or Google Scholar found few case reports or reviews regarding successful cases of FND.&#x0D; Conclusion : Fine needle diathermy is a safe and effective treatment for CoNV due to ocular rosacea. Further studies should be conducted to evaluate the safety and long-term efficacy of FND.

Determining intracortical, corticospinal and alpha motoneurone excitability in athletes with patellar tendinopathy compared to asymptomatic controls.

Lower capacity to generate knee extension maximal voluntary force (MVF) has been observed in individuals affected with patellar tendinopathy (PT) compared to asymptomatic controls. This MVF deficit is hypothesized to emanate from alterations in corticospinal excitability (CSE). The modulation of CSE is intricately linked to the excitability levels at multiple sites, encompassing neurones within the corticospinal tract (CST), intracortical neurones within the primary motor cortex (M1), and the alpha motoneurone. The aim of this investigation was to examine the excitability of intracortical neurones, CST neurones, and the alpha motoneurone, and compare these between volleyball and basketball athletes with PT and matched asymptomatic controls. Nineteen athletes with PT and 18 asymptomatic controls participated in this cross-sectional study. Transcranial magnetic stimulation was utilized to assess CST excitability, corticospinal inhibition (silent period, and short-interval cortical inhibition). Peripheral nerve stimulation was used to evaluate lumbar spine and alpha motoneurone excitability, including the evocation of lumbar-evoked potentials and maximal compound muscle action potential (MMAX ), and CSE with central activation ratio (CAR). Knee extension MVF was also assessed. Athletes with PT exhibited longer silent period duration and greater electrical stimulator output for MMAX , as well as lower MVF, compared to asymptomatic controls (p < 0.05). These findings indicate volleyball and basketball athletes with PT exhibit reduced excitability of the alpha motoneurone or the neuromuscular junction, which may be linked to lower MVF. Subtle alterations at specific sites may represent compensatory changes to excitability aiming to maintain efferent drive to the knee extensors.

Proximal Muscle Weakness in a Collegiate Volleyball Athlete.

Proximal Muscle Weakness in a Collegiate Volleyball Athlete.

Prevalence of sunscreen use and sunburn in Greek athletes: a cross-sectional study.

Athletes participating in outdoor sports are in a high-risk category for prolonged sun exposure. This study investigates whether swimmers and beach volleyball athletes adopt appropriate measures to protect their skin from the sun. Sunscreens play a key role in protecting the skin from solar radiation and preventing premature aging. The study assesses the frequency of sunscreen use and the incidence of sunburn among athletes. Athletes completed a self-administered questionnaire regarding their sun protection and exposure habits. Participants aged 9 to 60 years, engaged in swimming (N.=1047) and beach volleyball (N.=785), were included in this study. In the group of swimmers (N.=858), a notable percentage never used sunscreen, and among those who did, (N.=137), natural products were predominantly applied. Gender differences revealed a significantly higher sunscreen usage (P<0.001) among female swimmers compared to males. Among beach volleyball athletes, sunscreen use was notably higher (90%), with 55.6% applying natural sunscreen and 44.4% opting for non-natural alternatives. Regarding the incidence of sunburn, the occurrence among both male and female swimmers was observed to be very low. Among those with sunburn, females exhibited a significantly higher frequency than males (P<0.001). Conversely, in beach volleyball athletes, sunburn affected a higher percentage of males (49.8%) than females (43.9%). Sunscreen utilization is notably insufficient among athletes, reflecting a limited awareness of the potential risks associated with sun exposure, even though they frequently suffer from sunburn. This heightened susceptibility places them at an increased risk of developing skin lesions. Initiating and disseminating awareness campaigns that specifically emphasize the importance of sunscreen use within the outdoor sports community is imperative.

Enhancing Volleyball Athlete Performance: A Comprehensive Review of Training Interventions and Their Impact on Agility, Explosive Power, and Strength.

Volleyball is one of the most globally renowned sportsin terms of global popularity. The game is a team sport that both men and women can participate in. The gameplay relies heavily on physical activities such as jumping, landing, and quick movements, often causing strain on the musculoskeletal system and leading to injuries. For this reason, agility training is crucial to improving a player's ability to change direction swiftly as and when required by the gameplay. Although it is relatively safer than other team sports, actions like jumping, blocking, and spiking can lead to potential injuries. Properly monitoring the training loads and injury prevention during training should be the major focus in formulating a holistic training methodology in volleyball training. The main goal of this literature study is to evaluate the impact of various training interventions on agility and other performance parameters specific to volleyball players. The range of research approaches and interventions described in this literature review highlights the significance of agility in volleyball training. In many studies, the use of tailored training programs for volleyball has been shown to have positive effects on agility, strength, and jump performance. Although there are limitations to the study design and sample size, the findings from this review necessitate the need for better scientifically informed training programs to reduce injury risk while enhancing player's overall performance potential. To conclude, the current literature review highlights the importance of agility training in volleyball, providing insights into effective training strategies and highlighting the low quality of evidence, suggesting the need for well-structured research on the topic.

Analysis and comparison of psychological, physical, and personality traits of athletes of weightlifting, swimming, boxing, athletics, soccer, volleyball, and basketball

This study aims to describe and explore the psychological, physical, and personality traits of athletes in competitive sports in seven different sports: weightlifting, swimming, boxing, athletics, soccer, volleyball, and basketball. A total of 118 athletes (80 men, 38 women with a mean age of 25.05 ± 6.9) were selected from these seven categories. Additionally, the anthropometric measurement consists of height, weight, and body mass index. At the same time, physical ability is made up of five components: flexibility, arm muscle strength, abdominal muscle strength, leg muscle power and aerobic endurance. Psychological ability and personality characteristics were also measured using the Inventory of Psychological Abilities for Sport and the Athlete Personality Inventory. There were significant differences in the six variables (p&lt;0.01), but not in the other variables (p&gt;0.05). The six variables include height, body mass index, arm and abdominal muscle strength, leg muscle power, and aerobic endurance with values of 3.052 and 0.008 (p&lt;0.01), 3.497 and 0.003 (p&lt;0.01), 9.822 and 0.001 (p&lt; 0.01), 11.855 and 0.001 (p&lt;0.01), 52.747 and 0.001 (p&lt;0.01), and 11.298 and 0.001 (p&lt;0.01). However, psychological variables and personality characteristics were not significantly correlated with other variables. The anthropometric and physical aspects of the athletes tended to have differences depending on the sport. However, the psychological variables and personality characteristics had no relationship with the physical and anthropometric aspects. Este estudio tiene como objetivo describir y explorar los rasgos psicológicos, físicos, y la personalidad de los deportistas en los deportes de competición en siete deportes diferentes: levantamiento de pesas, natación, boxeo, atletismo, fútbol, voleibol y baloncesto. Se seleccionaron un total de 118 deportistas (80 hombres, 38 mujeres con una edad media de 25,05 ± 6,9) de estas siete categorías. Además, la medida antropométrica consta de altura, peso e índice de masa corporal. Al mismo tiempo, la capacidad física se compone de cinco componentes: flexibilidad, fuerza de los músculos del brazo, fuerza de los músculos abdominales, potencia de los músculos de las piernas y resistencia aeróbica. La capacidad psicológica y las características de personalidad también se midieron utilizando el Inventario de Habilidades Psicológicas para el Deporte y el Inventario de Personalidad del Atleta. Hubo diferencias significativas en las seis variables (p&lt;0,01), pero no en las demás variables (p&gt;0,05). Las seis variables incluyen altura, índice de masa corporal, fuerza de los músculos de los brazos y abdominales, potencia de los músculos de las piernas y resistencia aeróbica con valores de de 3,052 y 0,008 (p&lt;0,01), 3,497 y 0,003 (p&lt;0,01), 9,822 y 0,001 (p&lt;0,01), 11,855 y 0,001 (p&lt;0,01), 52,747 y 0,001 (p&lt;0,01), y 11,298 y 0,001 (p&lt;0,01). Las otras cuatro variables, peso, flexibilidad, capacidades psicológicas y rasgos de personalidad no mostraron diferencias significativas (p&gt;0,05). Las variables de resistencia aeróbica, en general, tuvieron relación significativa con las variables antropométricas y otros aspectos físicos. Sin embargo, las variables psicológicas y las características de personalidad no se correlacionaron significativamente con otras variables. Los aspectos antropométricos y físicos de los deportistas tendieron a tener diferencias según el deporte. Sin embargo, las variables psicológicas y las características de personalidad no tuvieron relación con los aspectos físicos y antropométricos.

Comparison of the Vertical and Horizontal Components of the Ground Reaction Force of Patients with Anterior Cruciate Ligament Reconstruction and Healthy Individuals during Walking

Introduction: The aim of this research was to compare the vertical, medial-lateral and anterior-posterior components of ground reaction force after anterior cruciate ligament reconstruction with the healthy individuals during walking.&#x0D; Methods: This was an analytic cross sectional research. The participants of this research included 46 football and volleyball athletes, who were divided into two groups of individuals with anterior cruciate ligament reconstruction (ACLR) and healthy individuals. A force plate was employed to evaluate the components of the ground reaction force while walking.The data were statistically analysed using independent t test and SPSS version 16 software.&#x0D; Results: The results related to the vertical component of ground reaction force showed that the participants with anterior cruciate ligament reconstruction applied more force to the ground during heel strike and toe-off compared to healthy individuals, although the difference between the two groups was not significant (p=0.09 and p=0.35), but this difference was greater during heel strike. Likewise, the results related to the horizontal components of the ground reaction force showed that participants with anterior cruciate ligament reconstruction applied more force to the ground in all horizontal components of the ground reaction force, but the biggest difference between the two groups was in the first 20% of the stance phase and in the posterior (p&lt;0.007) and lateral (p&lt;0.02) directions. This difference between the two groups was significant.&#x0D; Conclusion: The results of the research showed that the most important difference between the two groups occurred in the first 20% of the stance phase. Although among the 6 measured components, only the posterior (p &lt; 0.007) and medial (p &lt; 0.02) ground force components were significant.

Diagnostic value of shear-wave elastography for patellar tendinopathy in female volleyball and basketball athletes: a cross sectional case control study

ABSTRACT Objectives We aim to investigate the accuracy of shear-wave elastography (SWE) in diagnosing patellar tendinopathy in female volleyball and basketball players. In addition, we compared different parts of the patellar tendon and investigated the effects of different knee angles on elastography measurements. Methods This cross-sectional case–control study evaluated 63 female athletes from professional basketball and volleyball teams (NCT06199583). Patellar tendinopathy diagnoses were made using clinical and ultrasonographic criteria. SWE measurements were taken at 30-degree knee flexion and extension. Rectangular regions of interest boxes were placed in three different parts of the tendon (proximal, middle, distal). The global SWE value was calculated by taking the mean of measurements in the three parts. Receiver operating characteristic (ROC) curves were used to identify significant cutoff points for SWE, and 2 × 2 tables were generated to determine sensitivity and specificity. Results Thirteen (20.6%) of the 63 athletes were diagnosed with patellar tendinopathy. The ROC curves have identified different cutoff scores for SWE measurements. The SWE score of 130.75 from the proximal part showed the highest sensitivity of 89% and specificity of 80% (p < 0.001) with a 4.45 likelihood ratio at the 30-degree knee flexion. The likelihood ratio is 1.5 at a 30-degree angle and 1.65 at a 0-degree angle when measuring the entire tendon, whereas other portions indicate a ratio ranging from 1.12 to 1.73. Conclusions Shear-wave elastography is a reliable evaluation method for diagnosing patellar tendinopathy. It has more accuracy when applied to the proximal part and at 30-degree knee flexion compared to measurements taken at knee extension and other parts of the tendon.

Is There a Relationship Between Birth Quartile and Vertical Jump Performance Among Young Male Elite Volleyball Athletes?

Vertical jump is an important skill that influences volleyball performance. In this study, we analyzed the relationship between vertical jump performance and birth quartile of Brazilian male youth volleyball players. We calculated chi-square goodness-of-fit tests to compare the athletes' birthdate distributions in quarters of their birth years (Q1, Q2, Q3, and Q4) according to player age categories (U17, U18, U19, and U21). We calculated one-way ANOVAs to compare spike jump and block jump heights of players born in different quarters of the same year. Overall, we found a relative age effect (i.e., more players with birth dates early in the birth year) in U17 (p < .001), U18 (p < .001), U19 (p < .001), and U21 (p = .04). Regarding vertical jump performance, U18 athletes born in Q2 reached higher spike jump heights (p = .006) and block jump heights (p = .002) than athletes born in Q4, and U19 athletes born in Q1 reached higher block jump heights than athletes born in Q3 (p = .049). There were no significant differences in vertical jump performance across birth quartiles among U17 and U21 athletes. Thus, a relative age effect was present in all age categories but not always reflected in vertical jump performance. Volleyball coaches and policymakers are still advised to employ strategies to ensure fairer opportunities for players born later in the year of their eligibility dates, as we found RAE to be sometimes, but not always, related to higher spike or block jump heights even among these older adolescents and young adult athletes.