Effect of Maturity Status and Relative Age Effect on Anthropometrics and Physical Performance of Soccer Players  Aged 12 to 15 Years

 Introduction: There is a growing interest in the relationship between biological maturation, relative age effect, and soccer sports performance. Based on their cohort's relative age effect and maturation, relatively older soccer players can be favored to be selected for high-level teams.  Therefore, the current study examined the effect of maturity and relative age on anthropometric and physical performance tests. Methods: A cross-sectional study involving 82 boys (M age: 13.4 ± 1.1; M body mass: 51.9 ± 9.9;   body height: 162 ± 10.5; body fat%: 9.7 ± 1.1) were assessed for anthropometric, flexibility, hand, and leg strength, and countermovement jump performance. Peak height velocity (PHV) determination was used for maturity status estimation. The birthdate distributions were categorized into four quartiles (January-March, Q1; April-June, Q2; July-September, Q3; October-December, Q4). MANOVA analysis was performed on all anthropometric and physical performance assessments to examine differences within age groups and maturity status groups. Differences among all groups were revealed, with high scores in the older group (U-15). Results: Biological maturation influences the differences in the anthropometric and physical performance assessment with a significant effect on the early matured soccer players compared to the late matured.  Early matured players were overrepresented and statistically had better anthropometric and physical performance results. Conclusion: However, there was no significant representation of players in the first quarter compared to the third and fourth quarters for all the anthropometric and performance assessments. The current findings can be used for quantifying and controlling performance data of soccer players adjusted to biological requirements used in the training process.