Luciana Carletti

Cardiovascular risk factors, their associations and presence of metabolic syndrome in adolescents

OBJECTIVE To evaluate the occurrence of metabolic syndrome (MS) and independent associated risk factors in adolescents in the city of Vitória, Brazil. METHODS We assessed 380 adolescents aged 10 to 14 years attending public schools. Body mass index and blood pressure at rest were measured. Fasting plasma concentrations of total cholesterol, LDL-cholesterol, HDL-cholesterol, triglycerides and glucose were also obtained. RESULTS The prevalence of overweight was 9.6% for boys and 7.4% for girls, while obesity was found in 6.2 and 4.9%, respectively. Triglyceride concentrations were borderline or high in 6.8 and 3.4% of the boys and in 11.8 and 5.9% of the girls. HDL-cholesterol was below recommended levels in 8.5% of the boys and in 9.9% of the girls. Blood pressure at rest was borderline for 5.1% of the boys and 7.9% of the girls, while 3.4% of both boys and girls were hypertensive. Fasting glycemia was high in 0.6% of the boys and in 0.5% of the girls. In the group studied, 2.8% of the boys and 2.5% of the girls had two risk factors associated with MS. Prevalence of MS was 1.1% for boys and 1.5% for girls, and overall prevalence was 1.3%. CONCLUSIONS MS and associated cardiovascular risk factors are serious clinical conditions in this age group. A significant number of adolescents showed borderline results, which may increase the prevalence of MS or independent risk factors in the short term. More investments should be made in primary prevention, considering that early diagnosis is an issue of fundamental importance.

Maximum oxygen uptake in adolescents as measured by cardiopulmonary exercise testing: a classification proposal

OBJECTIVE The identification of populational levels of maximum oxygen uptake (VO(2max)) is an aid to studies that propose to relate physical fitness to cardiovascular risk, and also for prescribing exercise and analyzing the effects of training. To date, there is no information with which this parameter can be classified in samples of adolescents from the Brazilian population. This study is, therefore, the first to propose the determination of mean VO(2max) levels in a sample of the Brazilian population. METHODS A sample of 380 schoolchildren (177 boys and 203 girls, aged 10 to 14 years) was selected at random from public schools in Vitória, ES. After anthropometric assessment they underwent cardiopulmonary exercise testing, VO(2max) was measured directly and results were classified according to quintiles calculated from the study sample. RESULTS The mean VO(2max) values observed ranged from 42.95 to 49.55 mL x kg(-1) x min(-1) for boys and from 36.76 to 38.29 mL x kg(-1) x min(-1) for girls. CONCLUSION This paper proposes mean VO(2max) ranges as a classification parameter for cardiorespiratory fitness, in addition to contributing to a definition of normal values for the Brazilian population. This classification will also be of use for establishing cutoff points in future studies.

Resposta da pressão arterial ao esforço em adolescentes: influência do sobrepeso e obesidade

BACKGROUND: The acute blood pressure response to physical exertion has been used as an indicator of the risk of developing hypertension. The factors associated with this response need to be clarified for timely intervention in preventing hypertensive disease. OBJECTIVE: To describe the response of cardiovascular variables to acute physical exertion in overweight adolescents using cardiopulmonary exercise testing. METHODS: The sample consisted of 104 adolescents (56 boys and 48 girls), divided into two groups: the obese/overweight group (OOG) and the eutrophic group (EG). The following variables were measured: anthropometric (weight, height, and BMI), body composition (skin fold thickness), as well as hemodynamic variables such as systolic arterial pressure (SAP), diastolic arterial pressure (DAP), and heart rate (HR), at rest and at maximal physical exertion during the cardiopulmonary test. RESULTS: In the male group, the greatest values of systolic arterial pressure at rest were recorded in the OOG as compared to the EG (113 ± 13 vs 106 ± 8 mmHg; p = 0.009), pre-exertion SAP (120 ± 14 vs 109 ± 10 mmHg; p = 0.003), and SAP during maximal exertion conditions (156 ± 20 vs 146 ± 14 mmHg; p = 0.03). In the female group, only pre-exertion SAP was higher in the overweight group as compared to the eutrophic girls (114 ± 11 vs 106 ± 10 mmHg; p = 0.009). CONCLUSION: The response of arterial blood pressure during physical exercise was most exacerbated in obese adolescents as compared to eutrophic teens, suggesting greater reactivity to physical exertion.

Valores de consumo máximo de oxigênio determinados pelo teste cardiopulmonar em adolescentes: uma proposta de classificação

OBJECTIVE: The identification of populational levels of maximum oxygen uptake (VO2max) is an aid to studies that propose to relate physical fitness to cardiovascular risk, and also for prescribing exercise and analyzing the effects of training. To date, there is no information with which this parameter can be classified in samples of adolescents from the Brazilian population. This study is, therefore, the first to propose the determination of mean VO2max levels in a sample of the Brazilian population. METHODS: A sample of 380 schoolchildren (177 boys and 203 girls, aged 10 to 14 years) was selected at random from public schools in Vitoria, ES. After anthropometric assessment they underwent cardiopulmonary exercise testing, VO2max was measured directly and results were classified according to quintiles calculated from the study sample. RESULTS: The mean VO2max values observed ranged from 42.95 to 49.55 mL.kg-1.min-1 for boys and from 36.76 to 38.29 mL.kg-1.min-1 for girls. CONCLUSIONS: This paper proposes mean VO2max ranges as a classification parameter for cardiorespiratory fitness, in addition to contributing to a definition of normal values for the Brazilian population. This classification will also be of use for establishing cutoff points in future studies.

Active and sedentary behaviours in children aged 7 to 10 years old: the urban and rural contexts, Brazil

BackgroundAlthough the effects of physical activity (PA) on health and wellness are well-established, incorporating sedentary behaviours in the daily lives of populations from high- and medium-income countries is becoming increasingly common. Regardless of other factors, the area of residence can influence the physical activity level and sedentary behaviours. The aim of this study was to identify and analyse active and sedentary behaviours and factors associated with physical activity in two different geographical areas in south-eastern Brazil.Methods1.770 schoolchildren aged 7-10 years old were studied. Parents or caregivers completed a validated questionnaire on PA and sedentary behaviours. Screen time (ST) was calculated from the time spent watching television, playing video games and using the computer. The level of active PA (>300 minutes per week) was identified and compared between the areas of study. Parametric and non-parametric tests and Poisson regression model with robust variance were used for statistical analysis.ResultsCompared to schoolchildren from the urban area, those from the rural area showed a higher percentage of compliance with the PA recommendations (87 vs. 69.7%) and screen time <2 h (34.8 vs. 18.8%) and less participation in supervised PA. Active commuting to school was more common among schoolchildren from urban areas, although using a bicycle was more common in rural areas. The characteristics of children who do not meet the recommended weekly PA are as follows: being female, living in urban areas, being overweight, not using video games or performing supervised PA. Total ST as well as daily use of television and the computer was not associated with physical activity level in the present sample. Participation in supervised physical activities in both areas was found to increase the prevalence of being active in the areas studied.ConclusionsThe results of the present study suggest that while schoolchildren from rural areas are more active and spend less time on sedentary activities than those from the urban area, the time spent in sedentary behaviors, such as watching television, playing video games and using the computer, is high in both contexts, and it is not associated with physical activity recommendation compliance.

Long-term intense resistance training in men is associated with preserved cardiac structure/function, decreased aortic stiffness, and lower central augmentation pressure.

Objective: There have been contradictory reports regarding resistance exercise and central arterial compliance. The American Heart Association has recommended its use in preventing/treating cardiovascular diseases. We examined the effects of long-term endurance running and intense resistance training on central hemodynamics, compared with healthy control (CON). Methods: Sixty-nine male participants, 25–50 years [19 intense resistance trained (IRT) group, 21 endurance runners, and 29 CON] were investigated by radial tonometry-pulse wave analysis, pulse wave velocity (PWV), and echocardiogram. Data were expressed as mean ± SE (median). Differences were tested by analysis of variance and analysis of covariance was used to adjust for confounding variables. Results: There were no differences among groups regarding age, height (Ht), brachial and central blood pressure. Resting heart rate (HR) was lower and high-density lipoprotein cholesterol (HDL-C) higher in endurance runners. Weight, peripheral pulse pressure, and pulse pressure amplification were higher and HDL-C lower in the IRT group. Left ventricular mass and creatine phosphokinase were higher in trained participants. Relative wall thickness was similar among groups. The ratio of the velocity of peak E and A waves (E/A) was higher and PWV significantly lower in endurance runners (7.2 ± 0.14 m/s) and IRT (7.5 ± 0.14 m/s) as compared with CON (8.2 ± 0.16 m/s) even after adjustments for age, Ht, HR and mean arterial pressure (MAP), or mean systolic pressure. Differences in central augmentation pressure (cAP) adjusted for age, height, systolic or MAP, PWV, and HR (IRT equal to 0.08 ± 0.9, CON equal to 3.4 ± 0.9 and endurance running equal to 3.6 ± 1) were no longer significant after further adjustments to aortic diameter or weight. Conclusion: Long-term resistance training in men is associated with preserved cardiac structure/function, decreased aortic stiffness, and lower cAP.

Heart rate at 4 s after the onset of exercise in endurance-trained men

It has been suggested that the increase in heart rate (HR) at the onset of exercise is caused by vagal withdrawal. In fact, endurance runners show a lower HR in maximum aerobic tests. However, it is still unknown whether endurance runners have a lower HR at 4 s after the onset of exercise (4th-sec-HR). We sought to measure the HR at the onset of the 4 s exercise test (4-sET), clarifying its relationship to heart rate variability (HRV), spectral indices, and cardiac vagal index (CVI) in endurance runners (ER) and healthy untrained controls (CON). HR at 4th-sec-HR, CVI, and percent HR increase during exercise were analyzed in the 4-sET. High frequency spectrum (HF-nu), low frequency spectrum (LF-nu), and low frequency/high frequency band ratio (LF/HF) were analyzed from the HRV. ER showed a significantly higher HF, and both a lower LF and LF/HF ratio compared with the CON. ER presented a significantly lower 4th-sec-HR, although neither CVI nor HR increases during exercise were statistically different from the CON. In conclusion, ER presented a lower 4th-sec-HR secondary to increased vagal influence over the sinus node. CVI seems to be too weak to use for discriminating individuals with respect to the magnitude of HR vagal control.

Desempenho em teste cardiopulmonar de adolescentes: peso normal e excesso de peso

INTRODUCAO: Sabe-se que o excesso de peso interfere no desempenho fisico do cotidiano do adolescente e, consequentemente, na aptidao fisica e na capacidade cardiorrespiratoria.OBJETIVO: O estudo objetivou identificar e comparar os valores das variaveis cardiorrespiratorias no limiar anaerobico ventilatorio (LAV) de adolescentes com peso normal e excesso de peso.METODOS: A amostra foi composta por 140 adolescentes de ambos os sexos entre 10 e 14 anos, escolares do municipio de Vitoria, ES, Brasil. Foram mensuradas massa corporal e estatura para calculo do indice de massa corporal (IMC). Os adolescentes foram divididos em grupo peso normal (GPN) e grupo excesso de peso (GEP), realizaram um eletrocardiograma de repouso e um teste cardiopulmonar de exercicio em esteira ergometrica (Inbrasport Super ATL) utilizando o ergoespirometro MedGraphics Corporation e o protocolo de rampa. O LAV foi identificado pelo metodo V-slope e/ou equivalente ventilatorio de oxigenio (VE/VO2). Foram analisadas as seguintes variaveis no LAV: consumo de oxigenio (VO2LAV ml.kg-1.min-1), frequencia cardiaca (FCLAV bpm), percentuais do consumo maximo de oxigenio (%VO2maxLAV) e da FC maxima (%FCmaxLAV), e velocidade (VelLAV km/h), alem do consumo maximo de oxigenio (VO2maxml.kg-1.min-1) e FC maxima (FCmax). Foi realizado teste t de Studentnas comparacoes entre os grupos, considerando p<0,05 para significância estatistica.RESULTADOS: O GPN apresentou valores significativamente maiores no LAV para VO2ml.kg-1.min-1 (20,0 ±6,4 vs 15,8 ±5,7) e velocidade (7,1 ±0,9km/h vs 6,2 ±1,1km/h), e para o VO2max (44,6 ±7,6 vs 36,0 ±6,4) quando comparado ao GEP.CONCLUSAO: Os dados sugerem que adolescentes com excesso de peso apresentam prejuizo na aptidao cardiorrespiratoria nao somente ao nivel maximo, mas tambem ao nivel submaximo (LAV) quando comparados aos adolescentes com peso normal.Introduction: It is known that excess weight interferes with the daily physical performance of adolescents and consequently, in physical adaptation and cardiorespiratory capacity. Objective: The study aimed to identify and compare the cardiorespiratory variables at the ventilatory anaerobic threshold (VAT) of normal weight and overweight adolescents. Methods: The sample consisted of 140 adolescent students of both sexes, aged between 10 and 14 years, in the city of Vitoria, ES. Body weight and height were measured, to calculate the body mass index (BMI). The adolescents were divided into normal weight group (NWG) and overweight group (OWG). A resting electrocardiogram was performed, and a cardiopulmonary exercise test on a treadmill (Inbrasport Super ATL) using a MedGraphics Corporation ergospirometer and the ramp protocol. The VAT was identified by the V-slope method and/or ventilatory equivalent of oxygen (VE/VO2). The following variables were analyzed in the VAT: oxygen consumption (VO(2VAT)ml.kg(-1).min(-1)), heart rate (bpm HRVAT), percentages of maximum oxygen uptake (%VO2maxVAT) and maximum HR (%HRmaxVAT) and speed (Vel(VAT) km/h), as well as maximum oxygen uptake (VO2max ml.kg(-1).min(-1)) and maximum heart rate (HRmax). The Students T-test was performed for comparisons between groups, considering p < 0.05 for statistical significance. Results: The NWG was significantly higher in VAT for VO2 ml.kg(-1).min(-1) (20.0 +/- 6.4 vs 15.8 +/- 5.7) and speed (7.1 +/- 0.9 km/h vs 6.2 +/- 1.1 km/h), and VO2max (44.6 +/- 7.6 vs. 36.0 +/- 6.4) compared to the OWG. Conclusion: The data suggest that overweight adolescents have impaired cardiorespiratory fitness not only at the maximum level, but also at submaximal level (VAT), compared with normal weight adolescents.

Comparação da resposta autonômica cardiovascular de praticantes de musculação, corredores de longa distância e não praticantes de exercício

The aim of the study was to compare the cardiovascular autonomic response (CAR) of recreational weight trainers, long distance runners and non-exercised subjects. Men, 21 to 55 years old, were grouped in: recreational weight trainers (W, n = 31), long distance runners (R, n = 28) and non-exercised (C, n = 35). Four strategies of evaluation of the CAR were selected: Resting heart rate (RHR), cold pressor test (CPT), heart rate variability (HRV) and heart rate recovery (HHR) following maximal exercise test. The RHR was lower (R = 54 ± 2; W = 62 ± 2; C= 65 ± 2 bpm; mean ± SE) and the HHR 60s post exercise was larger in the R group (R = 34 ± 3; W = 23 ± 1; C = 24 ± 2 bpm). The R group presented larger high-frequency (HF; 55.1 ± 4.0 n.u) and smaller low-frequency (LF; 43.1 ± 4.0 n.u) components of HRV than C group (HF = 40.7 ± 3.3; LF = 56.7 ± 3.5 n.u.). The W group did not show any differences compared to C group. The studys conclusion was that long-term weight-training program, unlike of long-term running training, it is not able to alter significantly the regulatory pattern of CAR.

Reprodutibilidade do questionário de avaliação de atividade física para crianças aplicado no Estudo Saúdes: Vitória

Objectives: to evaluate the reproducibility of a physical activity assessment questionnaire for children aged between 7 and 10 years among participants of the Saudes Vitoria Study in Espirito Santo State, Brazil. Methods: a cross-sectional study was carried out in a random sample of 91 children enrolled in public and private sector schools in the municipality. A structured questionnaire with 13 questions was sent to the home of selected children, to be filled out twice, with an interval of 15 days. To evaluate the reproducibility the Kappa agreement test was used for the