The University of Bath, in partnership with the University of Edinburgh, has conducted the most extensive growth and maturation study in world football, helping reshape talent development pathways for young players in Scotland.
Commissioned by the Scottish Football Association (SFA) and completed between January and April 2024, the research , published in the Journal of Sports Sciences, evaluated over 1,000 academy players in the Club Academy Scotland (CAS) system - making it the largest study of its kind examining both relative age and biological maturation.
Researchers recorded players' birth dates, current height and weight, and parental height to project growth and determine biological maturity. The findings confirm a strong bias toward early-developing players, echoing global trends and raising important questions about current selection and development practices.
Professor Sean Cumming , Lead Researcher from the Department for Health, University of Bath, said:
"Academies are often populated by players who have simply matured earlier. This project and the new pilot rule allow us to create more equitable environments for all players to thrive - especially late developers, who are typically underrepresented."
Based on the findings, the Scottish FA has introduced a pilot policy that increases flexibility for clubs to group players based on biological rather than chronological age.
This aims to give later-developing players a fairer developmental environment, helping them build confidence and hone their skills alongside physically similar peers.
The pilot was announced at the Growth and Maturation Workshop held at Hampden Park, where researchers presented the data to clubs and academy staff.
Steve Curryn, Scottish FA PhD Researcher from the University of Bath, said:
"Only around 80% of boys were developmentally aligned with their calendar age. Some players in the same age group differed biologically by up to six years. This discrepancy can profoundly impact how players are perceived, selected, and coached."
In one case, a 13.8-year-old player had a biological age of 12.3, while another aged 15 measured biologically at 18 - highlighting the immense variability coaches must navigate. The study found that late developers, who make up around 15% of the population, were vastly underrepresented in the academy system.
Mark Leslie, Sports Science & Data Manager, Scottish FA, said:
"The University of Bath's expertise has provided us with an unprecedented insight into growth and maturation in elite youth football. We're confident this research will have lasting impact not only in Scotland but across global talent pathways."
The research supports broader findings in the Scottish FA's Transition Phase Report (2024), which outlined a need for more education and support during the critical growth spurt period in youth development. The pilot policy will allow clubs to request exemptions to move players across age groups based on biological maturity—lifting the previous cap of three players and allowing a more tailored approach to long-term athlete development.
The study also looked at successful late developers in elite football- such as Andy Robertson, Scott McTominay, John McGinn, and internationally, Rodri and Kevin De Bruyne - to underscore the potential being overlooked under current models.
Next Steps: Injury Prevention Phase
The next phase of the project will investigate the relationship between growth and injury incidence in academy football. Selected CAS clubs will now track injury rates alongside growth and maturation data to better understand risks during rapid development phases.
Informed by this data, the University of Bath will support the design and rollout of a growth-spurt-specific injury prevention intervention, which will include:
- Adjusted training loads
- Skill-based progressions
- Individualised strength and conditioning
The programme draws inspiration from a successful pilot at AFC Bournemouth , where injury rates dropped by 86% and injury burden fell by 90%.
Professor Sean Cumming added:
"This research is about levelling the playing field. Late developers often have to work harder, possess stronger technical or psychological attributes, yet still go unrecognised. This work allows us to support those players, reduce injury risk, and create more equitable development environments across football."
The University of Bath's work will contribute to an upcoming strategic review of elite youth development within Scottish football, ensuring the findings inform future evidence-based policy and practice across academies and national programmes.
This research is part funded by lead authors host institution (University of Bath) and the Scottish Football Association.
