Search

Background: Cardiorespiratory fitness (CRF) is considered a beneficial effect of physical activity (PA). PA and excessive screen time have implications for cardiometabolic risk., Objective: To verify the association between screen time and CRF grouped by cardiometabolic risk factors., Subjects and Methods: Cross-sectional study evaluated 1,253 schoolchildren (54.2% girls) aged seven to 17 years from southern Brazil. The outcomes were body mass index (BMI), waist circumference (WC), systolic blood pressure (SBP), and diastolic (DBP), glucose, and lipid profile. Exposure was a combined variable of self-reported screen time (television, video game, computer) and CRF., Results: The main result is that CRF had a more consistent association with anthropometric factors than with metabolic variables. Low CRF students, regardless of screen time, showed a 15% increase in the risk of elevated WC ( p  < 0.001) and a 24% (<2 h screen time) and 19% (≥2 h) higher risk of overweight ( p  < 0.001). Second, the increase in SBP was associated with a combination of the two risk factors, ≥2 h screen time/low CRF was associated with a 7% increase in elevated SBP ( p  = 0.025)., Conclusion: Low CRF was a risk factor for elevated BMI and WC, regardless of screen time. High screen time and low CRF were associated with higher SBP values.

Background: There is a lack of clarity as to which obesity parameters may be more important in the association between cardiorespiratory fitness (CRF) and cardiometabolic risk factors (CMRF)., Aim: To verify the mediating role of different obesity parameters on the association between CRF and CMRF in normal weight and overweight/obese children and adolescents., Methods: This cross-sectional study comprised 999 children and adolescents (534 boys) aged 7-14 years from the south of Brazil. Body mass index (BMI), waist circumference (WC), waist-to-height ratio (WHtR) and percentage of body fat were assessed. Participants were classified as normal weight, overweight and obese according to BMI. CRF was evaluated by the 6-minute run/walk test. . A continuous CMRF score was calculated by summing the Z-scores of the following variables: systolic and diastolic blood pressure, glucose, total cholesterol, high-density lipoprotein cholesterol and triglycerides. Data analysis was performed using partial correlation and linear regression models., Results: BMI, WC, WHtR and percentage of body fat mediated the relationship between CRF and CMRF in overweight/obese boys and girls but not those of normal weight. Additionally, the percentage of the influence of each obesity parameter was 20% for BMI and WC, 16% for percentage of body fat and 18% for WHtR in girls. For boys, the mediation effect was 25% for BMI, 26% for WC, 28% for percentage of body fat and 25% for WHtR., Conclusion: Adiposity plays a central role in CMRF; therefore, maintaining an adequate weight status should be an important objective of health-promoting programmes in early age., Abbreviations : CMRF, cardiometabolic risk factors; CRF, cardiorespiratory fitness; BMI. body mass index; HDL-c, high-density lipoprotein cholesterol, PROCESS PROESP-Br, Projeto Esporte Brasil; SPSS, Package for Social Sciences; TC, total cholesterol; TG, triglycerides; WC, waist circumference; WHtR, waist-to-height ratio; %BF, percentage of body fat.