Association between time spent in sedentary,moderate to vigorous physical activity,body mass index,cardiorespiratory fitness and blood pressure

Background: Elevated blood pressure (BP) has been reported in young people and seems to be associated with body mass index (BMI) and reduced physical activity (PA).

Aim: This study sought to analyse the association of BP with BMI, PA intensity patterns and cardiorespiratory fitness (CRF) in youth.

Subjects and methods: A cross-sectional study was carried out including 66 boys (13.91±1.76) and 97 girls (14.02±1.71). Anthropometric characteristics, CRF and BP were assessed during school time and accelerometers were utilized to determine intensity of PA.

Results: The linear regression model, adjusted for age, sex and height, showed that higher values of BMI were associated (p≤0.05) with higher values of systolic blood pressure (SBP) (1.39; 95% CI: 0.56; 2.23) and diastolic blood pressure (DBP) (1.52; 95% CI: 0.68; 2.37). Additionally, SBP, but not DBP, was inversely associated (p≤0.05) with moderate PA (?0.25; 95% CI: ?0.47; ?0.02) and positively correlated with sedentary activities (0.04; 95% CI: 0.00; 0.08).

Conclusion: The present study showed that BMI and time spent in sedentary activities were inversely associated with SBP. However, time spent in moderate PA was positively associated with SBP. BMI was the single predictor of DBP.