Relative age effects (RAE) in sports refers to when the athletes are grouped by age which results in a difference in their performance and opportunities. Sports organizations decide who can participate based on birthdates and cutoff dates. If an athlete is born just after the cutoff date, they are considered older than those born just before it, even though they are in the same age group. The effects of RAE are often talked about in terms of one-year age differences. However, depending on the sport, the impact of these differences can be much longer and can vary depending on the sport.
Being relatively older can give athletes certain advantages in growth and development, making it more likely for them to be selected for sports teams. This leads to an overrepresentation of relatively older athletes in many sports, like ice hockey, football (soccer), handball, and basketball. While RAEs are most prominent in youth sports, they can still be seen at the elite adult level. The specific effects of RAEs depend on the characteristics of individuals, their environment, and the sport itself. Factors like being left-handed in tennis or having a smaller size in female gymnastics can influence whether older or younger athletes have the advantage.
Due to physical and emotional maturity, relatively older athletes also tend to perform better in physical education classes and other educational outcomes. RAEs can effect athlete dropout rates, opportunities to participate, and personal development in sports. To learn more about relative age effects see reviews by Musch and Grondin (2001) and Wattie, Schorer, and Baker (2015).
Musch, J., & Grondin, S. (2001). Unequal competition as an impediment to personal development: A review of the rela- tive age effect in sport. Developmental Review, 21, 147 167. Available from https://doi.org/10.1006/ drev.2000.0516.
Wattie, N., Schorer, J., & Baker, J. (2015). The relative age effect in sport: A developmental systems model. Sports Medicine, 45, 83 94. Available from https://doi.org/ 10.1007/s40279-014-0248-9.