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1.
Percept Mot Skills ; 130(6): 2603-2620, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37879103

RESUMO

Our primary objective in this study was to investigate the offensive strategies employed in the attack phase of men's volleyball, specifically focusing on side-out as stratified by the type of confrontation that was determined by the opponent's team performance. We analyzed 5524 attacking actions during 22 games of the 12 teams that participated in the Volleyball Men's Superliga (season 2021-2022). Based on their final rankings in the championship, we classified these teams into three tiers: high-performance, intermediate-performance, and low-performance. Subsequently, we examined the dynamics of these matches using Social Network Analysis. We found that the opponent teams' performance levels did not influence the game dynamics. Notably, the eigenvector values were prominently higher for Attack Zones 2 and 4, wherein the middle-blocker jumped to attack close to the setter across all networks. Thus, setters opted for traditional and low-risk strategies to minimize errors, disregarding available information about the skill level of the opposing team, making their offensive tactics predictable.


Assuntos
Desempenho Atlético , Voleibol , Masculino , Humanos
2.
Sci Rep ; 13(1): 5817, 2023 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-37037981

RESUMO

The purpose of this study was to use an inertial measurement unit (IMU) to analyze variations in the jump outcomes concerning weekly training days, and the dependencies between the number of jumps per minute and the jump height. An experimental research design was adopted across three weeks of the final play-off of a volleyball championship. Through an IMU, the external load of seven male elite volleyball athletes of a top rating team from Portuguese 1st Division (age: 30.5 ± 3.5 years; height: 200.2 ± 6.3 cm; body mass: 93.0 ± 8.1 kg; BMI: 23.1 ± 2.3 kg/m2) was monitored. Repeated measures ANOVA was executed to compare the outcomes between training days. It was observed a similar density of jumps during the week. However, when comparing MD-1 to MD-2, a more significant average number of jumps per minute was observed in MD-1 (1.3 ± 0.2 vs. 1.0 ± 0.2). Additionally, a positive, large and significant correlation was registered between the number of jumps and the height of the jump. Those results highlight the benefits of the specific training, leading to greater stimulation and improvement, in a game-like context, of the stretching-shortening cycle, observed in every jump action in volleyball.


Assuntos
Desempenho Atlético , Voleibol , Humanos , Masculino , Adulto , Voleibol/fisiologia , Movimento , Atletas , Desempenho Atlético/fisiologia
3.
Sleep Breath ; 27(3): 953-960, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-35922614

RESUMO

BACKGROUND: Adolescents with sedentary behavior, spending many hours in front of the television and electronic devices, develop early involvement of cardiovascular disease and obesity. These sedentary behaviors increased significantly in this age group during the pandemic of 2020/2021. Sleep directly influences aspects of health, such as blood pressure and cardiac autonomic balance and exercise has a protective effect on these same physiological parameters. OBJECTIVE: This study aimed to examine whether or not physically active adolescents positively influence HRV and cardiovascular parameters despite poor sleep quality. METHODS: This is an analytic and transversal study. Sleep quality, physical activity levels, blood pressure, and heart rate variability (HRV) were measured. Two-way ANOVA and Tuckey post hoc test evaluated the difference between groups. RESULTS: Among 352 adolescents entrolled, mean age was 15.8 ± 0.24 years. It was observed that compared to the physically active group with poor sleep quality, the sedentary poor sleep quality group presented a more significant deficit in blood pressure and autonomic parameters such as pNN50, SD1, and HF. CONCLUSION: Adolescents who practiced physical activity regularly have shown better HRV and sleep quality compared with sedentary adolescents.


Assuntos
Exercício Físico , Qualidade do Sono , Adolescente , Humanos , Exercício Físico/fisiologia , Sono/fisiologia , Obesidade , Coração , Frequência Cardíaca/fisiologia
4.
Percept Mot Skills ; 130(1): 485-496, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36227720

RESUMO

Volleyball is a popular sport in Brazil, and the relative age effect (RAE) is known to occur within it; but less is known of how RAE relates to elite Brazilian volleyball players' age, sex, and competitive levels. We aimed to investigate RAE prevalence with data from two seasons of play among players in the Superliga A (2020/2021 and 2021/2022 seasons), and Superliga B (2021 and 2022 seasons) made available from the Brazilian Volleyball Confederation (CBV), the club's official website, or direct consultation with the CBV. After removing duplicate data, we grouped these 1,063 athletes by their dates of birth, sex, and competition level (Superliga A or B). We divided players' birth dates into quarters (Q1: January-March, Q2: April-June, Q3: July-September and Q4: October-December) and into semesters, and we performed chi-square (χ2) tests to investigate RAE prevalence according to the players' sex and competitive level. RAE was prevalent overall (χ2 = 33.198; p < .001), among males (χ2 = 24.48; p < .001) and females (χ2 = 11.23; p < .011). Regarding competition level, RAE was evident among males in both Superliga A (χ2 = 14.581; p = 0.002), and B (χ2 = 13.985; p = 0.003), and among females in Superliga B (χ2 = 9.204; p = 0.027), but not Superliga A (χ2 = 4.012; p = 0.26). Thus, the RAE phenomenon operated differently for male and female Brazilian volleyball players according to their competitive level. We discuss the implications of these findings.


Assuntos
Voleibol , Humanos , Masculino , Feminino , Brasil/epidemiologia , Atletas
5.
J Hum Kinet ; 84: 148-157, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36457470

RESUMO

Athletes born closer to an arbitrary cut-off date are more likely to reach an elite level in sport, which is supported by a phenomenon called the relative age effect (RAE). It is important to determine whether this phenomenon is present in a sport to minimize this selection bias. This study aimed to investigate the prevalence of RAE in elite volleyball athletes, considering the influence of gender, the playing position (Setter, Middle, Libero, Opposite, and Outside Hitter) and the performance level (attack points, aces, and block points). The sample comprised 203 male and 193 female athletes competing in the Superliga A in the 2020/2021 season, which was equivalent to all of the teams of the championship. The data collection was performed during May and June, 2021. Athletes were organized according to gender, the playing position, and performance in the Superliga. For performance variables, athletes were separated based on the median value (90.0), and classified as high- or low-performance. Chi-squared tests were performed to verify differences between birth date distributions in relation to the aforementioned variables. Results indicated overrepresentation of relatively older male athletes (Q1 = 35.96%; Q2 = 27.59%; Q3 = 19.21%; Q4 = 17.24%), especially in Middles, Opposites, and Outside Hitters, regardless of their performance level. Considering females, no differences were found. Our findings suggest that RAE operates differently for men and women in elite Brazilian volleyball. The characteristics of the games played by male and female elite athletes may lead to different talent selection processes, affecting the likelihood of RAE prevalence.

6.
BMC Sports Sci Med Rehabil ; 14(1): 188, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36320067

RESUMO

PURPOSE: The aim of this study was to analyze the within-week differences in external training intensity in different microcycles considering different playing positions in women elite volleyball players. METHODS: The training and match data were collected during the 2020-2021 season, which included 10 friendly matches, 41 league matches and 11 champions league matches. The players' position, training/match duration, training/match load, local positioning system (LPS) total distance, LPS jumps, accelerations, decelerations, high metabolic load distance (HMLD), acute and chronic (AC) mean and AC ratio calculated with the rolling average (RA) method and the exponentially weighted moving average (EWMA) method, monotony and strain values were analyzed. RESULTS: All the variables except strain, Acc/Dec ratio and acute mean (RA) showed significant differences among distance to match days. Regarding the players' positions, the only difference was found in the AC ratio (EWMA); in all microcycles, the middle blocker player showed workload values when compared with the left hitter, setter and libero. CONCLUSION: Overall, the analysis revealed that the intensity of all performance indicators, except for strain, acc/dec and acute mean load (RA), showed significant differences among distance to match day with moderate to large effect sizes. When comparing players' positions, the middle blocker accumulated the lowest loads. There were no significant differences among other positions.

7.
Biol Sport ; 39(4): 995-1010, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36247946

RESUMO

Studies on small-sided games (SSG) in team sports have increased in recent decades. However, the literature concerning this training strategy in volleyball is sparse. This study aims to summarize and analyse the scientific evidence on SSG in volleyball. For this purpose, electronic searches were conducted in August 2021 in PubMed, Scielo, ScienceDirect, Scopus, SPORTDiscus, and Web of Science databases. As result, a total of 22 studies (3 cross-sectional, 7 quasi-experimental, and 12 randomized controlled trial) that used SSG in volleyball were included in the qualitative synthesis after applying the eligibility criteria. Despite the few studies available for each outcome, our results suggest that the SSG can be used as a methodological resource for volleyball teaching and training of educational, recreational, and high-performance character. In conclusion, the use of SSG in volleyball is a pedagogical and training alternative with positive effects on populations with different levels of training (school and university students, recreational adult players, and athletes) considering instructional approaches, sport knowledge, participation in Physical Education classes, health markers, physical fitness, and physiological, psychological, and tactical-technical variables. However, more studies need to be carried out using SSG in volleyball in different contexts, with different manipulations and variables.

8.
Artigo em Inglês | MEDLINE | ID: mdl-35886543

RESUMO

The purpose of the study was to test the within-week variations of the internal and external training intensity outcomes organized by days of the week. An 8-month observational period was conducted during the 2020-2021 season. The training sessions and matches of an elite volleyball team were monitored daily. The data comes from 14 players (two setters, five middle blockers, five outside hitters, and two opposites) of an elite team from the Portuguese 1st League (age: 21.7 ± 4.19 years of age; experience: 6.2 ± 3.8 years; body mass: 85.7 ± 8.69 kg; height: 192.4 ± 6.25 cm; BMI: 23.1 ± 1.40 kg/m2). The CR10 Borg scale was applied daily to measure the training intensity. The rate of perceived exertion (RPE) and the session-RPE were extracted as the internal outcomes. The external intensity was measured using an inertial measurement unit (IMU). The number of jumps, height average of jumps (JHA), minimum jump (MJ), maximal jump (MXJ), range jump (RJ), number of jumps (NJ), and training session density (D) were extracted as external intensity outcomes. The results showed that there was a difference between RPE and S-RPE (F (1.98) = 6.31, p = 0.01, η2 = 0.36, and F (1.73) = 28.30, p = 0.001, η2 = 0.72), as well as JHA and NJ (F (2.14) = 4.76, p = 0.02, η2 = 0.30, and F (1.77) = 4.77, p = 0.02, η2 = 0.30) within the microcycle. When analyzing the correlations between internal and external intensity, it was observed that there was a negative correlation between the Maximum Jump (4, 3, and 1 days before the Match day) (r2 = 0.34, r2 = 0.40, r2 = 0.41, respectively) and the Range Jump (3 and 1 days before the Match day (r2 = 0.33, r2 = 0.38, respectively) with the RPE (4 days before the Match day) and Maximum Jump (5, 4, 3, and 1 days before the Match day (r2 = 0.35, r2 = 0.39, r2 = 0.44, r2 = 0.34, respectively) and Range Jump (5, 4, 3, and 1 days before the Match day) (r2 = 0.34, r2 = 0.35, r2 = 0.40 and r2 = 0.36, respectively) with S_RPE (4 days before the Match day). Such findings show that higher internal intensities are correlated with lower external intensities in sessions further away from the game day. Such results could be an important tool for coaches to reflect, plan, monitor, and execute the training unit according to the temporal distance to the competition.


Assuntos
Desempenho Atlético , Voleibol , Adolescente , Adulto , Criança , Pré-Escolar , Humanos , Masculino , Estações do Ano , Adulto Jovem
9.
Percept Mot Skills ; 129(4): 1193-1209, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35477325

RESUMO

Our purpose with this study was to analyze construct validity evidence for the Motor Coordination Test with Ball (MCTB). Our participant sample included 1620 students (741 girls; 879 boys) aged between 10-12 years. Evidence for construct-validity of the four tasks using exploratory factor analysis (EFA) and adequacy indices confirmed a good fit of a final two-dimensional model (BTS = .000; KMO = .83; loading .53 to .91; communalities ranging from .31 to .86; explained variance of 63.5%; goodness-of-fit index (GFI) = .99; adjusted GFI (AGFI) = .97; RMSR = .03), and confirmatory factor analysis (CFA) (X2/df = 4.9; GFI = .97; comparative fit index (CFI) = .92; TLI = .90; Root-Mean-Square Error of Aproximation (RMSEA) = .03). We concluded that, in a Brazilian sample, the MCTB has good construct validity for motor coordination tests with balls; this helps qualify this test for use in schools and in the sports context.


Assuntos
Instituições Acadêmicas , Estudantes , Brasil , Criança , Análise Fatorial , Feminino , Humanos , Masculino , Psicometria , Reprodutibilidade dos Testes , Inquéritos e Questionários
10.
Motriz (Online) ; 28: e10220002022, 2022. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1386370

RESUMO

Abstract Aim: To investigate the existence of relative age effect (RAE) in Brazilian water polo athletes according to sex and age category. Methods: The birthdate of 574 Brazilian water polo athletes were organized according to the athletes' birthdates into quarters of the year (Q1, Q2, Q3, and Q4), and classified according to sex (male and female) and age category (U16, U18, U20, and senior). To verify the existence of RAE, the Chi-Square tests (χ2) were performed, and the effect sizes (ω) were calculated for each of the tests. We also calculated odds ratio (ORs) and 95% confidence intervals, setting the level of significance to 0.05. As post hoc analysis, multiple comparisons between quarters were performed, with Bonferroni's correction (significance level set to 0.0083 in these cases). Results: The results indicated an uneven distribution of birthdates for male water polo athletes (χ2 = 12.257; p = 0.007; ω = 0.173), with an overrepresentation of athletes born in the first (p < 0.006) and second (p < 0.002) quarters. When sex and age category were considered, male athletes presented uneven distributions in U20 (χ2 = 10.747; p = 0.013; ω = 0.345) and senior (χ2= 12.614; p = 0.006; ω = 0.383) categories. In females, no differences were found. Conclusion: We conclude that there is an uneven distribution of birthdates in male Brazilian water polo athletes, indicating the presence of RAE in this group.


Assuntos
Humanos , Aptidão , Fatores Etários , Atletas , Esportes Aquáticos/tendências , Epidemiologia Descritiva , Estudos Retrospectivos
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