Relative age effects despite weight categories in elite junior male wrestlers

Relative age effect in male and female elite international amateur boxing

This study aimed to determine whether the Relative Age Effect (RAE) was present in different sexes and age categories in 12 elite-level international amateur boxing competitions. A total of 4813 athletes competing between 2013 and 2022 were analysed. Athletes were split into four quartiles according to their birth date and compared to the expected (equal) birth date distribution using chi-squared goodness of fit. The results revealed greater RAE prevalence in youth compared to the senior group. RAE was more prominent in males compared to females, with the female group showing an inverse RAE trend. Odds ratio (OR) showed an overrepresentation of male boxers born in Q1 compared to Q4 (OR > 1.19-1.33), while senior female boxers presented an inverse trend (OR < 0.95). Odds Ratios for medallists within the youth group were greater than 1.07 (except Q3 × Q4 = 0.93) highlighting an overrepresentation of boxers born earlier in the year. A shift in strategy to reduce the RAE in young boxers whereby coaches focus less on the short-term pursuit of sporting success is encouraged. Organisations and coaches should increase awareness and provide systematic education around RAE, whilst creating equal competitive opportunities for all young boxers to reduce the extent of RAE in boxing.

Relative Age Effects in Elite Olympic Weightlifters

ABSTRACT

Kollars, JM, Taber, CB, and Beyer, KS. Relative age effects in elite olympic weightlifters. J Strength Cond Res 35(5): 1223-1228, 2021-The time of year in which an athlete is born may provide an advantage developmentally for competition, known as relative age effects (RAEs). The presence of RAEs in sport may result in athletes participating less or leaving the sport early. To determine if RAEs exist in elite Olympic weightlifting, data were examined from the past 5 Olympic Games. Using retrospective competition data, a total of 953 weightlifters (595 men and 358 women) who competed in the Olympic Games between 2000 and 2016 were included in this study. Athletes were divided into lightweight, middleweight, and heavyweight for analysis. Using the subset weight classes, the observed date of birth distribution vs. the expected worldwide date of birth distribution were compared using multiple chi square tests. Relative age effects were present overall for weightlifters (χ2 = 189.428, p < 0.001), with over-representation in January (z = +12.6, 20.9%) and under-representation in June (z = -2.1, 6.3%), September (z = -3.2, 5.7%), and November (z = -3.0, 5.1%). Relative age effects were also present in men lightweight (χ2 = 74.773, p < 0.001), men middleweight (χ2 = 41.786, p < 0.001), men heavyweight (χ2 = 39.395, p < 0.001), and women lightweight (χ2 = 37.251, p < 0.001). Determining that RAEs are present in weightlifting is important because it will help maintain the amount of opportunity for all athletes regardless of when they were born in the year. Coaches should be aware of the possible advantages of training age and the effect of physical maturation as a result of these RAEs. Coaches may use this information for athlete selection, but the presence of RAEs should not discourage athletes from participating in the sport of weightlifting.

Relative Age Influences Performance of World-Class Track and Field Athletes Even in the Adulthood

The relative age effect (RAE) is a common phenomenon observed in youth sports and is characterized by a significant over-representation of athletes born close to the date of selection. However, there is a lack of research on RAE in world-class track and field athletes and it is not clear if this effect persists into adulthood. Thus, this study examined for the first time the prevalence and magnitude of RAE at world class level in all track and field disciplines. Birthdates of 39,590 athletes (51.6% females) ranked in the International Association of Athletics Federations top 100 official lists between 2007 and 2018 season of Under 18, Under 20, and Senior categories were collected. Under 18 and Under 20 athletes born in the first week of the year are about 2 to 3.5 times more likely to be included in the top-100 ranking than the athletes born in the last week of the year. RAE was overall larger in male compared to female athletes. In some disciplines (e.g., throwing events) RAE persists in Senior category. These findings suggest that in some disciplines relatively younger athletes may have less chances of reaching world-class performances even in the adulthood. Governing bodies should reflect upon their policies for athlete support and selection to minimize the RAE.

The relative age effect is larger in Italian soccer top-level youth categories and smaller in Serie A

The relative age effect (RAE; i.e., an asymmetry in the birth distribution) is a bias observed in sport competitions that may favour relatively older athletes in talent identification. Therefore, the aim of this study was to investigate the presence of RAE in elite soccer players competing in the Italian championships, even considering the discriminations of younger and older Serie A players (in relation to the median age of the sample), and different positional roles (i.e., goalkeeper, defender, midfielder, forward) for each observed category. A total of 2051 players competing into the 2017–2018 Italian under-15 (n = 265), under-16 (n = 362), under-17 (n = 403), Primavera (n = 421) and Serie A (n = 600) championships were analysed. The birth-date distributions, grouped in four quartiles (i.e., January-March, Q1; April-June, Q2; July-September, Q3; October-December, Q4), were compared to a uniform distribution using Chi-squared analysis. The week of birth was analysed using Poisson regression. The results showed a large over-representation of players born in Q1 in all soccer player categories. However, the effect size of this trend resulted smaller as age increased. Individuals born in Q1 have about two-folds more chances to become a Serie A player compared to those born in Q4. The Poisson regression analysis showed that RAE was greater for defenders than for forwards among all categories. Therefore, a strongly biased selection emerged among elite soccer players competing in Italian championships, highlighting how young individuals born in the first three months have many more chances to become elite players compared to the others.