Investigation of the relationship between relative age and selected anthropometric and motor performance characteristics in children

Abstract Purpose: The purpose of this study was to examine the influence of the Relative Age Effect (RAE) on anthropometric characteristics and motor performance in children aged 7–14 years, with analyses conducted by age group and sex. Methods: A total of 7223 children (5404 boys and 1819 girls) receiving organized sports training in Istanbul participated in the study. Anthropometric measurements (height, body mass, and body mass index) and motor performance tests (agility, 20 m sprint and standing long jump,) were assessed using standardized procedures. Participants were classified into four birth quartiles based on month of birth. Data were analyzed separately by gender and age group using the General Linear Model (GLM) Univariate method. Results: Children born in the first and second birth quartiles were significantly taller and heavier than those born in the fourth quartile ( p < 0.01). Among boys aged 7–10 years, relatively older children demonstrated better sprint and jumping performance. In contrast, RAE-related differences in motor performance were less evident among girls. Conclusion: The findings indicate that RAE has a stronger influence on anthropometric growth than on motor performance, particularly in younger boys, whereas this effect appears less pronounced in girls and older age groups.