Relative age, referring to the chronological age differences between individuals within annually age-grouped cohorts, is regarded as influential to an athlete's development, constraining athletic skill acquisition. While many studies have suggested different mechanisms for this effect, they have typically examined varying sports, precluding an examination of the possible inter-play between factors. Our three studies try to bridge this gap by investigating several moderators for relative age effects (RAEs) in one sport. Handball is a sport with position-specific demands, high cultural relevance and a performance context with established developmental structures and levels of representation for males and females. In Study 1, we investigated the influence of competition level and gender on RAEs before adulthood. In Study 2, elite participation, player nationality and stage of career are considered during adulthood. In Study 3, playing position and laterality (i.e., right vs left handedness) are investigated as moderators. Collectively, the results emphasize the complex inter-play of direct and indirect influences on RAEs in sports, providing evidence toward explaining how RAEs influence the development and maintenance of expertise.

Researchers are only beginning to understand how contextual variables such as date of birth and birthplace affect the development of elite athletes. This article considers the generality of birthplace and date-of-birth effects in varying sport contexts. The Study 1 examined how environmental factors associated with an athlete's date-of-birth and size of birthplace predict the likelihood of becoming an Olympic athlete in Canada, the United States of America, Germany, and the United Kingdom. Study 2 examined date-of-birth and birthplace effects among athletes playing in the first professional league in Germany. Study 2 also examined the validity of birthplace as a proxy for early developmental environment by comparing birthplace with the place of first sports club in four German sports leagues. Results from both studies showed no consistent findings for date of birth. Findings from Study 2 also suggested incongruence between birthplace and location of first sports club as proxies for early developmental environment. Although there was some consistency suggesting elite athletes are less likely to come from very small or excessively large communities, exceptions occurred both within and across sport contexts. These results suggest that any developmental effects of date and place of birth are buffered by broader sociocultural factors.

Popular stereotypes of aging affect the performance of seniors in a number of different domains, from memory performance to physiological response. The authors undertook a review of this area, in which they examined 17 studies that looked at the impact of stereotype primes on older individuals' cognitive, physical, physiological and psychological performance. Analyses included investigating the effects of both positive and negative age stereotypes, and implicit and explicit priming methodologies. The authors utilized a meta-analytic technique on a subset of studies that examined the impact of priming on memory performance. This yielded an effect size of 0.38. The results suggest that popular stereotypes of aging (and the corresponding subtle changes in the testing environment) are important variables to consider for those researchers testing performance of seniors.

Relatively older children within ice hockey age groups are at increased risk of injury compared with their younger peers. Furthermore, the risk of injury for relatively older players is greater at more competitive levels of play. This study proposes that the relative age advantage associated with selection to Canadian youth ice hockey teams is accompanied by an increased risk of injury.