Associations between Agility, the Relative Age Effect, Siblings, and Digit Ratio (D2:D4) in Children and Adolescents.

BACKGROUND

This study aims to analyze the influence of relative age effects, siblings, and digit ratio on the agility of children and adolescents.

METHODS

The study included 283 children (9.54 ± 1.36 years) and 296 adolescents (14.68 ± 1.36 years) from four different schools. The analyzed variables included anthropometric data, the presence of siblings, relative age effect, and results from the 10 × 5 m shuttle run test.

RESULTS

The findings indicated no significant association between agility and either the 2D:4D ratio or the relative age effect in both children and adolescents ( > 0.05). Additionally, having siblings did not have a notable impact on agility. Multiple regression analysis confirmed that relative age did not influence this lack of association (quarter of birth: = 0.345, β = 0.039; siblings: = 0.100, β = -0.069). However, boys showed higher performance than girls in the 10 × 5 m shuttle run test, and higher body mass index was related to lower agility.

CONCLUSIONS

These findings contribute to existing knowledge on the relative effects of age and provide valuable information for physical education teachers on the influence of the 2D:4D ratio and the presence of siblings on the physical fitness of children and adolescents.