Biological Maturity in Youth Athletes: Comparing Upper-Lower Body Ratios and Second Molar Eruption

Background: In youth sports, training and competition are traditionally structured based on chronological age. However, variations in biological maturity can lead to mismatches in competition, increasing the risk of injuries and affecting performance. Assessing biological maturity is essential for optimizing training strategies and ensuring fair competition. This study compares the effectiveness of upper-to-lower body measurements and second molar eruption in determining physical maturity in boys aged 10–14. Methods: A cross-sectional study was conducted on 20 male football players aged 10–14 years from the Unesa children's football club. Anthropometric measurements were taken to assess upper and lower body lengths, and the upper-to-lower body ratio was calculated. Dental maturity was evaluated based on the eruption status of second molars. Statistical analysis, including a one-sample t-test, was performed to compare these indicators against maturity benchmarks. Results: The mean upper body length was 73.22 cm, while the lower body length averaged 79.88 cm, yielding an upper-to-lower body ratio of 0.91, indicative of physical maturity. Second molar eruption assessment revealed that 90% of participants had fully erupted second molars, whereas 10% had incomplete dental development. A significant correlation was found between the upper-to-lower body ratio and second molar eruption, confirming their reliability in assessing physical maturity. Conclusion: The findings suggest that both upper-to-lower body measurements and second molar eruption provide reliable indicators of biological maturity in adolescent athletes. Integrating these assessments can enhance the accuracy of athlete classification, optimize training programs, and promote fair competition in youth sports. Future research should explore additional biological markers to refine age-group classifications further.