RELATIONSHIP BETWEEN PHYSICAL FITNESS AND BODY COMPOSITION IN PRIMARY SCHOOL CHILDREN IN NORTHERN SPAIN (LOGRONO)

Introduction: Childhood obesity is an epidemic that is more prevalent in developed countries, but the negative effects it has on children's health could be decreased by good physical fitness. Objectives: The aim of this study was to determine the level of physical fitness of a group of school children in a city in the North of Spain (Logrolio, La Rioja), and to analyze the relationship with the body composition, blood pressure and various socio-demographic factors. Methods: Research was conducted with a representative sample of 329 students aged 11-12 from all 31 schools of the city. Data included their socio-demographic background, anthropometric measurements, blood pressure, biological maturity and physical fitness. Results: Male students and students with normal body weight fared better in physical fitness tests than females and than those who suffered from overweight or obesity. 88% of boys and 80% of girls were found to have healthy aerobic capacity, while only 73% of immigrant children demonstrated this. A major risk of suffering from overweight or obesity was associated with inferior results in physical fitness tests, finding inverse relationships between the percentage of body fat and maximal oxygen uptake (r = -0.524), lower-body explosive strength (r = -0.400) and speed performance (r = 0.385). Conclusions: The relationship between physical fitness and body composition demonstrates the importance of intervening in order to improve physical fitness, especially with respect to aerobic capacity, with special emphasis needed for immigrant and female students.