Male Volleyball Players Research Articles

Effects of Mild Fatigue on Biomechanics of Single Leg Landing in Young Male Volleyball Players

Objective: To investigate the effects of mild fatigue on the biomechanics of the lower limbs of young male volleyball players while performing single leg landing tasks. Methods: A total of ten young male volleyball players were recruited as participants in this study. After the single leg landing was performed, we compared the performance between those with and without fatigue (post- and non-fatigue, respectively). Kinematics and kinetics were collected using instruments, and related captured data were imported into OpenSim to analyze the hip, knee, and ankle joints. Results: We found that the ankle dorsiflexion angle at initial contact was significantly decreased in the post-fatigue group compared to the non-fatigue one. Meanwhile, the peak gluteus maximus force, peak gluteus medius force, peak tibialis posterior force, and peak gastrocnemius force significantly increased. There were no significant differences in the hip and knee joint flexion angles as well as the quadriceps and biceps femoris long head forces between the two groups. Conclusions: Mild fatigue can affect the performance of single leg landing, and players need to control the lower limbs by generating a higher muscle force to cope with the instability induced by fatigue. In a fatigued state, following initial contact with the ground, a decreased ankle dorsiflexion angle necessitates an increase in gastrocnemius and tibialis posterior muscle force to maintain stance during landing.

Biomechanic Differences Between Anticipated and Unanticipated Volleyball Block Jump: Implications for Lower Limb Injury Risk

Volleyball is a high-intensity sport characterized by repetitive jumping, sudden directional changes, and overhead movements, all of which significantly increase the risk of injuries, particularly to the shoulders, knees, and ankles. Despite the frequency of injuries caused by actions like blocking and spiking, there has been limited research focused on the specific biomechanical risk factors unique to volleyball. This study aimed to investigate the lower limb biomechanics during block jumps in both the dominant and non-dominant directions, under both anticipated and unanticipated conditions, in fifteen elite male volleyball players. Kinematic and kinetic data from the ankle, knee, and hip joints were recorded. Our results revealed statistically significant differences between the dominant and non-dominant directions at the ankle, knee, and hip joints. The non-dominant direction exhibited a greater ankle dorsiflexion angle and velocity, as well as higher knee flexion angle, velocity, moment, power, and abduction moment, along with increased hip flexion angle and power. Additionally, unanticipated movements led to increases in vertical ground reaction force (vGRF), hip extension moment, and flexion power, while ankle dorsiflexion plantarflexion velocity and knee flexion power decreased. It appears that movements in the dominant direction were stiffer and less cushioned, potentially increasing the risk of injury. While the non-dominant direction provided better shock absorption, it also elevated the knee valgus moment, which could increase the load on the knee. Furthermore, in unanticipated situations, athletes with short reaction times, unable to quickly adjust their automated movement patterns, faced a higher risk of limb overuse, thereby increasing the likelihood of injury. In practice, coaches should consider differences in limb coordination and movement direction, incorporating unilateral preventive exercises to reduce the risk of injury.

Is the Rate of Force Development Produced in the Squat Jump a Reliable Metric and is it Related to Jump Height?

ABSTRACT This study aimed to analyze the intrasession reliability of the rate of force development (RFD) in different time windows in squat jumps (SJ) performed at different knee starting angles, and identify the relationship of RFD with vertical jump height (VJH). Twenty male volleyball and basketball players participated. Athletes randomly performed SJ from four different knee-flexion angles. The RFD was analyzed from six different windows, from force onset to instant peak force, in each position using the ground reaction forces. Reliability analysis was performed based on the intraclass correlation coefficient (ICC) and coefficient of variation (CV%); Spearman’s rho was used to test the relationship between RFD and VJH. The results demonstrated that RFD0-PF was the only variable assumed to be reliable, demonstrating an ICC > 0.84 and CV < 8.5% in all positions, and significant correlations between RFD metrics and VJH were observed at SJ70 and SJPREF. Some variables were underpowered due to the small sample size, as a limitation of the study.

Prevalence and associated factors of non-traumatic shoulder pain during spike and serve movements in male high school volleyball players: a cross-sectional study

BackgroundNontraumatic shoulder pain is a prevalent issue among male high school volleyball players, but its comprehensive assessment has been lacking in prior research, which often isolated specific aspects of shoulder function. This study aimed to identify contributing factors to shoulder pain in this population. HypothesisThe hypothesis posited that limited shoulder internal rotation (IR) range of motion (ROM), imbalance in rotator cuff muscle strength, intrinsic sensory disturbance, and joint stability are associated with shoulder pain in male high school volleyball players. Additionally, there was an anticipation that a substantial proportion of players would experience shoulder pain but refrain from reporting it to coaches. MethodsForty-nine male volleyball players aged 15-17 years were evaluated between February and June 2023. Questionnaires assessed the prevalence of shoulder pain during spiking and/or serving, as well as the frequency of reporting this pain to coaches. Various factors, including acromio-humeral distance, shoulder ROM, isometric strength, proprioception, joint stability (Upper Quarter Y-Balance Test), joint position sense, and upper extremity power (Seated Medicine Ball Throw Test; SMBT), were quantified. Logistic regression analyses was conducted to explore potential connections between these variables and shoulder pain. ResultsShoulder pain was reported by 39% of participants, but it was rarely communicated to coaches (95%). Jump serves (odds ratio 1.84, p=0.02) and reduced shoulder IR ROM (odds ratio 0.94, p=0.03) were associated with shoulder pain. ConclusionThis study provides crucial insights into the prevalence, severity, and associated factors of shoulder pain among male high school volleyball players. The findings underscore the importance of improving athlete-coach communication to facilitate early intervention and preventive measures. Significant associations were observed between the use of jump serves, reduced shoulder internal rotation range of motion, and shoulder pain, highlighting the relevance of specific volleyball techniques in injury prevention. These findings offer valuable guidance to coaches and trainers in developing interventions aimed at mitigating the risk of shoulder pain and enhancing player performance.

Effect of training in a sandy environment on foot morphology and function

BackgroundAthletes need to enhance their foot function to improve their performance and prevent injuries and disability. Although foot function is believed to be improved by stabilizing the body on an unstable surface (e.g., a sandy beach), there have been no relevant studies to our knowledge. Here, we identified the differences in foot and balance functions between beach volleyball and volleyball players and investigated the effects of sandy surface training. MethodsWe included six male beach volleyball players (BVB group) and six male volleyball players (VB group). The following six parameters were measured and compared between the groups: foot morphology, plantar surface perception, isometric ankle muscle strength, toe grip strength, static balance, and dynamic balance. ResultsThe BVB group had significantly higher values in sensation perception, isometric ankle dorsiflexion muscle strength, and toe grip strength in the standing posture, with significant intrinsic foot muscle dominance, compared to the VB group. ConclusionPlaying barefoot increases the amount of tactile information received from the surface of the sole, which may lead to enhanced sensory perception by the foot. In addition, owing to the unstable sandy surface, the intrinsic muscles of the foot and lower leg may strengthen to maintain balance; therefore, training on a sandy surface may lead to improved foot and balance functions.

Quantifying and analysing the angular momentum in volleyball jump serve during the aerial phase: relationship to arm swing speed.

In volleyball, the jump serve is a crucial and commonly used serving technique. Nonetheless, the angular momentum developed during the jump serve remains unexplored. The objectives of the current study were to determine the angular momentum manifesting during the airborne phase of the jump serve and to analyse the correlations between the angular momentum variables and arm swing speed. Three-dimensional coordinate data were obtained during the jump serves of 17 professional male volleyball players. Correlation and linear regression analyses were used to identify the angular momentum variables linked to the arm swing speed at ball impact (BI). The arm swing speed at BI exhibited significant correlations with the peak angular momentum of the attack arm (r = 0.551, p = 0.024), non-attack arm (r = 0.608, p = 0.011), non-attack leg (r = -0.516, p = 0.034), forearm (r = 0.527, p = 0.032), and hand (r = 0.824, p < 0.001). A stepwise regression model (R2 = 0.35, p = 0.043) predicted arm swing speed based on the peak angular momentum of the non-attack leg, forearm, and hand. The study results suggest that during the arm-acceleration phase, (1) increasing angular momentum with the non-attack leg helps maintain aerial body balance, thereby enhancing arm swing execution, and (2) controlling the magnitude and timing of the force exerted by the elbow and wrist is crucial for effectively transmitting angular momentum, contributing to an increase in arm swing speed.

A Comparison of the Instantaneous Effects of Spinal Manipulation and Mobilization Techniques Applied to L3 Level on Jumping, Agility, and Sprint Speed in Male Volleyball Players

A Comparison of the Instantaneous Effects of Spinal Manipulation and Mobilization Techniques Applied to L3 Level on Jumping, Agility, and Sprint Speed in Male Volleyball Players

Quantifying internal and external training loads in collegiate male volleyball players during a competitive season

BackgroundThe long-term monitoring of internal and external training load is crucial for the training effectiveness of athletes. This study aims to quantify the internal and external training loads of collegiate male volleyball players during the competitive season. The internal and external training load variables were analyzed across mesocycles and playing positions.MethodsFourteen participants with age of 20.2 ± 1.3 years, height of 1.81 ± 0.05 m, and body weight of 70.8 ± 5.9 kg were recruited. The data were collected over a 29-week period that was divided into four mesocycles: preparation 1 (P1, weeks 1–7), competition 1 (C1, weeks 8–14, including a 5-day tournament in week 14), preparation 2 (P2, weeks 15–23), and competition 2 (C2, weeks 24–29, including a 6-day tournament in week 29). Each participant wore an inertial measurement unit and reported the rating of perceived exertion in each training session. The internal training load variables included weekly session rating of perceived exertion, acute: chronic workload ratio, and training monotony and strain. The external training load variables included jump count and height and the percentage of jumps exceeding 80% of maximal height.ResultsC2 had the highest average weekly internal training load (3022 ± 849 AU), whereas P2 had the highest average weekly acute: chronic workload ratio (1.46 ± 0.13 AU). The number of weekly jumps in C1 (466.0 ± 176.8) was significantly higher than in other mesocycles. Weekly jump height was significantly higher in C1, P2, and C2. Internal training load was positively correlated with jump count (ρ = 0.477, p < 0.001). Jump count was negatively correlated with jump height (ρ = −0.089, p = 0.006) and the percentage of jumps exceeding 80% of maximal height (ρ = −0.388, p < 0.001). The internal and external training load variables were similar among different playing positions.ConclusionThe participants exhibited significantly higher internal training load in C2 and higher jump height after P1. A high jump count was associated with higher internal training load and lower jump height. Excessive jumps may result in fatigue and reduce height.

Muscle structure predictors of vertical jump performance in elite male volleyball players: a cross-sectional study based on ultrasonography.

The objective of this investigation is to examine the contribution of key muscle groups in the lower limbs to vertical jumping performance in elite male volleyball players. Specifically, the study focuses on the rectus femoris (RF), vastus lateralis (VL), and lateral gastrocnemius (LG), as well as exploring differences between attack jump and other vertical jump types. To achieve this, we employed B-mode ultrasound to evaluate the anatomical cross-sectional area (ACSA), muscle thickness (MT), pennation angle (PA), and fascicle length (FL) of the RF, VL, and LG in the participants. Fifteen elite male volleyball players were recruited as participants for this study. Jump heights were measured for four types of vertical jumps: attack jump (AJ), countermovement jump (CMJ), squat jump (SJ), and drop jump (DJ). We conducted regression analyses to assess whether the previously mentioned muscle structures could predict jump performance. Our findings reveal that the muscle structure of the RF does not exhibit any significant correlation with the height of any jump. However, VL-ACSA displays a significant and the most potent predictive effect on jump height for all four jump types (AJ: R 2 = 0.32, p = 0.001; CMJ: R 2 = 0.37, p = 0.005; SJ: R 2 = 0.52, p = 0.001; DJ: R 2 = 0.25, p = 0.021). Conversely, LG-FL only demonstrates a significant and stronger predictive effect on AJ jump height (R 2 = 0.18, p = 0.009). Combining VL-ACSA, LG-FL, and training age through multiple linear regression analysis resulted in a highly significant model for predicting AJ jump height (F = 13.86, R 2 = 0.73). Moreover, the model incorporating VL-ACSA and training age is also important for predicting CMJ, SJ, and DJ jump heights (F = 8.41, R 2 = 0.51; F = 13.14, R 2 = 0.63; F = 5.95, R 2 = 0.41; respectively). The muscle structure indicators in the lower limbs significantly predict jump performance among elite male volleyball players. However, different jump types are influenced by distinct indicators, particularly in the case of AJ, which is associated with LG-FL. This suggests that enhancing LG-FL may positively impact AJ ability, thereby emphasizing the importance of specificity in training. To optimize specialized jump performance in volleyball players, practitioners are advised to assess VL-ACSA and LG-FL and incorporate step-up and eccentric strength training targeting the calf muscles to yield considerable benefits.

The effects of fatigue on the relationship between ankle angle at initial contact and the knee and hip joints in landing: Assessing the risk of ACL injury

BackgroundAnterior cruciate ligament (ACL) injuries may correlate with lower limb angles and biomechanical factors in both dominant and non-dominant legs at initial contact (IC) post-landing. This study aims to investigate the correlation between ankle angles in three axes at IC and knee and hip joint angles during post-spike landings in professional volleyball players, both pre- and post-fatigue induction. Research questionTo what extent does fatigue influence lower limb joint angles, and what is the relationship between ankle joint angles and hip and knee angles at IC during the landing phase following a volleyball spike? MethodsUnder conditions involving the peripheral fatiguing protocol, the lower limb joint angles at IC following post-spike landings were measured in 28 professional male volleyball players aged between 19 and 28 years, who executed the Bosco fatigue protocol both before and after inducing fatigue. A paired t-test was utilized to compare the joint angles pre- and post-fatigue in both dominant and non-dominant legs. Furthermore, Pearson's correlation test was conducted to explore the relationship between ankle angles at IC and the corresponding knee and hip joint angles. ResultsThe findings of the study revealed that fatigue significantly increased hip external rotation and decreased knee joint flexion and external rotation in both the dominant and non-dominant legs (p < 0.05). Additionally, correlation analysis demonstrated that the ankle joint's positioning in the frontal and horizontal planes was significantly associated with hip flexion and external rotation at the IC, as well as with knee flexion and rotation (0.40 < r < 0.80). ConclusionFatigue increased hip external rotation and ankle internal rotation, weakening the correlation between these joints while strengthening the ankle-knee relationship, indicating a reduced hip control in jumps. This suggests a heightened ACL injury risk in the dominant leg due to the weakened ankle-hip connection, contrasting with the non-dominant leg.

POST-ACTIVATION PERFORMANCE ENHANCEMENT EFFECT OF TWO TUCK-JUMP PROTOCOLS WITH DIFFERENT VOLUMES ON 15-S VERTICAL JUMP PERFORMANCE

Post-activation performance enhancement is a principle that suggests that an acute bout of high intensity voluntary exercise will be followed by an improvement in strength, power, jump and speed of a subsequent task. This study aimed to investigate changes in 15 s repetitive vertical jump performance after one set (1 x 10 repetitions) or three sets (3 x 10 repetitions) of tuck jumps conditioning activity. Twelve male (age 21.6 ± 1.5 years) trained volleyball players participated in this study. The participants performed three experimental sessions with a randomized, counterbalanced, and crossover research design: a-) single set of tuck jump (SJ); b-) multiset of tuck jump (MJ); and c-) control (CON). Each experimental session was composed of a standard warm-up, conditioning activity, 5 minutes of rest, and then 15 s vertical jump test, respectively. Peak (p=0.029) and average (p=0.018) jump height, peak (p=0.029) and average (p = 0.007) power output were significantly greater in SJ than CON. No significant differences were observed in the fatigue index between conditions (p=0.657). Overall, there were no significant differences in any parameters between MJ and CON and between SJ and MJ (p&gt;0.05). These results showed that a SJ could improve repetitive vertical jump performance in trained male volleyball players, but caution should be given while using MJ before trainings or matches including activities with repetitive jumping.

The effects of circuit training versus high-intensity interval training on the endurance of volleyball athletes: a randomized controlled trial

Despite its intermittent nature, volleyball places significance on a high aerobic capacity, particularly evident in multiset games that demand sustained high-performance levels. Various training approaches exist to enhance the endurance of volleyball athletes. Thus, the fundamental aim of this research is to examine the contrasting effects of utilizing high-intensity interval training (HIIT) and circuit training methods to enhance volleyball athletes' endurance. The study used an Experimental group that partook in a HIIT training regime, and a Contrast group that undertook a Circuit training program. Thirty male volleyball players aged between 17 and 22 years (M=19.14; SD±1.61) were purposefully selected for the study and split into Contrast and Experimental groups of 15 each. At the beginning and end of the intervention programs both groups underwent physiological assessments for Maximum Oxygen Consumption (VO2max), Heart Rate Recovery (HRR), Peak Inspiratory Flow (PIF), Peak Expiratory Flow (PEF), and Force Vital Capacity (FVC). As result a meaningful Time x Group interaction for the VO2max, HRR, PIF, PEF and FVC was observed. This represents a significant improvement in the treatment group (p &lt; 0.001). No material change was observed in the comparison group. Findings revealed that the HIIT training approach outperformed the circuit training method in enhancing volleyball athletes' endurance. Consequently, it is should be beneficial for volleyball players to incorporate HIIT into their standard training regimens. Keywords: VO2max; physiology; sport; exercise; aerobic capacity.

The Validation of the Defensive Reactive Agility Test in Top-Level Volleyball Male Players: A New Approach to Evaluating Slide Speed Using Witty SEM

Aim: The aim of the study is to provide a new tool to measure the level of defensive agility objectively. Methods: The sample included 14 elite male volleyball players of the University of Nitra club (22.3 ± 5.7 years). Measurements consisted of body height (BH); body weight (BM); body mass index (BMI), and the defensive agility test (DRAT (test-retest)) with an interval of one week between the two tests using an electronic timer (Witty photocell) and Witty SEM lights (Microgate, ITA). The validation included assessing the equality of mean values in the test and retest (t-Student), effect sizes with Cohen’s d, analysis of variance (ANOVA), intraclass correlation coefficient determinations (ICC model), and random intercept correlation (Φ). Results: The results indicated no significant differences in both tests except for left movement (p = 0.0255). The ICC value of the test time was statistically significant (0.91); standard error of measurement (SEM = 0.02); repeatability coefficient (RC = 0.20); minimal difference (MD = 0.04). Effect sizes were trivial to small (d = ˂−0.05–0.17&gt;; right), medium (d = 0.35; backward) a large (d = −0.67; left). Conclusions: The DRAT test showed excellent reliability in total time (ICC = 0.91). Validation of the DRAT test’s consistency, reliability, accuracy and validity can help coaches make decisions about evaluating and monitoring defensive reactive agility performance in sports games.

Effects of the stretching program in male volleyball players with posterior shoulder tightness

BackgroundStretching programs are often used to improve muscle stiffness and thereby posterior shoulder tightness (PST); however, knowledge about their effects on the viscoelastic properties of muscles and performance is limited. ObjectiveThe aim of this study was to investigate the effects of a six-week stretching program on the viscoelastic properties of posterior shoulder muscles, shoulder functional performance and range of motion in volleyball players with PST. Study designA Randomized Controlled Trial. Level of evidenceLevel II. MethodsThe study was conducted in 34 male (aged 19–26) professional volleyball players with PST. They were randomly assigned to stretching and control groups. A stretching routine (combining sleeper stretch and cross body stretch exercises) was performed in the stretching group for six weeks. Measurements were taken during the first assessment and six weeks after the initiation of stretching for the following: shoulder external/internal rotation range of motion, spike velocity, single arm seated shot-put test, and infraspinatus– posterior deltoid muscle stiffness (by shear wave elastography). ResultsWhile the stretching group had statistically better results regarding increased shoulder internal rotation (p < 0.01), spike velocity (p = 0.02) and seated single arm shot put distance (p < 0.01), stretching did not have any effect on tissue stiffness. ConclusionsA 6-week program of sleeper stretch, and cross body stretch exercises improved shoulder internal rotation and functional performance. A clinically meaningful change in muscle mechanical properties cannot be detected after a 6-week stretching program.

A Comparison of Glutathione and Malondialdehyde Concentrations in Athletes Engaged in Certain Sports

Sports stimulate the body to adapt to physical activity, causing biochemical and functional metabolic changes in various systems and organs of the body due to exercise. Antioxidants and free radicals affect the biological activity of living organisms, leading to physiological changes in all body systems due to exercise. This study, conducted from December 2023 to February 2024, included 120 blood samples from male basketball (40), football (40), and volleyball (40) players ages 18-27 years, from the College of Physical Education and Sports Sciences at Tikrit University. Blood samples were collected ten minutes before and ten minutes after 70 minutes of exercise on the same day. The study found no significant differences in glutathione (GSH) and malondialdehyde (MDA) concentrations before and after exercise among the groups. The findings suggest that the type of sport (football, basketball, or volleyball) with an anaerobic system does not significantly affect antioxidant and fat peroxidation levels, though slight variations due to increased lactic acid in muscles were noted, leading to muscle fatigue and minor changes in GSH and MDA concentrations.

A New Training Load Quantification Method at Supramaximal Intensity and Its Application in Injuries Among Members of an International Volleyball Team.

Bouzigues, T, Maurelli, O, Imbach, F, Prioux, J, and Candau, R. A new training load quantification method at supramaximal intensity and its application in injuries among members of an international volleyball team. J Strength Cond Res 38(8): 1453-1463, 2024-The quantification of training loads (TLs) is essential for optimizing jump performance and reducing the occurrence of injuries. This study aimed to (a) propose a new method for quantifying TLs in explosive exercises, (b) determine the nature of the relationship between TLs dynamics and injury occurrence, and (c) assess a TL critical for training schedule purposes, above which the risk of injury occurrence becomes unacceptable. This study was conducted with 11 male volleyball players on a national team during a 5-month international competitive period. The proposed new method for quantifying TLs is based on a weighting factor applied to relative jumping intensities, determined by the number of sustainable jumps and their intensities measured by G-Vert accelerometer. The relationship between TLs dynamics and injury occurrence was assessed using a variable dose-response model. A high coefficient of determination was found between the maximum number of jumps possible and their intensities ( r2 = 0.94 ± 0.14, p < 0.001), indicating a strong physiological relationship between jumping intensities and the constraints imposed. The occurrence of injury was dependent on TLs dynamics for 2 players ( r2 = 0.26 ± 0.01; p < 0.001). The TL critical corresponded to 11 jumps over 80% of maximum jump height during games and approximately 130 jumps at <80% of maximal jump height. The present study proposes a new approach for quantifying supramaximal exercises and provides tools for training schedules and the prevention of volleyball injuries.

Pes planus level affects counter movement jump performance: A study on amateur male and female volleyball players.

The aim of this study was to investigate the effect of pes planus level on counter movement jump (CMJ) performance parameters in amateur female and male volleyball players. In this context, amateur volleyball players aged between 18 and 23 years actively playing in the university school volleyball team were included in the study. Pes planus levels of the participants were analyzed using the navicular drop test (NDT). My Jump Lab application was used for CMJ measurement. Within the scope of CMJ, the participants' jump height, force, relative force, power, relative power, average speed, take-off speed, impulse, and flying time were analyzed. According to the linear regression results between NDT and CMJ parameters, force in males (t = 12.93, P = .049) and average speed in females (t = -3.52, P = .017) were significantly associated with NDT. NDT was similar in men and women (P > .05). However, all CMJ parameters were highly different between genders (P < .001). In the correlation analysis between sport age and physical characteristics and CMJ parameters; height (r = .386, P = .046), weight (r = .569, P = .002), leg length (r = .389, P = .045), foot length (r =. 558, P = .005), foot width (r = .478, P = .018), force (r = .407, P = .039), impulse (r = .460, P = .018) parameters, and sport age. The results suggest that the average speed in females and force in males both significantly influenced NDT, highlighting the significance of both factors in predicting NDT scores. Moreover, all CMJ measures showed significant variations between genders, although the NDT scores did not. Furthermore, the correlation analysis demonstrated a strong correlation between a number of physical attributes and CMJ parameters, highlighting the multifaceted nature of athletic performance and indicating the possible impact of these attributes on CMJ results.

No effects of post-activation performance enhancement in elite male volleyball players under complex training

The aim of this study was to establish reliability of post-activation performance enhancement in three manners: (1) interday morning and afternoon reliability; (2) intraday morning and afternoon reliability; (3) intraday set-to-set reliability. Twelve elite male volleyball players experienced in resistance training performed four identical experimental sessions—two in the morning and two in the afternoon. During each session participants performed a mini complex training session—three sets of a conditioning activity (CA) (3 repetitions of a trap bar deadlift at 80% 1RM with 15% of accommodating resistance) and 90 s after a CA performed squat jump (SJ) with 4 min intra-set rest interval. The ANOVA with repeated measures was used to assess significance of the effect of a CA and ICC to assess reliability of measurements. The PAPE protocol was found to be ineffective to subsequently enhance JH on various occasions. Also, the results of this study suggest that the practitioners may effectively implement appropriately organized complex training as both intraday set-to-set (0.87 and 0.82 for morning sessions; 0.83 and 0.58 for afternoon sessions) and interday morning (0.67) and afternoon (0.8) reliabilities seem to be acceptable. However, introducing two CT sessions within one day is highly questionable as at the moment intraday morning and afternoon reliability is vague (0.88 and 0.48).

Effect of Level of Competition and Drill Typology on Internal and External Load in Male Volleyball Players During the Preseason Period.

This study aimed at evaluating the effect of level of competition and drill typology on loads during the preseason period in male volleyball players. Internal (percentage of peak heart rate [HR]and summated HR zone) and external (PlayerLoad per minute, total and high accelerations per minute [tACCmin and hACCmin], decelerations per minute [tDECmin and hDECmin], and jumps per minute [tJUMPmin and hJUMPmin]) loads were monitored across a 5-week preseason period in 12 Division 1 (age: 22.5 [3.9]y; stature: 188 [6.2]cm; body mass: 85 [11.6]kg; training experience: 9.4 [4.2]y) and 12 Division 2 (age: 20.7 [2.9]y; stature: 186 [6.2]cm; body mass: 77.8 [9.6]kg; training experience: 5.6 [2.3]y) male volleyball players. Furthermore, differences in load were assessed for each drill typology (warm-up, conditioning, technical, tactical, and integral). No effects (P > .05) of level of competition on the internal (except for summated HR zone, P = .05) and external loads (except for tJUMPmin, P = .002) were found. Differently, drill typologies showed an effect (P < .001) on all the investigated internal- and external-load measures. The main post hoc results revealed higher (P < .05) percentage of peak HR, summated HR zone, PlayerLoad per minute, and tACCmin in warm-up and conditioning drills, while higher (P < .05) hDECmin and hJUMPmin were found in tactical and integral drills. These results suggest thatvolleyball coaches use warm-up and conditioning drills when aiming at increasing the internal loads, PlayerLoad per minute, and tACCmin, while tactical and integral drills should be preferred to enhance the number of hDECmin and hJUMPmin.

Differences in the effects of plyometric squat jumps and bileg band training on leg strength increases in volleyball players of different gender

Background and purpose This study aims to determine differences in the effects of plyometric jumps, squats, and double leg band training on leg muscle strength gains in volleyball players of different genders. Material and methods This study was conducted at SMP Negeri 3 Karanganyar, Jalan Lawu No. 86, Ngarjosari, Karanganyar Regency, Central Java. This study was conducted over a six-week period, beginning February 5, 2024, and ending March 16, 2024, with meetings occurring three times per week on Mondays, Wednesdays, and Fridays. The experimental method is chosen to identify certain symptoms through an intervention carried out on a test sample. An experiment is a design that allows researchers to simultaneously study the effects of two or more types of experimental variables. Results After the analysis in the group of men, an increase in leg strength indicators was obtained as a result of the experiment by 2.468%. Meanwhile, in the group of women, an increase in leg strength indicators was obtained as a result of the experiment by 2.892%. Comparing the two female groups, there is a higher percentage increase than the male groups, which is 2.892% in females compared to 2.468% in males. Thus, the female group showed a more pronounced increase in results than the male group, with a significance of p &lt; 0.05. Thus, hypothesis 2 «there is a difference in the growth of leg muscle strength as a result of training using plyometric exercises in male and female students» is accepted. Conclusions Significant differences in the indicators of leg muscle strength increase in male and female volleyball players as a result of the use of special training were revealed. This is evidenced by the average increase in leg muscle strength in men by 2.468%, and in women by 2.892% at p &lt; 0.05.