Do Individual and School Characteristics Influence the Siblings’ Resemblance of Gross Motor Coordination Among Brazilian Youth?

Objectives This study aimed to investigate the degree of siblings’ resemblance in gross motor coordination (GMC), and to estimate the influence of individual and school context factors on siblings’ resemblance in GMC among Brazilian children. Methods The sample comprised 626 siblings (5–15 years; 48.72% girls) from Lagoa do Carro, Brazil. GMC was assessed using the Korperkoordinationtest für Kinder (KTK) battery. Body mass index, biological maturation, health- and performance-related physical fitness, and school characteristics (e.g., school´s physical structure and policies and practices related to physical activity and sports) were also obtained. Intraclass correlations were calculated for each of the three sibling types: Brother-Brother (BB), Sister-Sister (SS), and Brother-Sister (BS). Multilevel modeling was performed using the Bayesian approach. Results In general, sibling intraclass correlations varied between sibling types for all GMC tests. BB pairs had a higher resemblance in the moving sideways test, while SS pairs showed a higher resemblance in the walking backward and jumping sideways tests. BS pairs had a higher resemblance in the hopping for height test. For the GMC total score, BB and SS pairs had similar intraclass correlations. However, they showed a higher resemblance than BS pairs. Further, both individual and school characteristics influenced the magnitude of sibling resemblance. Conclusion Individual and school characteristics are associated with different GMC traits and influence the magnitude of intrapair variance.