ABSTRACT
Abstract Introduction: The relative age effect is prevalent in different elite team sports. However, little is known about this phenomenon in high-level adult male futsal players. Aim: The present study aimed to investigate the prevalence of relative age effect in Brazilian male elite futsal players, and its relationship with playing position and goals scored on Brazil National Futsal Leagues (BNFL) from 2016 to 2020. Methods: The distribution of birth dates, playing positions, and goals scored by male participants of the Brazil National Futsal Leagues were analyzed. Chi-squared tests were used to analyze the birth dates distribution based on quarters and semesters of the year, according to playing position (defender, winger, pivot, and goalkeeper) and scoring performance (high and low). Results: The overall analysis indicated that the relative age effect is prevalent on the pool of athletes analyzed. However, this effect was position-dependent, since relatively older athletes were overrepresented only in wingers and defenders playing positions. On the other hand, scoring performance was not associated with the relative age effect, since this effect was found in both performance levels. Conclusion: Relative age effects are prevalent in Brazilian male elite futsal athletes, especially for defenders and wingers. Considering the high level of competitiveness for spots in elite futsal teams, coaches and sports administrators must be educated about the prevalence of the relative age effect in this sporting context. This is necessary in order to reduce the inequalities generated by age categories based on arbitrary cut-off dates, which may reduce potential talent loss.
Subject(s)
Humans , Male , Aptitude , Soccer , Age Factors , Athletes , Epidemiology, Descriptive , Retrospective StudiesABSTRACT
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.
Subject(s)
Humans , Aptitude , Age Factors , Athletes , Water Sports/trends , Epidemiology, Descriptive , Retrospective StudiesABSTRACT
The purpose of this study was to verify the date of birth is a decisive factor for the success of players selected by the coaches to participate in the FIFA U-17 World Cup Emirates 2013. The players' date of birth were classified into four quartiles of three months each (Q1 to Q4). In the qualifying round, 46.5% of the selected players born in Q1, while 12.5% in Q4. This significantly different distribution occurred until the semi-finals. However, in the final match, there were no significant differences between Q1 and Q4. A similar relative age effect also occurred when analyzed only players who actually participated to the matches. Interestingly, despite there was birth date effect on performance in all World Cup stages except in the final, other issues should take into consideration for a team became champion.
O objetivo deste estudo foi verificar se a data de nascimento é um fator decisivo para o sucesso de jogadores selecionados pelos treinadores para participar da Copa do Mundo Sub-17 Emirates 2013. As datas de nascimento dos jogadores foram classificadas em quatro quartis de três meses de cada (Q1 a Q4). Na qualificação, 46,5% dos jogadores selecionados nasceram em Q1, enquanto 12,5% em Q4. Esta distribuição significativamente diferente ocorreu até às semifinais. Entretanto, na final, não houve diferenças significativas entre Q1 e Q4. Um efeito similar da idade relativa também ocorreu quando analisados apenas os jogadores que efetivamente participaram das partidas. Curiosamente, apesar de haver efeito da data de nascimento sobre o desempenho em toda Copa do Mundo, exceto na final, outras questões devem levadas em consideração para uma equipe sagrar-se campeã.
La finalidad de este estudio fue verificar la fecha de nacimiento es un factor decisivo para el éxito de los jugadores seleccionados por los entrenadores para participar de la Copa Mundial sub-17 FIFA Emirados Árabes Unidos 2013. Fecha de nacimiento se clasificaron en cuatro cuartiles de tres meses (Q1 a Q4). En la qualificación, 46,5% de los seleccionados nacieron en Q1, mientras 12,5% en Q4. Esta distribución diferente ocurrió hasta las semifinales. Sin embargo, en la final, no hubo diferencias entre Q1 y Q4. Un efecto similar también ocurrió cuando se analizaron sólo los jugadores que efectivamente hugaron. Curiosamente, mismo con efecto de la fecha de nacimiento en toda la Copa Mundial, excepto la final, otros temas deben tener en cuenta para un equipo hacerse campeón.
Subject(s)
Humans , Male , Adolescent , Athletic Performance , Physical Fitness , Soccer , Time FactorsABSTRACT
Objective To investigate whether the monthly distribution of birth was associated with congenital heart disease(CHD).Methods The monthly distribution of birth of 5 070 patients with CHD who accepted examination or treatment from Jan.2003 to Dec.2006 was investigated and compared with that of 6 627 healthy newborn children born in 2001-2006.The statistic analysis was accomplished with SPSS 12.0 software for ?2 test.Results Four hundred and forty-four of the 5 070 patients with CHD were born in January(8.8%),432 cases in February(8.5%),384 cases in March(7.6%),339 cases in April(6.7%),390 cases in May(7.7%),393 cases in June(7.8%),414 cases in July(8.2%),489 cases in August(9.6%),498 cases in September(9.8%),492 cases in October(9.7%),396 cases in November(7.8%),and 399 cases in December(7.8%).The structural ratio of the number of CHD patients were the highest for those who were born in August,September,October,and the lowest among those who were born of February and March,April.The number of CHD patients who were born in the autumnal months of August,September and October was 1 479(29.1%),much higher than those who were born in February,March and April(1 155 cases,22.8%)(P