ABSTRACT
Relative age research in sports began with a casual observation at an ice hockey game that a disproportionate number of players were born early in the calendar year. Investigations of the rosters of other high-level hockey and soccer teams provided extensive and striking replication of this observation. Modest public and academic interest grew relentlessly to the present state where relative age effects (RAEs) in sports are the focus of researchers worldwide. Now, many sports have been examined and social structure and mental health factors have been implicated, pointing to a burgeoning potential for knowledge application that can either mute or harness this powerful effect.
