Normative Values for Measures of Physical Fitness Among Tunisian School Children

Background This study aimed to (i) provide normative data for measures of physical fitness (PF) (i.e., muscle strength, muscle power, linear sprint speed) in 8- to 14-year-old Tunisian children and (ii) to examine sex and age group differences in these measures. Methods A total of 597 subjects (aged 8 similar to 14) participated in this study, the normative data for handgrip strength, jump height, and linear sprint speed were generated and collected, and the two-way analysis of variance (ANOVA) was used to identify the presence of the main effect of age, sex, an age x sex interaction for all tests. Results The two-way ANOVA showed credible age by sex interactions for all measures of PF [Effect Size (ES) ranged from 0.28 to 0.68; P < 0.05]. The findings indicated a main effect of age in handgrip strength, countermovement jump (CMJ) height, and linear sprint speed (all P < 0.05), regardless of sex. Post hoc analyses showed early increases in handgrip strength for boys from 8 to 14 years. For CMJ height, an increase in performance was observed from 10 to 11 years (ES = 0.23) and 12 to 13 years (ES = 0.14) (all P < 0.05). For linear sprint speed, performance enhancement was observed from 10 to 11 years (ES = 1.00). In girls, an increase in handgrip strength was noted from 9 to 12 years (ES = 1.00). However, the changes across age were less convincing for CMJ height and linear sprint speed tests, suggesting that differences for girls were not supported by the collected data. Boys outperformed girls in all measures of PF (P < 0.05). A summary of the estimated centiles of 10- and 30-m sprint speed, grip strength, and CMJ height for boys and girls allows a particular child's test values to be compared to the norms for the group. Conclusions In summary, this study provides normative data that can be used as a tool to classify sprint speed, strength, and jump height performance in children of both sexes aged 8-14 years.