Physiologic performance test differences in female volleyball athletes by competition level and player position

Differences in external load among indoor and beach volleyball players during elite matches

The aim of this cross-sectional study was to examine relationships of external load variables between beach and indoor volleyball amongst individual positions on the team. The movements of eight beach and fourteen indoor female volleyball players were recorded during elite playoff matches; in total, 2,336 three-dimensional trajectories were analyzed. Time-outs and intervals between rallies or sets were excluded from active play time. In both beach and indoor volleyball, 80% of rallies lasted up to 10 s, and players covered 4.5 to 10 m of court during 60% of rally play. Differences in dependent variables of external load were found between independent variables of sports and player positions (p < 0.05). The distance covered in beach volleyball rallies and Player Load™ parameters was significantly higher by up to 23%. The unstable court surface with sand in beach volleyball elevated explosive Player Load™ (accelerations in all three orthogonal planes of motion higher than 3.5 m/s3) in beach volleyball players compared to those of players on stable flooring in indoor. While beach volleyball blocker and defender positions showed no significant difference in parameters between each other, they differed in all parameters when compared to player positions in indoor volleyball. Indoor blocker and libero reached higher loads than setter, outside and opposite positions in various parameters. Factors that influence external load include the larger relative court areas covered by each player in beach volleyball, complexity of players' roles, and game strategy. This data adds to the knowledge of elite match demands in female volleyball. Specified agility-drill distances and times are essential for training optimization and must be supported by scientific observation. Researchers, coaches, and conditioning specialists should find this helpful for achieving a higher degree of training regulation.

Assessing the Maximal Mechanical Capacities Through the Load-Velocity Relationship in Elite Versus Junior Male Volleyball Players

BACKGROUND

Physical testing is crucial for athlete monitoring, talent identification, optimizing training, and tailoring programs to enhance game-performance in elite competitions.

HYPOTHESIS

Load-velocity (L-V) relationship variables discriminate between elite and junior volleyball players, correlate with volleyball-specific performance, and are generalizable across lower- and upper-body exercises.

STUDY DESIGN

Cross-sectional study.

LEVEL OF EVIDENCE

Level 3.

METHODS

A total of 9 elite and 11 junior volleyball players were assessed for the L-V relationship (load-axis intercept [L0], velocity-axis intercept [v0], and area under the L-V relationship line [Aline]) during the countermovement jump (CMJ) and bench press throw (BPT) exercises. Block and spike jump height, as well as standing and jumping spike speed were assessed 24 hours later.

RESULTS

Elite players presented greater magnitude in the L-V variables (P ≤ 0.03; effect size [ES] ≥ 1.06) and higher volleyball-specific performance (P ≤ 0.03; ES ≥ 1.09) than juniors (except for CMJ v0 and Aline). The L-V relationship variables were significantly associated with the block and spike jump height and jumping spike speed only in elite players (r ≥ 0.703 and P ≤ 0.04 in 11 out of 18 correlations). No significant associations were observed between CMJ and BPT for any L-V relationship variable (r ≤ 581; P ≥ 0.08, except for Aline in junior players).

CONCLUSION

The L-V relationship is a practical procedure to assess volleyball players' maximal mechanical capacities, which are associated with volleyball-specific performance in elite players. However, these data should not be used interchangeably between playing standards or exercises.

CLINICAL RELEVANCE

This information might help strength and conditioning coaches to prescribe more effective training programs that focus on developing the specific physical capacities necessary for players to potentially advance to elite status.

Examining Countermovement Jump Strategies Between Women's NCAA Division I Sports

ABSTRACT

Donahue, PT, Peel, SA, Rush, M, McInnis, AK, Littlefield, T, Calci, C, and Brutofsky, T. Examining countermovement jump strategies between women's NCAA Division I sports. J Strength Cond Res 37(10): 2052-2057, 2023-The purpose of this study was to examine countermovement vertical jump performance among female athletes who rely heavily on vertical jump performance within their given sport. Forty-five female athletes representing 3 teams (basketball, volleyball, and beach volleyball) competing at the NCAA Division I level completed 2 maximal effort countermovement jumps (CMJ) using a portable force platform. A 1-way analysis of variance was used to compare groups across each variable. Statistically significant differences were found between the groups regarding propulsive duration and time to takeoff with basketball showing the shortest time and beach volleyball having the longest times ( p < 0.05). In addition, differences were seen in countermovement depth and mean propulsive force between the groups with basketball displaying the smallest countermovement and highest force ( p < 0.05). No differences were seen in jump height and reactive strength index modified. Greater force and shorter durations in basketball athletes versus the low force and long durations in the beach volleyball athletes suggest that sporting backgrounds play a large role in how the CMJ is performed. This information can aid strength and conditioning practitioners in the design of training programs that are sport specific to the strategies used by the athlete.

Athleticism and sex impact neural processing of sound

Biology and experience both influence the auditory brain. Sex is one biological factor with pervasive effects on auditory processing. Females process sounds faster and more robustly than males. These differences are linked to hormone differences between the sexes. Athleticism is an experiential factor known to reduce ongoing neural noise, but whether it influences how sounds are processed by the brain is unknown. Furthermore, it is unknown whether sports participation influences auditory processing differently in males and females, given the well-documented sex differences in auditory processing seen in the general population. We hypothesized that athleticism enhances auditory processing and that these enhancements are greater in females. To test these hypotheses, we measured auditory processing in collegiate Division I male and female student-athletes and their non-athlete peers (total n = 1012) using the frequency-following response (FFR). The FFR is a neurophysiological response to sound that reflects the processing of discrete sound features. We measured across-trial consistency of the response in addition to fundamental frequency (F0) and harmonic encoding. We found that athletes had enhanced encoding of the harmonics, which was greatest in the female athletes, and that athletes had more consistent responses than non-athletes. In contrast, F0 encoding was reduced in athletes. The harmonic-encoding advantage in female athletes aligns with previous work linking harmonic encoding strength to female hormone levels and studies showing estrogen as mediating athlete sex differences in other sensory domains. Lastly, persistent deficits in auditory processing from previous concussive and repetitive subconcussive head trauma may underlie the reduced F0 encoding in athletes, as poor F0 encoding is a hallmark of concussion injury.

The Role of Age, Sex, Body Mass Index, and Sport Type on the Dynamic Exertion Test in Healthy Athletes: A Cross-Sectional Study

BACKGROUND

The dynamic exertion test (EXiT) was developed to help inform return to play after sport-related concussion, but some factors may threaten the internal validity of EXiT and affect clinical interpretation.

OBJECTIVE

To compare age, sex, BMI, and sport types across EXiT physiological [pre-EXiT and post-EXiT percentage of maximum heart rate (HR %max) and blood pressure (BP)], performance (change-of-direction task completion time and committed errors), and clinical [symptoms and rating of perceived exertion (RPE)] outcomes among healthy adolescents and adults.

STUDY DESIGN

Cross-sectional.

METHODS

Eighty-seven participants ( F = 55, 37.4%) reported symptoms and RPE during the EXiT, which consists of a 12-minute treadmill running protocol, and the dynamic circuit, ball toss, box shuffle (SHUF) and carioca (CAR), zig zag (ZZ), proagility (PA), and arrow agility (AA) tasks. Independent samples t tests were conducted for pre-EXiT and post-EXiT HR %max and BP and change-of-direction task completion time and Mann-Whitney U tests for errors, symptoms, and RPE. A series of 1-way analysis of variance (ANOVAs) and Kruskal-Wallis H tests were conducted to compare collision, contact, and noncontact sport types.

RESULTS

Adolescents had lower completion time across AA ( P = 0.01) and male athletes lower than female athletes on CAR, ZZ, PA, and AA ( P < 0.04). Male athletes reported greater RPE after the SHUF, CAR, and AA ( P < 0.03). HR %max , errors, and symptoms were equivocal across all subgroups ( P > 0.05).

CONCLUSION

Age and sex should be considered in the interpretation of performance and clinical, but not physiological, EXiT outcomes. The EXiT is a standardized exercise assessment and generalizable to healthy athletes.

Correlations Between Preseason Functional Test Scores and Game Performance in Female Collegiate Volleyball Players

Background

Functional tests (FT) are assessment tools that attempt to evaluate balance, flexibility, strength, power, speed, or agility through performance of gross motor skills. FT are frequently administered by coaches or sports medicine professionals to evaluate athletic ability, to predict performance, to identify athletes at risk for injury, or to evaluate an athlete's ability to return to sport after injury. Functional tests which can provide accurate or predictive information regarding athletic ability would be advantageous to coaching staffs or medical professionals.

Purpose

The primary purpose of this study was to identify correlations between preseason FT scores and in-season game statistics in a cohort of female collegiate level volleyball (VB) players. A secondary purpose was to present FT descriptive data for this cohort based on level of competition, player position, and starter status.

Study Design

prospective cohort; correlational.

Methods

One hundred and thirty-one female collegiate VB players representing three levels of competition completed four FT [standing long jump (SLJ), single-leg hop (SLH), lower extremity functional test (LEFT), and the Y-Balance Test - Lower Quarter (YBT-LQ)] at the start of the preseason. Player statistics were collected from team records at the completion of the season.

Results

Starters performed significantly better on all tests. There were moderate negative correlations between LEFT scores and game statistics for liberos, defensive specialists, and outside hitters. There were moderate positive correlations between YBT-LQ composite scores and game statistics for liberos, defensive specialists, hitters, and middle blockers. There were also low to moderate level positive correlations between SLJ and SLH scores and game performance for outside hitters. There were low to moderate level positive correlations between SLH scores and game performance for middle blockers and opposite side hitters.

Conclusions

The results of this study indicate that there are low to moderate correlations between some preseason functional test scores and some game statistics. The SLJ, SLH, LEFT, and YBT-LQ tests may help coaches with talent identification and/or may influence training strategies.

Level of Evidence

3.

Effects of Maximal and Submaximal Anaerobic and Aerobic Running on Subsequent Change-of-Direction Speed Performance among Police Students

Simple Summary

Change-of-direction maneuvers are frequently performed by police officers and athletes. These maneuvers are typically performed with the intention of being maximally fast. Often, an officer or an athlete will run at a certain pace before commencing a change-of-direction speed maneuver. Depending on the duration and intensity of this running activity, their performance of the change-of-direction speed maneuver may be reduced. This study determined the degree to which the preceding maximal and submaximal anaerobic and aerobic activity affect the subsequent performance of the change-of-direction speed maneuver. We found that both anaerobic and aerobic running activities decreased the speed of the subsequent performance on the Illinois Agility Test. We also found that anaerobic running at 85% and 90% had a greater impact on change-of-direction speed performance than did aerobic running at these intensities. Above 90% intensity, anaerobic and aerobic performance similarly impacted the change-of-direction speed. As such, given the requirement for tactical personnel and intermittent, multidirectional sports athletes to perform a change-of-direction speed maneuver following a period of submaximal anaerobic or aerobic activity, increasing fitness may be a means of reducing the negative impacts of preceding submaximal impacts on change-of-direction speed performance.

Abstract

Change-of-direction speed (CODS) directly impacts success in sports, police, and military performance. Movements requiring CODS are often preceded by aerobic or anaerobic running. Therefore, this study investigated the effects of maximal and submaximal anaerobic and aerobic running on subsequent CODS performance. A sample of 50 police students (42% female and 58% male) performed a maximal 300-yard shuttle run test (SR300y) and a 2.4-km Cooper test (CT2.4km) at maximal effort and also at 95, 90, 85, 80, and 75% of maximal effort. CODS was assessed using the Illinois Agility Test (IAT) immediately following each intensity level of each test at 12 separate testing sessions. To avoid fatigue, the period between each consecutive session was a minimum of 3 days. Paired samples t-tests were used to determine the differences between the two conditions (anaerobic lactic and aerobic) and for the IAT. A repeated measure analysis of variance with a Bonferroni post hoc test was used to analyze partial effects of different running intensities on the IAT. A significant reduction in speed was observed between the initial IATmax time and the IATmax time after performing the SR300y at intensities of 95, 90, 85, and 80% of maximal speed on this test. IAT performance was significantly slower when performed after the CT2.4km at 95 and 90% of maximal aerobic speed. The effects of the SR300y on the IAT were significantly greater than the effects of the CT2.4km. No significant differences were found by sex. Building up to 90% intensity, anaerobic running has a greater negative impact on subsequent CODS performance than does aerobic running.

Neurobiological tensegrity: The basis for understanding inter-individual variations in task performance?

Bernstein's (1996) levels of movement organization includes tonus, the muscular-contraction level that primes individual movement systems for (re)organizing coordination patterns. The hypothesis advanced is that the tonus architecture is a multi-fractal tensegrity system, deeply reliant on haptic perception for regulating movement of an individual actor in a specific environment. Further arguments have been proposed that the tensegrity-haptic system is implied in all neurobiological perception and -action. In this position statement we consider whether the musculoskeletal system can be conceptualized as a neurobiological tensegrity system, supporting each individual in co-adapting to many varied contexts of dynamic performance. Evidence for this position, revealed in investigations of judgments of object properties, perceived during manual hefting, is based on each participant's tensegrity. The implication is that the background organizational state of every individual is unique, given that no neurobiological architecture (musculo-skeletal components) is identical. The unique tensegrity of every organism is intimately related to individual differences, channeling individualized adaptations to constraints (task, environment, organismic), which change over different timescales. This neurobiological property assists transitions from one stable state of coordination to another which is needed in skill adaptation during performance. We conclude by discussing how tensegrity changes over time according to skill acquisition and learning.

Anthropometric Characteristics and Vertical Jump Abilities by Player Position and Performance Level of Junior Female Volleyball Players

Although absolute jump heights should be considered an important factor in judging the performance requirements of volleyball players, limited data is available on age-appropriate categories. The purpose of this study is to determine the differences in specific anthropometric characteristics and jumping performance variables in under-19 female volleyball players in relation to playing position and performance level. The sample of subjects consisted of 354 players who prepared for the U19 Women's Volleyball European Championship 2020 (17.4 ± 0.8 years, 1.81 ± 0.07 m, 67.5 ± 7.1 kg). Playing positions analyzed were setters (n = 55), opposites (n = 37), middle blockers (n = 82), outside hitters (n = 137), and liberos (n = 43). The results showed player position differences in every performance level group in variables of body height, spike, and block jump. Observed differences are a consequence of highly specific tasks of different positions in the composition of the team. Players of different performance levels are significantly different, with athletes of higher-ranked teams achieving better results. The acquired data could be useful for the selection and profiling of young volleyball players.

Agility training in volleyball: a systematic review

BACKGROUND

Volleyball is an intermittent, extremely dynamic and open-skill team sport in which players perform a variety of acyclic movements while constantly changing game situation. The purpose of this systematic review was to provide a summary of the research that has examined intervention strategies to improve agility performance in volleyball and to synthesise the tests used to evaluate agility in volleyball.

METHODS

A systematic review was performed in PubMed, Scopus, Web of Science and Google Scholar with titles, abstracts, and full texts that were analysed according to predefined inclusion criteria to find relevant studies. Moreover, the methodological quality of the studies selected was assessed.

RESULTS

Twelve studies (n = 348 participants) were included. The selected studies had a methodological quality rated poor-to-moderate (average score of 3.9, range: 1 to 6). Results showed that of all the training interventions, plyometric-based training present the greatest improvement in agility (average of 7.7%). Moreover, the agility T-test was the most used test.

CONCLUSIONS

In light of the poor-to-moderate methodological quality, there is a need for developing specific longitudinal and controlled studies with the aim of studying the effect of diversified training interventions on the development of agility in volleyball players.

Positional Body Composition of Female Division I Collegiate Volleyball Players

Bisch, KL, Bosch, TA, Carbuhn, A, Stanforth, PR, Oliver, JM, Bach, CW, and Dengel, DR. Positional body composition of female division I collegiate volleyball players. J Strength Cond Res 34(11): 3055-3061, 2020-The primary study objective was to measure positional differences in total and regional body composition among female NCAA Division I collegiate volleyball players using dual X-ray absorptiometry (DXA). The secondary objective was to examine normative age curves for fat and lean mass (LM) variables. Ninety female volleyball players from 5 universities received a DXA scan. Athletes were categorized by position: middle blocker (MB = 31), outside hitter (OH = 32), setter (ST = 9), and Libero (LB = 18). Height, body mass, total and regional fat mass (FM), LM, bone mineral density (BMD), and abdominal visceral adipose tissue were measured by DXA. Body mass distribution ratios were calculated. The secondary age analysis included a subset of 153 DXA scans (n = 83, ages 18-21 years). Front row players (i.e., MB and OH) had significantly greater total and regional LM and BMD measures (p < 0.05, all), compared with non-front row players (i.e., LB and ST). Differences in total LM (p < 0.001) were significantly influenced by height. Front row players had consistently lower mass distribution ratios compared with non-front row players (p < 0.05, all). Lean mass index (LMI, p = 0.752) and FM index (FMI, p = 0.392) were not significantly different across ages. Back row players have greater relative upper body mass, whereas mass in front row players is more evenly distributed between the upper and lower body. Bone mineral density differences may be influenced by repeated impact of jumping during the attacking and blocking actions of front row players. Minimal changes in LMI and fluctuations in FMI can be expected across an athlete's career.

A Retrospective Analysis of the National Youth Teams in Volleyball: Were They Always Faster, Taller, and Stronger?

Mireille, M, Johan, P, Matthieu, L, and Pieter, V. A retrospective analysis of the national youth teams in volleyball: Were they always faster, taller, and stronger? J Strength Cond Res XX(X): 000-000, 2020-Although there are numerous studies comparing the characteristics of young and adult volleyball players of different levels, it remains unclear to what extent these findings can be used for performance prediction because very few are based on longitudinal or retrospective analyses. The aim of the current retrospective study was to test to what extent anthropometry, physical performance, and motor coordination can predict future selection in national youth teams. From 2012 to 2015, 1738 10- to 13-year-old boys and girls who played volleyball completed 3 anthropometric, 4 physical performance, and 3 motor coordination tests. In January 2020, 52 athletes of this sample were found to be part of one of the national youth teams of Belgium. A multivariate analysis of covariance, discriminant analyses, and logistic regression analyses were conducted to compare the test results of the selected vs. the nonselected players. Significance level was set at p ≤ 0.05. Results showed that the selected players were already taller and showed better jumping performance, and for females, they tended to have better motor coordination at the time of baseline measurement. Therefore, it seems important to focus on the development of motor coordination and jumping performance at young ages because superiority in these characteristics increases the chances to be selected for the national team 4-8 years later. Nevertheless, considering the large variation in results, selection cannot be made based on these characteristics alone. The practical implications for coaches and federations with respect to training and talent detection are discussed.

The Relationship Between Physical Fitness Qualities and Sport-Specific Technical Skills in Female, Team-Based Ball Players: A Systematic Review

Background

Understanding the relationships between physical fitness attributes and sport-specific technical skills may assist with the establishment of beneficial training interventions. The aim of this systematic review was to determine if physical fitness qualities were associated with performance of sport-specific technical skills in female, team-based ball players.

Methods

Five databases (MEDLINE, EMBASE, SPORTDiscus, ProQuest, and Scopus) were searched for relevant studies up to April 15, 2019. Full-text articles investigating relationships between physical fitness and sport-specific technical skills in female, team-based ball players were included. Methodological quality of included studies was appraised using a modified Downs and Black checklist. Data synthesis was conducted to determine the summary of evidence based on the number of significantly associated relationships divided by the total relationships assessed. An individual relationship was defined as a reported result examining the association between a single physical fitness variable and a single sport-specific technical skill.

Results

Data synthesis of grouped female ball players from 41 included studies revealed three clear associations: (i) body composition and defensive technical skills (19/29; 66%), (ii) agility and movement with a ball (4/6; 67%), and (iii) coordination and movement with a ball (3/5; 60%). An uncertain association exists between cardiorespiratory fitness and defensive technical skills (2/5; 40%). No association or an unknown conclusion (< 5 relationships reported) exists between all remaining physical fitness attributes and sport-specific technical skills. Sub-analyses revealed clear associations between body composition and throwing/shooting (using hands) in junior ball players (15/15; 100%) and with movement with a ball in elite (6/9; 67%) and senior (6/6; 100%) ball players. Three uncertain associations were found between offensive technical skills and agility in elite ball players (3/8; 38%), and with speed in elite (6/14; 43%) and junior (7/18; 39%) female ball players.

Conclusion

There is limited evidence available to demonstrate relationships between physical fitness qualities and sport-specific technical skills in female, team-based ball players. This lack of association is possibly due to reductionist methods in available literature and a lack of research in female ball players globally.

Registration

CRD42017065339 (PROSPERO on 12 May 2017).

COMPARISON of LOWER QUARTER Y-BALANCE TEST SCORES for FEMALE COLLEGIATE VOLLEYBALL PLAYERS BASED on COMPETITION LEVEL, POSITION, and STARTER STATUS

BACKGROUND

The Lower Quarter Y-Balance Test (YBT-LQ) is used by sports medicine professionals to measure an athlete's dynamic balance. The YBT-LQ is used by clinicians to track recovery during clinical rehabilitation, assess an athlete's readiness to return to sport after injury, and to identify athletes potentially at-risk for a time-loss injury. Normative data for the YBT-LQ are lacking for female collegiate volleyball (VB) players. The purpose of this study was to examine preseason YBT-LQ scores and their relationships to level of competition, starter status, player position, and prior lower quadrant (i.e., low back and lower extremities) injury history.

METHODS

One-hundred thirty-four female collegiate VB players (mean age = 19.3 ± 1.1 years) representing athletes from three levels of competition (D II = 32, D III = 77, NAIA = 25) participated in this study. Athletes reported their prior injury history and performed the YBT-LQ testing protocol.

RESULTS

NAIA and D III athletes demonstrated significantly greater reach measures on the YBT-LQ than D II athletes in several directions. Starters demonstrated significantly greater reach measures in five out of eight reach directions. Liberos/defensive specialists/setters demonstrated significantly greater posterolateral and composite reach measures bilaterally. There was no difference in reach measures based on prior history of lower quadrant (low back and lower extremities) injury.

CONCLUSION

This study provides normative data for YBT-LQ in female collegiate volleyball players. The data presented in this report may be used by coaches and rehabilitation professionals when evaluating dynamic balance in healthy volleyball players and by clinicians to compare an injured athlete's recovery to norms.

LEVEL OF EVIDENCE

3b.

The effects of sole vibration stimulation on Korean male professional volleyball players' jumping and balance ability

[Purpose] The purpose of this study was to investigate differences in jumping ability and lower limb balance ability elicited by plyometric training and vibration exercise, of volleyball players with and without ankle injuries, which frequently occur among Korean professional volleyball players. [Subjects and Methods] Twenty-eight volleyball players were divided into the following groups: plyometric with ankle injury (PAI) group; plyometric with non-ankle injury (PAN) group; vibrator with ankle injury (VAI) group; and vibrator with non-ankle injury (VAN) group. After exercise and whole body vibration stimulation, their vertical jumping abilities, side step, and static equilibrium ability were measured. [Results] The vibration exercise group which had experienced ankle injuries showed significant improvements in the sidestep test after the intervention compared to before the intervention. In vertical jumping as well, significant improvements were observed in the VAI group and the VAN group following vibration exercise. In the balance ability test, significant improvesments in the PAN group and the PAI group were observed after the intervention. According to the results of the right side, there was significant change in the left/back side test and the right/back side test before and after the intervention; and in the test of one-leg standing with eyes closed, there were significant group, timing, and interaction effects. [Conclusions] The training method which effectively improved the jumping ability of volleyball players was plyometric training, and for balance ability improvement, whole body vibration exercise was effective.

Stature and jumping height are required in female volleyball, but motor coordination is a key factor for future elite success

It was hypothesized that differences in anthropometry, physical performance, and motor coordination would be found between Belgian elite and sub-elite level female volleyball players using a retrospective analysis of test results gathered over a 5-year period. The test sample in this study consisted of 21 young female volleyball players (15.3 ± 1.5 years) who were selected to train at the Flemish Top Sports Academy for Volleyball in 2008. All players (elite, n = 13; sub-elite, n = 8) were included in the same talent development program, and the elite-level athletes were of a high to very high performance levels according to European competition level in 2013. Five multivariate analyses of variance were used. There was no significant effect of playing level on measures of anthropometry (F = 0.455, p = 0.718, (Equation is included in full-text article.)= 0.07), flexibility (F = 1.861, p = 0.188, (Equation is included in full-text article.)= 0.19), strength (F = 1.218, p = 0.355, (Equation is included in full-text article.)= 0.32); and speed and agility (F = 1.176, p = 0.350, (Equation is included in full-text article.)= 0.18). Multivariate analyses of variance revealed significant multivariate effects between playing levels for motor coordination (F = 3.470, p = 0.036, (Equation is included in full-text article.)= 0.59). A Mann-Whitney U test and a sequential discriminant analysis confirmed these results. Previous research revealed that stature and jump height are prerequisites for talent identification in female volleyball. In addition, the results show that motor coordination is an important factor in determining inclusion into the elite level in female volleyball.

Enhancing physical performance in male volleyball players with a caffeine-containing energy drink

There are no scientific data about the effects of caffeine intake on volleyball performance. The aim of this study was to investigate the effect of a caffeine-containing energy drink to enhance physical performance in male volleyball players. A double-blind, placebo-controlled, randomized experimental design was used. In 2 different sessions separated by 1 wk, 15 college volleyball players ingested 3 mg of caffeine per kg of body mass in the form of an energy drink or the same drink without caffeine (placebo). After 60 min, participants performed volleyball-specific tests: standing spike test, maximal squat jump (SJ), maximal countermovement jump (CMJ), 15-s rebound jump test (15RJ), and agility T-test. Later, a simulated volleyball match was played and recorded. In comparison with the placebo drink, the ingestion of the caffeinated energy drink increased ball velocity in the spike test (73 ± 9 vs 75 ± 10 km/h, P < .05) and the mean jump height in SJ (31.1 ± 4.3 vs 32.7 ± 4.2 cm, P < .05), CMJ (35.9 ± 4.6 vs 37.7 ± 4.4 cm, P < .05), and 15RJ (29.0 ± 4.0 vs 30.5 ± 4.6 cm, P < .05). The time to complete the agility test was significantly reduced with the caffeinated energy drink (10.8 ± 0.7 vs 10.3 ± 0.4 s, P < .05). In addition, players performed successful volleyball actions more frequently (24.6% ± 14.3% vs 34.3% ± 16.5%, P < .05) with the ingestion of the caffeinated energy drink than with the placebo drink during the simulated game. A caffeine-containing energy drink, with a dose equivalent to 3 mg of caffeine per kg body mass, might be an effective ergogenic aid to improve physical performance and accuracy in male volleyball players.