Percentile norms for the 10x5-meters shuttle run test in a large sample of primary school-aged children: A cross-sectional study

Purpose: In the preceding two decades, comprehensive documentation pertaining to reference standards of health-related physical fitness of school-aged children has emerged. However, prevailing research has mainly concentrated on the establishment of muscular and cardiorespiratory metrics, neglecting certain physical fitness components (notably, motor fitness) for which reference standards have yet to be formulated. Therefore, the main objective of this study was to construct reference standards for the 10x5-meters shuttle run test for Croatian primary school-aged children. Methods: In this cross-sectional study, the participants were 1.512 healthy children and adolescents residing in the urban area of the city of Zagreb, Croatia (mean age: 9.7 years, range 7-14 years; mean height: 151.0 cm, range 138-173 cm; mean weight: 45.1 kg, range 32-60 kg; 52.5% girls). Sex- and age-specific variations, as well as effect sizes (ES), were investigated through the application of analysis of variance within the study framework for the 10x5-meters shuttle run test. Results: he median scores for the 10x5-meters shuttle run test were 22.1 seconds for boys and 23.2 seconds for girls. Sex- and agespecific analyses revealed statistically significant differences, indicating that boys achieved better results compared to girls (F-1,F-15 = 36.06, P< .001; ES = .33). Additionally, older boys and girls outperforming their younger counterparts (F-1,F-15 = 30.32, P< .001; ES = .45). Finally, the interaction between sex and age remained significant (F-1,F-15 = 2.50, P= .015; ES = .24), underscoring that older boys were faster in completing the task when compared to individuals of other sex and age groups. Conclusions: This study revealed discernible sex- and age-related disparities in the 10x5-meters shuttle run test among primary school children. These findings imply that chronologically younger children, particularly younger girls, achieved lower scores. Consequently, these findings underscore the necessity of targeted interventions to enhance speed and coordination/agility abilities in the aforementioned demographic subgroups.