Association of leisure time physical activity and sports competition activities with high blood pressure levels: study carried out in a sample of portuguese children and adolescents

Abstract
A better understanding of the different domains and characteristics of children's and adolescent's physical activity (PA) could be a strategy to clarify the association of this behaviour with the early development of cardiovascular risk factors. To examine the relationship between leisure time physical activity (LTPA) and sports competition activities (SCA) with high blood pressure (HBP) levels in a sample of children and adolescents from Porto, Portugal. This is a cross-sectional study, which comprised 503 boys and 572 girls, aged 8-17 years old. LTPA and SCA were assed by self-reported. Students were assigned as active and non-active in SCA or LTPA according to their self-reported participation. Participants were classified as HBP when they are above of the last quartile for systolic and/or diastolic BP adjusted for gender and age. Do not be engaged in LTPA (OR: 1.47; 95% CI: 1.12; 1.93) and SCA (OR: 1.36; 95% CI: 1.02; 1.81) was significantly associated with the likelihood of being HBP. However, when cardiorespiratory fitness (CRF) (OR: 1.23; 95% CI: 0.91; 1.67) and body mass index (BMI) (OR: 1.31; 95% CI: 0.98; 1.75) were included on SCA model, the association between SCA with HBP did not showed significant results. Children and adolescents who are not engaged in SCA or LTPA are more likely to be classified as having HBP; however, the relationship between SCA and HBP was dependent of CRF and BMI. Further, PA strategies should take these differences on the relationship between HBP, SCA and LTPA.