Physical Fitness Trends Of Schoolchildren In A Municipality From Southern Brazil Between 2004 And 2017

Physical fitness is an important indicator of health, and low levels are associated with several diseases, such as obesity, dyslipidemia, and cardiovascular problems. Therefore, it is important to monitor physical fitness levels over the years. However, previous studies investigating physical fitness trends over the years reported contradictory findings. PURPOSE: This study aims to verify the physical fitness trends across multiple variables from 2004 to 2017 in schoolchildren in the municipality of Santa Cruz do Sul (RS), southern Brazil. METHODS: This was a trend study involving 11,005 randomly selected schoolchildren aged 6 to 17 years (11.50 ± 2.78 years; 53.3% female), recruited in 2004, 2008, 2011, 2014, and 2016. Physical fitness was assessed according to the Sport Brazil Project (Projeto Esporte Brasil; PROESP-Br) manual, through evaluation of upper and lower limb power, flexibility, abdominal muscle endurance, agility, and speed. Linear regression models were adjusted for sex and age. The years of evaluation were used as an independent variable to test whether changes in physical fitness occurred over the period. The results are presented in non-standardized coefficients (B) and 95% confidence intervals. RESULTS: An average increase was observed at each evaluation period in the indices of lower limb power (B: 0.007; 95%CI: 0.003; 0.010) and speed (B: 0.069; 95%CI: 0.061; 0.077) and a reduction in the indices of flexibility (B: −0.172; 95%CI: −0.269; −0.076), abdominal muscular endurance (B: −0.890; 95%CI: −0.993; −0.787), agility (B: −0.029; 95%CI: −0.040; −0.018) and upper limb power (B: −0.015; 95%CI: −0.024; −0.006). CONCLUSION: The students improved their performance of lower limb power and agility. On the other hand, there was a reduction in performance for speed, flexibility, abdominal muscle endurance, and upper limb power. These data are consistent with the literature, which indicates a constant decline in strength and endurance in children and adolescents over time. Conversely, the trend for agility and speed differs among populations. This emphasizes the importance of considering the differences between countries and an in-depth study of the factors that influence physical fitness levels since childhood. Supported by: Brazilian Agencies Foundation for Research Support of Rio Grande do Sul (FAPERGS)