Relative Age Effect in 14- to 18-Year-Old Athletes and Their Initial Approach to This Effect-Has Anything Changed Over the Past 10 Years?

Is There a Relationship Between Birth Quartile and Vertical Jump Performance Among Young Male Elite Volleyball Athletes?

Vertical jump is an important skill that influences volleyball performance. In this study, we analyzed the relationship between vertical jump performance and birth quartile of Brazilian male youth volleyball players. We calculated chi-square goodness-of-fit tests to compare the athletes' birthdate distributions in quarters of their birth years (Q1, Q2, Q3, and Q4) according to player age categories (U17, U18, U19, and U21). We calculated one-way ANOVAs to compare spike jump and block jump heights of players born in different quarters of the same year. Overall, we found a relative age effect (i.e., more players with birth dates early in the birth year) in U17 (p < .001), U18 (p < .001), U19 (p < .001), and U21 (p = .04). Regarding vertical jump performance, U18 athletes born in Q2 reached higher spike jump heights (p = .006) and block jump heights (p = .002) than athletes born in Q4, and U19 athletes born in Q1 reached higher block jump heights than athletes born in Q3 (p = .049). There were no significant differences in vertical jump performance across birth quartiles among U17 and U21 athletes. Thus, a relative age effect was present in all age categories but not always reflected in vertical jump performance. Volleyball coaches and policymakers are still advised to employ strategies to ensure fairer opportunities for players born later in the year of their eligibility dates, as we found RAE to be sometimes, but not always, related to higher spike or block jump heights even among these older adolescents and young adult athletes.

The Relative Age Effect in Male and Female Brazilian Elite Volleyball Athletes of Varied Competitive Levels

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.

Age and Maturation Matter in Youth Elite Soccer, but Depending on Competitive Level and Gender

This study aimed to explore the relevance of the relative age effect (RAE), maturity status and anthropometry, and their influence on coaches' assessment of players' performance, analyzing both genders and different types of academies (elite vs. non-elite). The sample included 603 soccer players (385 male), from the under 12 (U12), under 14 (U14) and under 16 (U16) categories, belonging to elite and nonelite teams. Coaches' assessment of players' performance, chronological age, anthropometric characteristics, maturity offset (MO) and peak height velocity (PHV) were registered. Our results showed that RAE was present in both genders within the elite, but not in the nonelite academies. Early maturity players were overrepresented in the male elite, but not in the female academies. No relationship was found between RAE and anthropometry in male elite academies. Male elite players showed better anthropometric characteristics than nonelite players, while this pattern of results was not found for female players. The coaches' assessment on players' current performance was not influenced by the chronological age nor anthropometry, but it was linked to the PHV. Coaches from nonelite academies rated better in current assessment of performance the taller players. Our findings suggest that maturity status and RAE play an independent and important role in the talent selection process.

Prevalence of the Relative Age Effect in Elite Brazilian Volleyball: An Analysis Based on Gender, the Playing Position, and Performance Indicators

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.

Low prevalence of relative age effects in Luxembourg’s male and female youth football

The relative age effect (RAE) is a well-established phenomenon in football. However, while the majority of previous studies focussed on established football nations, it remains unclear if the constraint of a limited population of soccer players in smaller countries associated with less strict selection procedures may reduce the risk of RAE. This study aims to investigate the RAE in Luxembourg that follows an ‘open-door’ selection policy in youth football due to the limited pool of players. Birthdates from all licensed and actively playing Luxembourgish youth footballers including all players of the youth national teams (396 girls and 10981 boys) competing in the season 2018/2019 were analysed and categorised into birth quarters and semesters. To further investigate a performance dependence of the RAE in amateur leagues, success was determined based on the teams’ rankings at the end of the season. Differences between observed and expected birthdate distributions were calculated across all licensed players and age groups, within the national teams, and for the top- and bottom-tier football teams using chi-square statistics. While a RAE was absent across all age groups (except U7), significant RAEs with high effect sizes were observed in the top-level and national teams. These findings contrast the substantial RAE effects in large football nations and suggest that open selection systems might reflect an environmental constraint that limit the prevalence of RAE in football. Further, this study indicates that a performance dependence of the RAE is not limited to high level football but already occurs on an amateur level.

The relative age effect in the Gaelic Athletic Association (GAA): A mixed methods approach

In the Gaelic Athletic Association (GAA), Talent Academies (TAs) and senior teams cater for high performing players, however only two previous studies have quantified the relative age effect (RAE; i.e., a selection bias favouring those born near the beginning of the cut-off date) in these cohorts. Additionally, no studies to date have explored stakeholder understanding of the RAE using qualitative methods. This study aimed to: (a) quantify the RAE in TAs and senior teams, and (b) investigate stakeholder perspectives of the talent development environment, providing practical insight into the RAE. A mixed methods sequential explanatory study design was employed. Phase one involved a retrospective analysis of longitudinal data for the frequency and distribution of births using TA (n=12,445) and senior (n=8,752) players. Phase two comprised two focus groups of key stakeholders [coaches (n=4) and Talent Development Leaders (n=4)] at TA and senior level. Analysis revealed a significant difference between TA birth quarter (BQ) distributions compared with expected distributions across all age groups (P<0.001; BQ1=30.4% vs. BQ4=17.6%), while at senior level, there were no significant differences between observed and expected BQ distributions (χ² (df=3) =3.812, P=0.282). In phase two, inductive analysis revealed three higher order themes: (a) understanding of the RAE, (b) selection criteria, and (c) player characteristics. The GAA are encouraged to reflect on the practice of chronological age band grouping, investigate possible solutions to limit the effects of the RAE, and offer support programmes to educate key stakeholders on the potential impact of the RAE on talent development.

The Birthplace Effect in 14–18-Year-Old Athletes Participating in Competitive Individual and Team Sports

The birthplace (the place where an athlete was born) effect (BPE) has been found to be one of the environmental variables associated with early talent development and the achievement of a high level of proficiency in sport. The purpose of the current study is twofold: (1) to calculate the BPE in 14–18-year-old athletes who participated in individual and team sports and (2) examine how coaches perceived this effect. The participants were 1397 athletes (390 females and 1007 males) who competed in 5 individual (gymnastics, judo, swimming, tennis, and track and field) and 5 team (basketball, soccer, team handball, volleyball, and water polo) sports, as well as 147 coaches who provided their preliminary thoughts about the BPE. Data analyses revealed that although the BPE was not found to be associated with cities of a similar size, it was observed that growing up in cities of small and medium sizes was more beneficial than growing up in towns or cities of other sizes. Most of the coaches believed that certain characteristics of the place or city where the athlete grew up (e.g., proximity to sport facilities) could contribute positively to the athlete’s development. We discuss how the BPE data can aid policymakers in developing a sport policy associated with early phases of talent development.

Exploring Relative Age Effects in Youth Ice Hockey Through a Single Team Case Study and Composite Narratives

Relative age effects (when birthdate influences participation or performance) in sport potentially influence the experiences of sport participants, including athletes, parents, and coaches. Nearly all existing literature on relative age effects adopts a quantitative approach, limiting our understanding of the phenomenon. Thus, the purpose of this unique study was to explore relative age effects using an instrumental, descriptive case study approach with one elite, youth, male ice hockey team. This context was chosen given the high prevalence of relative age effects among such groups. Participants included 20 athletes, 19 parents, and two coaches from one team. Data were collected through biometric measures, semistructured interviews, and participant observations. Results were presented as five composite narratives: relatively older athletes, relatively younger athletes, parents of relatively older athletes, parents of relatively younger athletes, and coaching staff. The narratives demonstrated unique relative age experiences for each group of participants. Discussion aligns the results with the social agents model that explains relative age effects. Practical recommendations for sport participants are also provided.