The Relative Age Effect and the Maadi Regatta

The relative age effect is a phenomenon in which children born in, or close to, a critical age cut-off period may have an advantage in athletic, academic and other endeavours. 

This page will be used to explore its relevance to age classification at the Maadi Regatta. As a retired teacher and coach I am on a learning curve with regard to this subject, so all meaningful comments, corrections and enhancements will be appreciated. Views expressed here are my own. 

References

Barnsley, R. H., Thompson, A. H., & Legault, P. (1992). Family planning of hockey players: The relative age effect. Journal of Sport Behavior, 15(2), 73–88.

Cobley, S., Baker, J., Wattie, N., & McKenna, J. (2009). Annual age-grouping and athlete development: A meta-analytical review of relative age effects in sport. Sports Medicine, 39(3), 235–256. https://doi.org/10.2165/00072567-200939030-00005

Eccles, J. S., & Barber, B. L. (1999). Student council, volunteering, basketball, and marching band: What kind of extracurricular involvement matters? Journal of Adolescent Research, 14(1), 10–43.

Jakobsson, J., Julin, A. L., Persson, G., & Malm, C. (2021). Darwinian selection discriminates against young athletes: The relative age effect in relation to sporting performance. Sports Medicine - Open, 7, Article 14. https://doi.org/10.1186/s40798-021-00300-2

Lawrence, S. (n.d.). Relative age effect. Balance is Better. Retrieved September 29, 2026, from https://balanceisbetter.org.nz/relative-age-effect/

McMaster, N. (2026). Age Group or Year Group classification. Age Group Rowing New Zealand. https://sites.google.com/view/maadi-age-group-rowing/age-groups-year-groups

McMaster, N. (2026). Rewiring the Maadi Regatta: Regatta Progression Systems Analysis. Independent Project Resource.
https://sites.google.com/view/maadi-age-group-rowing/rewiring-the-maadi-regatta-24-25

Musch, J., & Grondin, S. (2001). Unequal competition as an impediment to personal development: A review of the relative age effect in sport. Developmental Review, 21(2), 147–167. https://doi.org/10.1006/drev.2000.0516

Jakobsson, J., Julin, A. L., Persson, G., & Malm, C. (2021). Darwinian selection discriminates against young athletes: The relative age effect in relation to sporting performance. Sports Medicine - Open, 7(1), Article 20. https://doi.org/10.1186/s40798-021-00300-2

Ek, S., Wollmer, P., Karlsson, M. K., Peterson, T., Thorsson, O., Olsson, M. C., S. Malmborg, J., & Dencker, M. (2020). Relative age effect of sport academy adolescents, a physiological evaluation. Sports, 8(1), Article 5. https://doi.org/10.3390/sports8010005

Cumming, S. P., Searle, C., Hemsley, J. K., Haswell, F., Edwards, H., Scott, S., et al. (2018). Biological maturation, relative age and self-regulation in male professional academy soccer players: A test of the underdog hypothesis. Psychology of Sport and Exercise, 39, 147–153. https://doi.org/10.1016/j.psychsport.2018.08.006

New Zealand Rugby. (2024). National rugby policy: Policy #09. Age bands for age grade rugby. https://www.nzrugby.co.nz/assets/National-Rugby-Policy-Age-Bands-for-Age-Grade-Rugby.pdf

Slutzky, C. B., & Simpkins, S. D. (2009). The link in children's and adolescents' participation in sports: Friendships, peer socialization, and peer group acceptance. Journal of Youth and Adolescence, 38(3), 380–391. https://doi.org/10.1007/s10964-008-9324-4

Sport New Zealand. (2021). About Balance is Better: Supporting quality sport experiences for all young people. https://sportnz.org.nz/media/5253/about-balance-is-better-2_4.pdf

Vallerand, R. J., & Losier, G. F. (1999). An integrative analysis of motivation and sport settings. Advances in Motivation in Sport and Exercise, 83–119.

Augustine's College. (2026). Rowing Program Structure and Philosophy. Sydney, Australia. Available from St Augustine's College Sports Program.

Sydney Church of England Grammar School (Shore School). (2026). The Shore Rowing Programme: History, Tradition and Co-Curricular Structure. North Sydney, Australia. Available from Shore School Co-Curricular Rowing.

Another World. (2026, October 11) The "Winning Edge" Formula behind Rowing Coach - Michael Morgan’s STAGGERING success rate.

Another World

FootTech Academy. (2026, October 3) The Relative Age Effect & Early Developers: What Football Parents/Coaches Need To Know
FootTech Academy

Project Football. (2024) Why Birth Month Matters in Football Development Insights from Ajax Consultant Stephen Lawrence Project Football

Memeable Data. (2026, October 1) How Your Birth Month Impacts Your Success
Memeable Data

Athletic Evolution. (2026, October 4) Relative Age Effect In Youth Sport
Athletic Evolution 

Ontario Soccer. (2026, October 6) Webinar - Happy Birthday? The relative age effect in sport
Ontario Soccer

HPSI SG. (2026, October 9) Sean Cumming | Biological Maturation in Youth Sports: Breaking Biases
HPSI SG