The interaction between constituent year and within-1-year effects in elite German youth basketball

The current state of research on relative age effects in basketball shows an uneven picture. These mixed results might be caused by the interaction of constituent year and within-year effects. Our aim was to examine constituent and within-1-year effects in elite German youth basketball. The sample (n = 4400) included players competing in the JBBL (Under-16 first division) and the NBBL (Under-19 first division) from 2011/2012 until 2013/2014. A multi-way frequency analysis revealed an interaction of constituent year effects and within-1-year effects for the JBBL, χ² (6, 2590) = 12.76, P < 0.05. NBBL data showed significant constituent year effects, χ² (2, n = 1810) = 25.32, P < 0.01, and within-1-year effects for all three age bands but no interaction. The interaction between constituent year and within-1-year effects in the JBBL showed reduced within-1-year effects with increasing age. Once players enter the system in the JBBL, relatively younger players seem less likely to drop out of the system. Results offer new insight regarding how the regulations of this talent development system may influence athletes' opportunities to enter the system and their likelihood of staying at the highest levels of competition.

Does Relative Age Affect Career Length in North American Professional Sports?

Background

Relative age effects (RAEs) typically favour older members within a cohort; however, research suggests that younger players may experience some long-term advantages, such as longer career length. The purposes of this study were to replicate previous findings on RAEs among National Hockey League (NHL) ice hockey players, National Basketball Association (NBA) basketball players and National Football League (NFL) football players and to investigate the influence of relative age on career length in all three sports.

Methods

Using official archives, birthdates and number of games played were collected for players drafted into the NBA (N = 407), NFL (N = 2380) and NHL (N = 1028) from 1980 to 1989. We investigated the possibility that younger players might be able to maximize their career length by operationalizing career length as players’ number of games played throughout their careers.

Results

There was a clear RAE for the NHL, but effects were not significant for the NBA or NFL. Moreover, there was a significant difference in matches played between birth quartiles in the NHL favouring relatively younger players. There were no significant quartiles by career length effects in the NBA or NFL.

Conclusions

The significant relationship between relative age and career length provides further support for relative age as an important constraint on expertise development in ice hockey but not basketball or football. Currently, the reason why relatively younger players have longer careers is not known. However, it may be worth exploring the influence of injury risk or the development of better playing skills.