Fitness and fatness in children and adolescents: investigating their role in the association between physical activity and cardiometabolic health.

To verify the role of the combination of fitness and fatness in the relationship between physical activity (PA) and cardiometabolic risk in children and adolescents. This is a cross-sectional study performed with 2786 children and adolescents (6 to 17 years). Fitness was determined by the cardiorespiratory fitness (CRF) six-minute walking and running test. Waist circumference (WC) was considered a fatness indicator. A selfreported questionnaire was used to determine PA practice, whereas the clustered cardiometabolic risk score (cMetS) was calculated by summing z-scores of triglycerides, total cholesterol/HDL-C ratio, systolic blood pressure, glucose, and WC. Considering the combination of CRF (fitness) and WC (fatness), the following phenotypes were created: Fit/Unfat, Fit/Fat, Unfit/Unfat and Unfit/Fat. Moderation analyses were tested using linear regression models. Significant interactions were found between PA and Unfit/Fat category (ß = -0.001; p = 0.001) only for adolescents. The interaction observed in the Unfit/Fat phenotype indicated that adolescents who practise PA for 330 minutes per week presented lower cMetS compared to those who do not practise or practise for 60 minutes respectively. The combination of fitness and fatness moderates the relationship between PA and cardiometabolic risk, suggesting that adolescents, particularly those who are less fit and present high adiposity, should be encouraged to engage in regular PA to improve their metabolic health.

Cardiorespiratory fitness, screen time and cardiometabolic risk in South Brazilian school children.

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.

Choose Where You Live Carefully: Built Environment Differences in Children's Cardiorespiratory Fitness and Cardiometabolic Risk.

Information regarding urban-rural differences in health indicators are scarce in Brazil. This study sought to identify rural-urban differences in cardiorespiratory fitness (CRF) and cardiometabolic risk (CMR) in Brazilian children and adolescents whilst controlling for the important confounding variables including social economic status (SES). This is a cross-sectional study developed with children and adolescents (n = 2250, age 11.54 ± 2.76) selected from a city in the south of Brazil. CRF was estimated using a 6-minute run/walk test. CMR scores were calculated by summing different cardiometabolic risk indicators. CRF was analysed assuming a multiplicative model with allometric body-size components. CMR differences in residential locations was assessed using Analysis of caovariance (ANCOVA) adopting SES, Body Mass Index (BMI), waist circumference (WC), age and fitness as covariates. Results indicated a main effect of location (p < 0.001) with children living a rural environment having the highest CRF, and children living in the periphery of towns having the lowest. Analysis also revealed significant main effects of location (p < 0.001) with children living a rural environment having the lowest CMR and children living in the centre of towns having the highest. Therefore, Brazilian children living in a rural environment appear to have superior health benefits.

Association between cardiorespiratory fitness and cardiometabolic risk factors in Brazilian children and adolescents: the mediating role of obesity parameters.

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.

Cardiorespiratory Fitness and Muscular Strength Moderates the Relationship between FNDC5 Polymorphism and Adiposity in Children and Adolescents.

The human locus FNDC5 rs16835198 contributes positively to anthropometric phenotypes in children and adolescents. However, the role of specific components of physical fitness in this relationship is not known. The present study aimed to verify the moderator role of cardiorespiratory fitness (CRF) and muscular strength in the relationship between rs16835198 polymorphism FNDC5 and adiposity in children and adolescents. This cross-sectional study was carried out by genotyping the rs16835198 FNDC5 polymorphism in 1701 children and adolescents (mean age 11.73 ± 2.75 years). Obesity was assessed using waist circumference and body mass index (BMI) z-scores. To evaluate CRF and muscular strength, the 6 min run/walk test and lower limb strength (LLS) were used. Linear regression models were applied, and all analyses were adjusted for age, sex, skin color, living area, and school type. A significant interaction term for CRF (p = 0.038) and LLS (p = 0.040) × rs16835198 FNDC5 with WC was identified. Regarding BMI, a significant interaction term for CRF (p = 0.007) and LLS (p = 0.044) × rs16835198 FNDC5 was observed. Moreover, medium and high CRF and LLS levels protected against higher WC and BMI. In conclusion, adiposity levels of children and adolescents with a genetic predisposition to obesity might be modified by improving CRF and muscular strength.

A narrative review associating health vulnerability and environmental factors among rural workers.

BACKGROUND: Rural Brazil is known for its history of poor working and living conditions; in some regions the population becomes vulnerable to health and work problems. OBJECTIVE: To investigate the association between health vulnerability and environmental factors among rural workers. METHOD: Descriptive study which consisted in a narrative review of literature published from 2012 to 2017. The literature search was conducted in databases Scientific Electronic Library Online (SciELO) and Latin American and Caribbean Health Sciences Literature (LILACS) using Health Sciences Descriptors (DeCS) "health," "vulnerability," "rural population" and "rural worker health." RESULTS: Six studies were retrieved which mainly associated health vulnerability to inadequate or no use of specifically required personal protective equipment, in addition to pointing out actions essential for health promotion, such as adequate diet and leisure time, physical activity, dignified working conditions, and social contacts. CONCLUSION: Rural work environmental factors are directly related with health vulnerability. Prevention of exposure to risk of disease and health promotion actions are essential to minimize health problems, especially the ones associated with exposure to agrochemicals.

INTRODUÇÃO: O Brasil rural é conhecido historicamente pelas condições de trabalho e de vida precárias; em algumas regiões, essa população torna-se vulnerável às condições de saúde e trabalho. OBJETIVO: Descrever a associação entre a vulnerabilidade à saúde e os fatores ambientais em trabalhadores rurais. MÉTODO: Estudo de caráter descritivo caracterizado como revisão narrativa de literatura, no período de 2012 a 2017. Foram utilizadas as bases de dados Scientific Electronic Library Online (SciELO) e Literatura Latino-Americana e do Caribe em Ciências de Saúde (LILACS) e os Descritores em Ciências da Saúde (DECs) "saúde", "vulnerabilidade", "população rural" e "saúde do trabalhador rural". RESULTADOS: A pesquisa resultou em seis artigos que evidenciaram, principalmente, a vulnerabilidade à saúde relacionada com a utilização inadequada dos equipamentos de proteção individual específicos ao trabalho, ou a sua não utilização; além de apontar ações essenciais para a saúde, como manter uma alimentação adequada, ter momentos de lazer, praticar atividade física, ter condições dignas de trabalho e contato com grupos sociais. CONCLUSÃO: Conclui-se que os fatores ambientais no trabalho rural estão diretamente interligados com a vulnerabilidade à saúde, em que práticas de prevenção na exposição ao risco de doenças e de promoção à saúde são essenciais para minimizar os agravos à saúde, principalmente quanto à exposição de agrotóxicos em trabalhadores rurais.

High urate concentration is associated with elevated blood pressure in schoolchildren.

Background Studies in adults have shown a relationship between high blood pressure and hyperuricemia, but few studies have investigated this association in children and adolescents. The aim of the present study was to associate urate concentration with systolic blood pressure (SBP) and diastolic blood pressure (DBP) in schoolchildren. Methods This cross-sectional study used a sample of 2335 schoolchildren in basic education between 7 and 17 years old. Blood pressure was classified by percentile according to Brazilian parameters for sex and age, reclassified into two categories: normal and borderline/hypertension. Blood collection to obtain serum for urate concentration analysis was performed after a 12-h fast. Values above 5.5 mg/dL were considered hyperuricemia. Descriptive data were presented in frequency and percentage. Linear regression and Poisson regression (prevalence ratio [PR]) was used to test the association between urate concentration and blood pressure. Results Urate concentration was weakly associated with SBP (ß: 0.05; 95% CI: 0.02-0.08) and DBP (ß: 0.03; 95% CI: 0.01-0.05) z-scores. Schoolchildren with hyperuricemia had a higher prevalence of high SBP (PR: 1.12; p<0.001) and DBP (PR: 1.08; p<0.001). Conclusions Elevated urate concentration is associated with altered blood pressure in schoolchildren.