Background: The purpose of this comparative and correlational cross-sectional study was to describe the associations between cardiorespiratory fitness, blood pressure and body composition in Portuguese school children.
Methods: The sample comprised 529 children (246 males and 283 females) aged 8-15 years-old. Body height and body mass were determined by standard anthropometric
Methods: Blood pressures were measured with children sitting after at least 5 min rest. The maximal multistage 20 m shuttle run test was carried-out to predict maximal aerobic power.
Results: The present study shows that boys were more fit (p= or <0.05) and less fat than girls (p= or <0.05). Multiple regression analysis reveals that weight and age explained significantly (p= or <0.01) the amounts of systolic blood pressure (SBP) and diastolic blood pressure (DBP). In girls, percentage of fat (%F) showed an influence on the variance in SBP (4.9%, p= or <0.05). In addition, weight (14.5%) and age (9.8%) account significantly (p= or <0.01) for the amount of variance to DBP in males. For girls, age (11.4%) and BMI (2.4%) account significantly to the variance found in DBP. However, the independent variables, for both sexes, account less than 50% of the overall variance found in blood pressures values.
Conclusions: In conclusion, the present study shows that boys were more fit and had less fat than girls. The level of cardiorespiratory fitness does not seem to be an important correlate of blood pressure variation across age groups and gender.