Clinical Research Directory

THE EFFECT OF DIRECTED INVENTION METHOD STUDIES ON BASIC SKILLS AND REACTION TIME IN VOLLEYBALL

Aim: The aim of this study was to examine the effects of the directed invention method on basic volleyball skills and reaction time. Materials and Methods: A total of 40 university students with no previous volleyball training experience, enrolled at Bayburt University during the fall semester of the 2024-2025 academic year, participated in the study. Participants were divided into an experimental group (n = 20), which received the directed invention method combined with traditional volleyball training, and a control group (n = 20), which received traditional volleyball training alone. Each group consisted of 10 male and 10 female students. Both groups participated in an 8-week training program. A quasi-experimental pretest-posttest control-group design was used. Basic volleyball skills were assessed using a rating scale and direct observation, while reaction time was measured using the BlazePod system and wireless light disks. Descriptive statistics and normality tests were performed. The Mann-Whitney U test was used for between-group comparisons, and the Wilcoxon signed-rank test was used for within-group comparisons of non-normally distributed data. Statistical analyses were performed using SPSS version 26.0.

Acute Effects of Kinesiology Taping on Performance in Volleyball Players

Kinesiological tape is frequently used to provide support for injured muscles and joints, enhance fascial function, inhibit pain-inducing stimuli, and improve blood and lymph circulation. However, there is no consensus among researchers and practitioners regarding kinesiological taping, particularly its application to improve athletic performance. This study aimed to investigate the acute changes in functional performance of volleyball players who underwent kinesiological taping. Designed as a randomized controlled experimental study, it planned to include 24 licensed female volleyball players from Anadolu Marmara Sports Schools. Players meeting the inclusion criteria were randomized into kinesiological tape (n:12) and sham (dummy-ineffective) tape (n:12) groups. The assessment will consist of a general warm-up program followed by the single-arm hop test for upper extremity strength, speed, and stability; the closed kinetic chain upper extremity endurance test for strength and endurance; and the medicine ball throw test for functional strength. Following the initial assessment, tests will be repeated immediately after facilitative taping of the pectoralis major and anterior deltoid muscles of the athletes. SPSS 24 statistical program will be used for data analysis. Continuous variables will be presented as mean ± standard deviation, and qualitative variables as number and percentage (%). If the assumptions for parametric tests are met, the Independent Samples t-test will be used for comparing independent groups, and the Paired Samples t-test will be used for comparing dependent groups. If the assumptions for parametric tests are not met, the Mann-Whitney U test will be used for comparing independent groups, and the Wilcoxon test will be used for comparing dependent groups. Statistical significance will be accepted at p≤0.05. This study is expected to contribute to performance-enhancing practices in volleyball players by providing evidence-based data on the application method and effectiveness of kinesiological taping for functional performance.

Acute Effects of Bilateral Versus Unilateral Isometric Conditioning Activity on Jump Performance in Volleyball Players

This randomized crossover trial investigates the acute effects of bilateral and unilateral isometric conditioning activity on bilateral and unilateral jump performance in highly trained male volleyball players. Fourteen athletes will complete three experimental conditions in randomized order: bilateral isometric squat conditioning activity (BI), unilateral isometric squat conditioning activity (UNI), and a control condition consisting of low-intensity treadmill walking (CTRL). In both isometric conditions, participants will perform three sets of three maximal 3-second contractions, with 3-minute recovery intervals between sets. Jump performance will be assessed before each experimental condition and at 4, 8, and 12 minutes afterward using bilateral countermovement jumps and single-leg jumps performed separately with each lower limb. The primary aim of the study is to determine whether the mode of isometric conditioning activity, unilateral versus bilateral, influences the magnitude and time course of acute changes in jump performance. An additional objective is to assess whether the effects of the conditioning activity differ between bilateral and unilateral jumping tasks.

Effects of Different Nap Durations on Volleyball Performance and EEG Activity Following Mental Fatigue

Mental fatigue is known to impair cognitive and physical performance in athletes, but the effectiveness of different nap durations in counteracting these effects remains unclear. The purpose of this randomized crossover study is to investigate the effects of mental fatigue and different nap durations (20, 40, 60, and 90 minutes) on volleyball-specific performance and electroencephalographic (EEG) activity in trained male volleyball players. Mental fatigue is induced using a 15-minute Stroop task. Performance outcomes include the Volleyball Agility Test (VAT) and Countermovement Jump (CMJ), while cortical activity is assessed using resting-state EEG recordings. The findings are expected to improve understanding of the neurophysiological mechanisms underlying mental fatigue and recovery and to provide evidence-based recommendations regarding optimal nap duration for athletes.

Effects of Cognitive Training on Executive Functions and Decision-Making in Adolescent Female Volleyball Players

This randomized controlled trial aims to evaluate the effects of a four-week tablet-based cognitive training program on executive functions and on-court decision-making performance in adolescent female volleyball players. Fifty licensed female volleyball players aged 12 to 14 years were randomly assigned to either an intervention group or a control group. The intervention group received cognitive training three times per week in addition to routine volleyball training, while the control group continued routine training only. Executive functions were assessed using the Stroop Test, Trail Making Test-A, Go/No-Go Test, and 2-Back Test. Volleyball-specific decision-making performance was evaluated using a video-based temporal occlusion test. The study investigates whether improvements in executive functions following cognitive training transfer to sport-specific decision-making performance.

Effects of Myofascial Release Technique on Mobility, Sensorimotor Function and Performance in Volleyball Players

Sports that require overhead activities (volleyball, tennis, basketball) include components such as rapid displacement, strength and movement control.Volleyball is also called as an overhead sport in terms of the way it is played. In the realization of these sports; Sub-parameters such as proprioceptive sense, strength, throwing rate, flexibility play a role. During these activities, the shoulder and elbow joints are overloaded. To meet this load, the joint must provide the necessary mobility and stability. Proprioceptive sense in increasing the quality and width of movement as well as providing dynamic joint stability in overhead sports; Increasing the range of motion of the joint, reducing muscle stiffness and thus increasing flexibility are effective in providing mobility. That's why it's important to develop them. Likewise, muscle strength should be increased in order to maintain movement performance and prevent injuries. The use of myofascial release techniques as an exercise method has increased in recent years. Application; The effects on parameters such as strength, performance and flexibility were investigated. Studies have focused more on the lower extremities and acute effects. There is no study on the subject examining proprioceptive sensation in volleyball players in the upper extremity. Therefore, our aim is to examine the chronic effects of the application on shoulder and elbow joint mobility, sensorimotor function and performance.

Effects of SVT on Balance and Proprioception

This study was conducted to scientifically investigate the effects of a training program utilizing stroboscopic glasses on balance and proprioceptive performance in adolescent male volleyball players. A quantitative research approach was adopted, and a pre-test-post-test experimental design with a control group was employed to rigorously examine the cause-effect relationships between variables. The study sample consisted of 30 adolescent male volleyball players aged between 12 and 18 years. Inclusion criteria required participants to have been licensed volleyball players for at least one year and to be regularly engaged in training sessions at least twice per week. To ensure objectivity, participants were randomly assigned, using a computer-based randomization method, into an experimental group (n = 15) and a control group (n = 15). The experimental intervention lasted six weeks and was specifically designed to complement volleyball-specific technical training. Both groups participated in training sessions twice per week, at the same time of day and with identical training volumes. Within the stroboscopic visual stimulus protocol, athletes in the experimental group used stroboscopic glasses continuously for a total of 2.5 minutes during each training session. This 150-second exposure was determined to encourage athletes to rely more heavily on proprioceptive and vestibular mechanisms under conditions of reduced visual input. The glasses, equipped with LED-filtered lenses that alternated between transparent and opaque states at specific frequencies, manipulated the transmission of visual information to the central nervous system, thereby forcing athletes to maintain motor control with limited visual input. In contrast, the control group completed the same 2.5-minute segment and the entire training protocol under normal visual conditions, without any visual restriction. All training sessions were conducted in an indoor sports facility under the supervision of an experienced coach, ensuring a controlled environment free from external disturbances. Athletes' fatigue levels, adherence to the protocol, and overall health status were monitored on a session-by-session basis. Following the completion of the six-week intervention, both groups underwent post-intervention assessments to determine the effects of the training program on performance parameters. Dynamic balance performance was evaluated using the Y Balance Test, a widely accepted and validated assessment tool in the literature. During testing, participants performed barefoot while maintaining single-leg stance on the dominant limb and reaching as far as possible with the contralateral limb in the anterior, posteromedial, and posterolateral directions. The best score from three trials in each direction was recorded. All reach distances were normalized to limb length to minimize the influence of anthropometric differences. Proprioception was assessed through joint position sense and movement perception tests. During these assessments, participants' vision was occluded to eliminate visual input and isolate somatosensory function. The extremity was passively positioned at predetermined target angles by the researcher, and participants were then asked to actively reproduce the same position. The absolute angular difference between the target and reproduced positions was measured in degrees using a goniometer and recorded as the "proprioceptive error score." Data collection was completed in two phases: baseline measurements conducted prior to the intervention (pre-test) and follow-up measurements performed after the six-week training program (post-test). The findings of this study indicate that conventional volleyball training significantly improves both static and dynamic balance performance. However, stroboscopic visual training appears to produce more pronounced and selective improvements in proprioceptive awareness. These results suggest that, rather than directly enhancing overall performance outcomes, stroboscopic training may serve as an effective tool for targeting sensory-motor subcomponents that underpin athletic performance.

The Effect of Cognitive Dual-Task on Athletic Performance Parameters in Volleyball Players With and Without Chronic Ankle Instability

The aim of this study is to investigate the effect of the cognitive dual-task on athletic performance parameters in volleyball players with and without chronic ankle instability. In addition, it will examine how a pathology in the lower extremity affects upper extremity function.

BFR Rope Training in Male Volleyball Players

The study will be conducted during the preparatory period of the volleyball players and will span eight weeks. Throughout this period, athletes will continue their regular volleyball training four days per week, while the experimental group (n = 10) will perform rope training with blood flow restriction (BFR) twice per week, and the control group (n = 10) will perform the same rope training without BFR. Assessments will be carried out at the beginning of the 8-week period (pre-test) and at the end of the intervention (post-test). For both groups, all exercises will target the upper-extremity muscle groups. During the study, participants will be instructed to avoid consuming any medications, engaging in additional strenuous physical activities, and using any techniques or ergogenic aids that might influence the results. In both testing sessions, a standardized warm-up protocol will be implemented, consisting of a 5-minute treadmill run at 9 km/h on a Sprint Runner device (Hoggan Health Industries, Draper, UT), followed by 3 minutes of light full-body stretching. This warm-up procedure will be applied consistently across both groups to ensure standardization.

Effects of Combined Training Protocol in Volleyball Players

The 12-week training will take place during the preparation period. At the beginning and end of the 12-week period, vertical jump test, 60 seconds countermovement jump (CMJ) test, change of direction (T-Agility) test, sprint test, YO-YO (level-1) test will be applied in terms of performance test. In terms of skill testing, service test and spiking test protocols will be applied. Players will perform plyometric (PL) or jump rope (JR) training with the same amount of total training time in each training session. Rating of perceived exertion (RPE) will be obtained using (CR6-20). All players will also complete the short form of the physical activity enjoyment scale (PACES).