Clinical Research Directory

Acute Effects of Shoulder Dynamic Taping in Competitive Volleyball Players

This randomized, sham-controlled study investigated the acute effects of shoulder Dynamic Tape on serve velocity, isometric shoulder rotator muscle strength, functional throwing performance, and athlete satisfaction in competitive volleyball players. Thirty athletes aged 18-35 years were randomly assigned to a Dynamic Tape group (n = 15) or a sham taping group (n = 15). In both groups, serve velocity, shoulder internal and external rotation strength, and functional throwing performance were assessed under taped and untaped conditions. The order of the assessment conditions was randomized to minimize order effects. Assessments under the taped condition were performed 45 minutes after tape application. Athlete satisfaction was evaluated following taping.

Core Strength Training, Anthropometry, and Postural Control in Youth Optimist Sailors

Optimist dinghy sailing is a highly demanding youth watersport characterized by prolonged, high-intensity isometric hiking postures and rapid dynamic weight shifts required to preserve boat trim, balance, and sail power output. The core (lumbar-pelvic-hip complex) functions as the central dynamic link in transferring kinetic forces between the lower limbs and trunk during continuous open-water maneuvers. This study is designed as a 12-week randomized controlled interventional trial to evaluate the effects of a periodized, circuit-based Core Strength Training (CST) program integrated into routine Technical Sailing Training (TST) compared to TST alone. Primary endpoints evaluate adaptations in the anthropometric profile (skinfold thickness, circumferences, muscle mass percentage) and postural control parameters (Center of Pressure displacement and sway velocity measured via computerized force platform posturography) in competitive youth Optimist sailors.

Effects of High-Intensity Interval Training (HIIT) on Physiological Responses in Alpine Skiers

The aim of this study was to investigate the effects of high-intensity interval training (HIIT) on anaerobic performance and cardiorespiratory responses in alpine skiing athletes. The study included 40 male alpine skiers aged 16-22 years residing in Bitlis, Türkiye, with 20 participants in the experimental group and 20 in the control group. Throughout the study, all participants continued similar regular alpine skiing training programs to control for potential differences in training volume and fitness levels. Considering the competition schedule, the intervention period was designed to last 12 weeks. During this period, the experimental group performed high-intensity interval training twice per week in addition to their regular skiing training, while the control group continued their regular training program. Exercise intensity during HIIT sessions was maintained at 85-95% of the athletes' maximum heart rate. Cardiorespiratory performance was evaluated using a maximal exercise test to assess maximal oxygen uptake (VO₂max), respiratory quotient (RQ), maximum heart rate (HRmax), and oxygen uptake per heartbeat (VO₂/HR). Anaerobic performance was assessed using the Wingate anaerobic power test, including peak power, average power, minimum power, power drop, and total energy output. The Shapiro-Wilk test was used to assess data normality. Paired-samples t-tests were used for within-group pretest-posttest comparisons, while independent-samples t-tests were used for between-group comparisons. The statistical significance level was set at p \< 0.05. The study was designed to evaluate the potential contribution of a 12-week HIIT program to anaerobic performance and cardiorespiratory adaptations in alpine skiing athletes. Keywords: Alpine skiing, high-intensity interval training, anaerobic power, VO₂max.

Acute Effects of Different Warm-Up Protocols in Amateur Basketball Players

Brief Summary This randomized controlled trial will compare the immediate effects of three warm-up protocols on physical performance in male amateur basketball players. A total of 45 licensed basketball players aged 15 to 25 years will be randomly assigned to one of three groups: standard dynamic warm-up, dynamic warm-up followed by classical hold-relax proprioceptive neuromuscular facilitation (PNF) stretching, or dynamic warm-up followed by short-duration self-administered PNF stretching. The main outcome will be the change in countermovement jump height. Additional outcomes will include flexibility, knee range of motion, squat jump height, 20-meter sprint time, agility, dynamic balance, and perceived exertion. Measurements will be performed before the assigned warm-up protocol, immediately after the protocol, and 15 minutes after the protocol. The study aims to determine whether short-duration self-PNF stretching can improve flexibility while preserving performance more effectively than classical PNF stretching. Each participant will complete the assigned protocol and all assessments during a single study session.

Audiovisual Conditions During Eight Weeks of BOSU Training in Taekwondo Athletes

This nonrandomized three-group study described changes in taekwondo-specific electronic impact scores, selective attention and repeated-sprint performance over eight weeks of supplementary BOSU ball balance and proprioception training delivered under three different audiovisual conditions. Athletes were recruited from three taekwondo clubs in Malatya, Turkiye, and each club trained under one condition: high-tempo music (140-160 beats per minute) combined with projected elite competition footage (MV), low-tempo music alone (110-130 beats per minute; LTM), or no music and no video (CON). All three groups completed the same BOSU programme, three sessions per week for eight weeks (24 planned sessions of 40-45 minutes), in addition to their usual taekwondo training. Assessments were conducted at week 1, week 4 and week 8. Because allocation was not randomized and each condition was delivered predominantly within one club, audiovisual condition is confounded with club and the analyses are exploratory and descriptive rather than causal.

Warm-Up Music Tempo and Time-of-Day Effects on Anaerobic Performance in Young Female Volleyball Players

This study examined whether listening to music of different tempo during warm-up is associated with differences in acute jump performance, perceived exertion and handgrip strength in young female volleyball players, and whether these responses differ between morning and evening testing. Thirteen healthy female volleyball players aged 10 to 14 years completed eight sessions. Each player performed a standardized 10-minute warm-up under four conditions: no music, music labelled 60 to 80 beats per minute, music labelled 90 to 110 beats per minute, and music labelled 120 to 140 beats per minute. Each condition was tested once in the morning (08:00-10:00) and once in the evening (18:00-20:00). The primary outcome was countermovement jump height. Secondary outcomes were jump-derived peak power, relative peak power, single-hand handgrip strength and rating of perceived exertion. Chronotype, subjective wellness, sleep quality and mood were assessed at baseline. Allocation was not randomized and the order of conditions was not documented at participant level, so the comparisons are descriptive and exploratory rather than causal.

Caffeine and Wrestling Performance in Male Wrestlers of Different Weight Classes: A Randomized Crossover Trial

Caffeine is commonly used by athletes to improve performance, but not everyone responds to it in the same way. In weight-class sports like wrestling, athletes are grouped by body weight. When caffeine is dosed based on body weight (4 mg per kg), heavier athletes receive a larger total amount of caffeine than lighter athletes. This study asked whether the effects of caffeine on wrestling performance and side effects differ across wrestling weight classes. Ninety-five male wrestlers (30 lightweight, 36 middleweight, and 29 heavyweight) completed two testing sessions: one after taking caffeine (4 mg/kg) and one after taking a placebo (an inactive capsule). Neither the wrestlers nor the researchers knew which capsule was given in each session. Each session included a countermovement jump test and a wrestling-specific fitness test that involved throwing a wrestling dummy. Heart rate, perceived exertion, and self-reported symptoms were also recorded. The study found that lightweight and middleweight wrestlers generally performed better after caffeine, while heavyweight wrestlers showed no performance improvement and reported more side effects, such as anxiety, rapid heartbeat, stomach discomfort, and insomnia. These differences occurred even though all wrestlers received the same caffeine dose relative to their body weight. The results suggest that a standard body-weight-based caffeine dose may not work equally well for all wrestlers. Lighter wrestlers may benefit more, while heavier wrestlers may experience more side effects without performance gains. These findings support the need for individualized caffeine dosing strategies in wrestling and similar weight-class sports. However, because body weight, total caffeine dose, and other weight-class-related factors were not separated in this study, the results should be considered exploratory and do not establish weight-specific recommendations.

Effects of FIFA 11+ Warm-Up Program on Motor Performance in Young Soccer Players

The purpose of this study was to investigate the effects of an 8-week FIFA 11+ warm-up program on selected motor performance parameters in young male soccer players aged 17-18 years. Participants were randomly assigned to either the experimental group (FIFA 11+ program) or the control group (traditional warm-up program). Key motor performance outcomes including sprint performance (10m and 20m), vertical jump (countermovement jump), flexibility (sit-and-reach), static balance (flamingo balance), agility (505 agility), and upper-body explosive power (backward medicine ball throw) were evaluated before and after the 8-week intervention.

Neuroscience-Based Exercise Training in Female Volleyball Players

24 volunteer professional female volleyball players (aged 16-21), licensed in the Turkish Volleyball Federation (TVF) Women's Volleyball League 2 and 3, will be included in the study. Participants will be randomized into intervention (n=12) and control (n=12) groups using www.randomizer.org. The intervention group will receive an 8-week (3 days/week) neuro-athletic exercise training program, including eye warm-up exercises and volleyball-specific visual and motor coordination stations, in addition to their regular training. The control group will continue with regular training only. Both groups will have equal total training time. Visual attention and decision-making strategies will be measured with a wearable eye-tracking system (Pupil Labs Invisible) during a serve task. Cortical activation (oxygenated and deoxygenated hemoglobin levels) in the frontal cortex during the same serve task will be measured simultaneously with functional near-infrared spectroscopy (fNIRS). Sport-specific physical fitness will be evaluated with the T-Agility Test, radar gun serve speed measurement, VERT wearable jump analysis system, Y-Balance Test, and sit-and-reach test. All assessments will be conducted before training begins and after the 8-week program. The study aims to determine whether neuro-athletic exercise training improves cortical activation, visual attention, decision-making processes, and sport-specific physical fitness parameters in professional female volleyball players, compared to a control group receiving regular training only.

Effects of Magnesium L-Threonate on Sleep, Recovery, and Athletic Performance in Collegiate Athletes

This study is testing whether a special form of magnesium called magnesium L-threonate can help improve sleep quality, recovery, and physical performance in college athletes. Magnesium is important for muscle recovery and sleep, but many forms of it do not enter the brain well. Magnesium L-threonate is unique in that it can cross the blood-brain barrier and may improve deep and REM sleep, heart rate variability, and brain recovery. In this study, healthy UCLA varsity athletes aged 18 to 35 will be randomly assigned to take either magnesium L-threonate or a placebo each evening for 4 weeks. They will wear a WHOOP strap to track sleep, recovery, and heart rate data. Performance tests including jump height, grip strength, and reaction time will be completed before and after the 4-week period. This study will help researchers determine if this supplement can support recovery and training in athletes and whether wearable technology can help monitor these changes in real time.

Neuromuscular Adaptations Following Eight Weeks of French Contrast Training in Elite Youth Football Players: Implications for Athlete Health and Performance

This randomized controlled trial aimed to investigate the effects of an 8-week French Contrast Training (FCT) intervention on reactive strength index (RSI), sprint performance, and anaerobic profile in elite youth football players

Cluster Training With Blood Flow Restriction in Competitive 200-m Freestyle Swimmers

This study evaluated the effects of adding individualized blood flow restriction (BFR) to cluster resistance training on swimming performance, physical fitness, and selected circulating growth factors in competitive swimmers. Forty competitive swimmers participated in a matched, non-randomized controlled intervention involving two groups (20 participants per group). The experimental group performed cluster resistance training combined with individualized BFR, whereas the control group completed the same training program without BFR. The intervention lasted 10 weeks, comprising five supervised training sessions per week (50 sessions in total). Each 100-minute session included a 15-minute warm-up, 30 minutes of dry-land cluster resistance training, 50 minutes of swimming-specific training, and a 5-minute cool-down. Dry-land resistance exercises were performed at 60-70% of one-repetition maximum (1RM). BFR pressure was individualized to 50% of arterial occlusion pressure (AOP) for the upper limbs and 60% for the lower limbs. Swimming training intensity was prescribed according to individual maximal heart rate (HRmax). The primary outcome was the change in 200-m freestyle swimming performance time from baseline to the end of the 10-week intervention. Secondary outcomes included standing long jump performance, mean 50-m split time during a continuous maximal 150-m swim, cadence-controlled Burpee repetitions, and resting serum concentrations of fibroblast growth factor-2 (FGF-2) and vascular endothelial growth factor A (VEGF-A). The study investigated whether individualized BFR combined with cluster resistance training was associated with greater improvements in swimming performance and physiological responses compared with cluster resistance training alone.

UCLA Magnesium Formulation Athlete Study

This randomized, double-blind, placebo-controlled trial will compare magnesium glycinate, magnesium L-threonate, and placebo in UCLA varsity athletes. Participants will complete a baseline monitoring period followed by 4 weeks of blinded nightly supplementation. WHOOP 4.0 data will be used to evaluate sleep efficiency, total sleep time, sleep consistency, heart rate variability, resting heart rate, and recovery metrics. Baseline and final testing will assess selected reaction and physical performance outcomes. The primary outcome is change in WHOOP-derived sleep efficiency from baseline week to final treatment week.

Neuro-Athletic Training on Goalkeeper Performance

This randomized controlled trial investigated the effects of an 8-week neuro-athletic training (NAT) program on dynamic balance, explosive strength, grip strength, and agility in elite soccer goalkeepers. Participants were randomly assigned to either an experimental group receiving NAT in addition to regular training or a control group continuing standard training. Pre- and post-intervention performance assessments were conducted to determine the effectiveness of the intervention.

Fermented Milk Drink With Lacticaseibacillus Paracasei Strain Shirota Helps Triathletes With Cold-Like Symptoms Before and After a Race

This study aims to evaluate whether a fermented milk drink containing the probiotic strain Lacticaseibacillus paracasei strain Shirota (LCS), commonly found in Yakult®, can help reduce upper respiratory symptoms in triathletes before and after competition. Athletes often experience cold-like symptoms due to physical stress, intense training, and immune system challenges. The study investigates whether daily consumption of this probiotic drink can help improve immune response and reduce the incidence or severity of symptoms such as sore throat, nasal congestion, or coughing. This is a randomized, double-blind, placebo-controlled, parallel-group study involving healthy adult triathletes. Participants will be randomly assigned to receive either the probiotic drink or a placebo for a specific period before and after a triathlon event. Symptoms and health markers will be tracked through questionnaires and biological samples. The goal is to explore whether probiotic supplementation can provide practical, non-pharmacological support for athletes' immune health and well-being during intense physical activity.

Delayed Morning Training, Sleep, and Change-of-Direction Performance in Badminton Athletes

This randomized controlled trial will investigate whether delaying the start of morning training from 7:00 AM to 9:00 AM improves nocturnal sleep and change-of-direction performance in elite badminton athletes. A total of 38 athletes with an established morning-training routine will be randomly assigned in a 1:1 ratio to either a usual morning-training group starting at 7:00 AM or a delayed morning-training group starting at 9:00 AM. Both groups will follow the same training content, duration, intensity, coaching arrangements, and recovery procedures for three weeks. Nocturnal sleep will be objectively monitored using wrist-worn activity monitors, with total sleep time as the primary outcome. Change-of-direction performance will be assessed using the modified 505 test. Additional outcomes will include sleep opportunity, sleep efficiency, sleep onset latency, nighttime awakenings, bedtime and wake time, nap duration, 24-hour total sleep, training load, and training adherence. The study aims to determine whether a later morning-training schedule can provide athletes with greater sleep opportunity without compromising training quality or physical performance.

Physiological and Performance Characteristics of HYROX Athletes

HYROX© is a fast-growing fitness competition that combines long-distance running with functional exercises such as sled pushes, rowing, and weightlifting movements. Although the sport has attracted more than a million participants worldwide, little scientific research has looked at the health, body composition, and physical fitness of the people who compete in it. This study will compare body composition, fitness, and performance between two groups of HYROX© participants: those competing at a recreational (amateur) level and those competing at an elite level. Adult volunteers (ages 18-65) who train for or compete in HYROX© will be invited to take part. Researchers will measure body composition using a whole-body scan (DXA), skinfold thickness, and muscle ultrasound; resting metabolism; daily physical activity (using a wearable activity tracker); muscle strength and jumping ability; aerobic fitness (a treadmill running test); and short-burst power (a cycling test). Participants will also complete questionnaires about their motivation to exercise, their diet, and their use of dietary supplements, and will wear a heart rate monitor and activity tracker during an official HYROX© competition. The results will help researchers, coaches, and athletes better understand how the bodies and training needs of HYROX© athletes differ by competitive level, which may support the development of safer and more effective training programs.

Effect of an 8-Week Core Exercise Program on Jumping and Balance in Recreational Soccer Players Aged 14-16 Years

This randomized controlled trial examines the effect of an 8-week core exercise program on jumping and balance performance in recreational male soccer players aged 14 to 16 years. Thirty-six players were randomly assigned to an experimental group or a control group (18 per group). The experimental group performed a structured core exercise program twice a week, in addition to regular soccer training. The control group continued regular soccer training only. Standing long jump, vertical jump (squat jump), and static balance (Flamingo Balance Test) were measured before and after the 8-week period.

Sideritis Supplementation and Performance

The purpose of this study is to examine the effect of sideritis consumption on physiological and performance indicators in adult subjects and compare it with the control trial.

Individualized Physical Conditioning Based on Heart Rate Variability and Workload Monitoring in Table Tennis Players

This study compares two 12-week conditioning programs in 48 competitive table tennis players. Players were randomly assigned to an experimental group or a control group. The experimental group followed an individualized conditioning program in which training intensity, volume, and content were adjusted weekly according to each athlete's morning heart-rate variability (HRV, 5-minute supine rMSSD) and acute:chronic workload ratio (ACWR) computed from session-RPE training load. On days when HRV fell more than one standard deviation below the athlete's rolling 7-day average, high-intensity components were replaced with low-intensity work. The control group followed a standardized conditioning program matched for session frequency (three integrated sessions per week for 12 weeks, no individualized monitoring feedback). The program progressed through eight phases (foundation, accumulation, deload, intensification, transition, taper I-II, peak/post-test). Both groups were assessed before and after the intervention on 24 measures of neuromuscular performance (jump height, reactive strength index, rate of force development, force asymmetry, EMG onset latency and peak amplitude), sensorimotor performance (simple and saccadic reaction time, movement time, balance), cardiorespiratory fitness (VO2max, heart-rate recovery, blood lactate), and competitive match performance (win rate, stroke accuracy, placement accuracy, rally efficiency, ball speed, national ranking points). The primary outcome is simple reaction time. The study tests whether readiness-guided individualization improves performance more than standardized conditioning. The study protocol, dataset, and analysis code are openly available in the Zenodo repository (DOI: 10.5281/zenodo.21343993).

Weighted-Vest Versus Bodyweight Plyometric Training in Youth Female Soccer Players

Lower extremity strength, explosive power, dynamic balance and functional movement quality are important determinants of performance and injury prevention in soccer. This study compares the effects of bodyweight plyometric training and weighted-vest plyometric training on athletic performance in young female soccer players. Participants are randomly assigned to three groups: Bodyweight Plyometric Training (BW-PT), Weighted-Vest Plyometric Training (EL-PT; vest equal to 10% of body weight) and Control (CG; routine soccer training only). The interventions are performed twice a week for 6 weeks. Isokinetic knee extensor and flexor strength (60°/s and 120°/s), jumping performance (standing long jump, countermovement jump height and 15-second repeated jump test), functional movement (Functional Movement Screen) and dynamic balance (Y-Balance Test) are assessed before and immediately after the training period. The originally planned 4-week detraining follow-up was cancelled before data analysis because it could not be completed within the funding period of the project.

Transcranial Direct Current Stimulation Promotes Punching and Movement Speed in Elite Male Boxers

This study investigates whether transcranial direct current stimulation (tDCS), a safe and non-invasive brain stimulation technique, can improve punching and movement speed in elite male boxers. Twenty-four elite male boxers will receive 2 mA tDCS over either the primary motor cortex (M1), the dorsolateral prefrontal cortex (DLPFC), or sham stimulation for 20 minutes, in a randomized, counterbalanced order. Punching speed and movement speed will be assessed before and at three time points after stimulation (immediately, 20 minutes, and 45 minutes). The study aims to determine whether tDCS can enhance boxing-specific performance and whether the effects differ between stimulation sites.

HIIT Versus High-Volume Training in Competitive Para Swimmers

This study compared the effects of four weeks of reduced-volume high-intensity interval training and higher-volume moderate-intensity swimming training on repeated-sprint ability, physiological responses, and body composition in competitive para swimmers. Twenty-four national-level swimmers representing World Para Swimming sport classes S5-S10 and S14 were randomly allocated to one of the two training interventions by drawing sealed group assignments. Both groups completed two supervised sessions per week for four weeks. Repeated-sprint ability was assessed before and after the intervention using eight maximal 15-m freestyle sprints.

Core Stability Training and Breaststroke Performance in University Students Learning to Swim

The purpose of this study was to find out whether adding core stability exercises to regular swimming lessons could improve breaststroke performance in university students learning to swim. These exercises involve holding the body in set positions to train muscles that help maintain posture and stability. The study included 136 university students aged 18 to 20 years. Participants were assigned by chance to one of two groups. Both groups attended the same 90-minute breaststroke lesson each week. After each lesson, one group completed 30 minutes of core stability exercises, while the other group completed 30 minutes of low-intensity stretching and relaxation activities. These additional sessions took place once a week for 14 weeks. The main comparison was the time needed to swim 25 meters using breaststroke after the training period. Other assessments measured kicking performance, the number of swimming strokes, distance traveled per stroke, and muscle endurance during exercises performed on land.