Relative age effect on anthropometry, biological maturation and performance of young soccer players

Abstract

The study examined the presence of the relative age effect (RAE) and association between birth quartile and anthropometry, biological maturation and physical and technical performance of young Brazilian soccer players. The sample included 119 male players, 74 of U-15 category and 45 of U-17 category, which were divided into quartiles according to the birth year. Biological maturation was assessed using the method of skeletal age of Fels. Anthropometric measurements included body weight, stature and subcutaneous adiposity. Physical fitness assessment included strength tests in the lower limbs, speed, aerobic endurance and anaerobic power. Technical skills included ball control, dribbling and kicking accuracy. Overall, 65.5% of soccer players were born on the first half of the year (c2= 8.069, p = 0.04); however, in the analysis by category, there was no significant difference in the distribution of birth dates for quartile when compared with the reference population (U-15: c2=6.322, p=0.10; U-17: c2=2.339, p=0.50). MANCOVA revealed no significant differences between anthropometry, biological maturation and physical and technical performance in both competitive categories. These results suggest that there is a higher proportion of young Brazilian soccer born on the first months of the year, but that RAE does not necessarily constitute an advantage under the anthropometric, physical and technical standpoint. The process of biological maturation of individuals should be considered by coaches in the selection of athletes.