Camila Buonani

Modifiable risk factors for overweight and obesity in children and adolescents from São Paulo, Brazil.

BackgroundBrazil is currently experiencing a nutrition transition: the displacement of traditional diets with foods high in saturated fat, sodium, and cholesterol and an increase in sedentary lifestyles. Despite these trends, our understanding of child obesity in Brazil is limited. Thus, the aims of this study were (1) to investigate the current prevalence of overweight and obesity in a large sample of children and adolescents living in São Paulo, Brazil, and (2) to identify the lifestyle behaviors associated with an increased risk of obesity in young Brazilians.MethodsA total of 3,397 children and adolescents (1,596 male) aged 7-18 years were randomly selected from 22 schools in São Paulo, Brazil. Participants were classified as normal weight, overweight, or obese based on international age- and sex-specific body mass index thresholds. Selected sociodemographic, physical activity, and nutrition behaviors were assessed via questionnaire.ResultsOverall, 19.4% of boys and 16.1% of girls were overweight while 8.9% and 4.3% were obese. Two-way analysis of variance revealed that the prevalence of overweight and obesity was significantly higher in boys and in younger children when compared to girls and older children, respectively (P < 0.05 for both). Logistic regression analysis revealed that overweight was associated with more computer usage, parental encouragement to be active, and light soft drink consumption after controlling for differences in sex, age, and parental education (P < 0.05 for all). Conversely, overweight was associated with less active transport to school, eating before sleep, and consumption of breakfast, full-sugar soft drinks, fried food and confectionery (P < 0.05 for all).ConclusionsOur results show that obesity in São Paulo children and adolescents has reached a level equivalent to that seen in many developed countries. We have also identified three key modifiable factors related to obesity that may be appropriate targets for future intervention in Brazilian youth: transport mode to school, computer usage, and breakfast consumption.

The use of bioelectrical impedance to detect excess visceral and subcutaneous fat

OBJECTIVE To analyze bioelectrical impedance performance in detecting the presence of excess visceral fat and overweight/obesity in young Brazilians and how its values are related with them. METHODS Study sample consisted of 811 adolescents of both genders (11 to 17 years of age). Nutritional status was determined based on triceps skinfold thickness (TSF), relative body fat (bioelectrical impedance), and excess visceral fat as determined by waist circumference. Statistical analysis was performed using means, standard deviations, linear correlation, Students t test, and ROC curve. RESULTS Bioelectrical impedance achieved good performance in identifying excess visceral fat associated with overweight/obesity in both genders, and was found to be more specific (male 92.4% and female 93.8%) than sensitive (male 86.1% and female 71.8%). CONCLUSION Our findings support the use of bioelectrical impedance to identify the presence of excess visceral and subcutaneous fat in adolescents.

Performance of body fat and body mass index cutoffs in elevated blood pressure screening among male children and adolescents

For percentage of body fat (%BF), there are no internationally accepted cutoffs. The primary function of body fat cutoffs should be to identify not only excessive body fatness, but also the increased risk of unhealthy outcomes, such as hypertension. The purpose of this study was to analyze the accuracy of different %BF and body mass index (BMI) cutoffs as screening measures for EBP in pediatric populations. It was a cross-sectional study with a sample of 358 male subjects from 8 to 18 years old. BP was measured by the oscilometric method, and body composition was measured by dual-energy X-ray absorptiometry (DXA). The accuracy of three reference tables used for body fat cutoffs was assessed. The three body fat reference tables were highly specific, but insensitive, for elevated BP screening. For elevated BP screening, all body fat cutoffs presented similar sensitivity (range=48.3–53.7%) and specificity (range=79.2–84.1%). The body fat cutoffs performed no better than BMI in screening of children and adolescents at risk of elevated BP (EBP). BMI seems a more attractive tool for this function, as it performed similarly and can be applied in large surveys and with lower costs.

Combined Training (Aerobic Plus Strength) Potentiates a Reduction in Body Fat but Demonstrates No Difference on the Lipid Profile in Postmenopausal Women When Compared With Aerobic Training With a Similar Training Load

Abstract Rossi, FE, Fortaleza, ACS, Neves, LM, Buonani, C, Picolo, MR, Diniz, TA, Kalva-Filho, CA, Papoti, M, Lira, FS, and Freitas Junior, IF. Combined training (aerobic plus strength) potentiates a reduction in body fat but demonstrates no difference on the lipid profile in postmenopausal women when compared with aerobic training with a similar training load. J Strength Cond Res 30(1): 226–234, 2016—The aim of this study was to verify the effects of aerobic and combined training on the body composition and lipid profile of obese postmenopausal women and to analyze which of these models is more effective after equalizing the training load. Sixty-five postmenopausal women (age = 61.0 ± 6.3 years) were divided into 3 groups: aerobic training (AT, n = 15), combined training (CT [strength + aerobic], n = 32), and control group (CG, n = 18). Their body composition upper body fat (TF), fat mass (FM), percentage of FM, and fat-free mass (FFM) were estimated by dual-energy x-ray absorptiometry. The lipid profile, total cholesterol, high-density lipoprotein (HDL) cholesterol, and low-density lipoprotein cholesterol were assessed. There was a statistically significant difference in the TF (AT = −4.4%, CT = −4.4%, and CG = 1.0%, p = 0.001) and FFM (AT = 1.7%, CT = 2.6%, and CG = −1.4%, p = 0.0001) between the experimental and the control groups. Regarding the percentage of body fat, there was a statistically significant difference only between the CT and CG groups (AT = −2.8%, CT = −3.9%, and CG = 0.31%; p = 0.004). When training loads were equalized, the aerobic and combined training decreased core fat and increased FFM, but only the combined training potentiated a reduction in percentage of body fat in obese postmenopausal women after the training program. High-density lipoprotein-c levels increased in the combined group, and the chol/HDL ratio (atherogenic index) decreased in the aerobic group; however, there were no significant differences between the intervention programs. Taken together, both the exercise training programs were effective for improving body composition and inducing an antiatherogenic status.

Proposta de pontos de corte para indicação da obesidade abdominal entre adolescentes

BACKGROUND The absence of critical values for the cardiovascular risk identification among Brazilian adolescents represents an important limitation. OBJECTIVES To prepare critical values for the waist circumference and to analyze its efficiency in indicating increased values of the arterial pressure. METHODS Transversal study that evaluated 1,145 adolescents, from 11 to 17 years old (536 of the male sex and 609 of the female), their body weight values, stature, resistance, reactance, tricipital cutaneous fold, waist circumference and arterial pressure (n = 334) were collected. The abdominal obesity was indicated by waist circumference values. RESULTS The obese adolescents presented higher waist circumference values and, independently of the gender and age group, there was a significant relation between the waist circumference values and all the adiposity indicators adopted in the study. The proposed critical values presented higher sensibility in indicating increased values of the arterial pressure. CONCLUSIONS The critical values proposed for the waist circumference were more sensitive in the indication of increased values of the blood pressure. However, other studies to investigate their efficacy in the indication of other clinical and laboratorial parameters are still needed.FUNDAMENTO: A ausencia de valores criticos para a identificacao de risco cardiovascular entre adolescentes brasileiros representa uma importante limitacao. OBJETIVOS: Elaborar valores criticos para circunferencia de cintura e analisar sua eficiencia na indicacao de valores elevados de pressao arterial. METODOS: Estudo transversal que avaliou 1.145 adolescentes de 11 a 17 anos (536 do sexo masculino e 609 do feminino), dos quais foram coletados valores de peso corporal, estatura, resistencia, reatância, dobra cutânea tricepital, circunferencia de cintura e pressao arterial (n= 334). A obesidade abdominal foi indicada por meio de valores de circunferencia de cintura. RESULTADOS: Os adolescentes obesos apresentaram valores mais altos de circunferencia de cintura e, independentemente de genero e grupo etario, houve relacao significativa entre os valores de circunferencia de cintura e todos os indicadores de adiposidade adotados no estudo. Os valores criticos propostos apresentaram maior sensibilidade na indicacao de valores elevados de pressao arterial. CONCLUSOES: Os valores criticos propostos para circunferencia de cintura foram mais sensiveis na indicacao de valores elevados de pressao arterial. Entretanto, ainda sao necessarios estudos para averiguar a eficiencia dos mesmos na indicacao de outros parâmetros clinicos e laboratoriais.

Metabolic Syndrome: Criteria for Diagnosing in Children and Adolescents

Metabolic Syndrome (MS) is defined as a group of risk factors related to insulin resistance and its highest prevalence is found in obese individuals. The first observations concerning MS occurred in the 1920s, contributing to a surge of new associations between hyperglycemia and obesity. As of 1979, there was a greater understanding of one of its components: insulin resistance. The prevalence of MS varies according to the diagnostic criterion used, mainly for children and adolescents among which its prevalence has increased considerably. The principle criteria used in diagnosing the pediatric population are the International Diabetes Federation (IDF), National Cholesterol Education Program and Adult Treatment Panel III (NCEP-ATP III), World Health Organization (WHO) and I Prevention Directive against Atherosclerosis in Infancy and Adolescence, and due to their differences, the prevalence of the syndrome varies according to the diagnostic criterion used. Nevertheless, many points should be taken into consideration in choosing a criterion, such as sample size, age, applicability, risk factors to be considered and available resources. In this context, efficiency and applicability are advantages in distinct criteria.

Prevenção da síndrome metabólica em crianças obesas: uma proposta de intervenção

Objective: To analyze the effects of a 12-week intervention program based on physical activity practice, alimentary and psychological orientation on the risk factors for the development of metabolic syndrome in obese children and adolescents. Methods: A longitudinal study was conducted with 23 obese children and adolescents, aged six to 16 years (12.0±3.2 years). Total body and trunk fat mass, glycemia, total cholesterol, triglycerides, systolic and diastolic blood pressure were measured. The children were submitted to physical activity three times a week during 12 weeks. Each session of 60 minutes consisted of recreational sports activi- ties, gymnastics, circuits and track-walking. Chi-square test was used to compare categorical data for those patients who had values above the recommendations for each risk factor and Students t-test for paired data was used to compare the two moments of the study. Results: In subjects who had altered baseline values in the beginning of the study, the glycemia levels decreased 11.6% (from 105 to 93mg/dL; p=0.046) and the triglyc- erides decreased 24.9% (from 217 to 163mg/dL; p=0.013) after the intervention. On the other hand, no differences were noted for blood pressure and total cholesterol after the intervention. Conclusions: The intervention was effective in improv- ing blood glucose and triglycerides levels in children and adolescents enrolled in the study.

Effect of combined aerobic and resistance training in body composition of obese postmenopausal women

Abstract —The aim of this study was to investigate the effects of a 16-week program of combined aerobic and resistance training on the body composition of postmenopausal women who are obese. The participants were divided into two groups: training group (TG, n = 37) and non-trained control group (CG, n = 18). The trunk fat, fat mass, percentage of fat mass and fat-free mass were estimated using DXA. Threenonconsecutive 24-hour dietary recalls were conducted. The training protocol consisted of 50 minutes of resistance training followed by 30 minutes of aerobic training. After the 16-week training program, differences were observed in trunk fat (CG= 0.064 x TG= -0.571 Kg; p -value = .020), fat mass (CG= -0.088 x TG= -1.037 Kg; p -value = .020) and fat-free mass (CG= -0.388 x TG= 1.049 Kg; p = .001). Therefore, a 16-week program of systematic combined aerobic and resistance training in obese postmenopausal women was effective in improving fat-free mass and decreasing both whole and abdominal adiposity. Keywords: obesity, endurance training, DXA, climacteric

Relationship between moderate-to-vigorous physical activity, abdominal fat and immunometabolic markers in postmenopausal women.

OBJECTS To assess the burden of levels of physical activity, non-esterified fatty acids (NEFA), triacylglycerol and abdominal fat on the immunometabolic profile of postmenopausal women. STUDY DESIGN Forty-nine postmenopausal women [mean age 59.43 (standard deviation 5.61) years] who did not undertake regular physical exercise participated in this study. Body composition was assessed using dual-energy X-ray absorptiometry, and levels of NEFA, tumour necrosis factor-α, adiponectin, insulin and triacylglycerol were assessed using fasting blood samples. The level of physical activity was assessed using an accelerometer (Actigraph GTX3x), and reported as counts/min, time spent undertaking sedentary activities and time spent undertaking moderate-to-vigorous physical activity (MVPA). The following conditions were considered to be risk factors: (i) sedentary lifestyle (<150min of MVPA per week); (ii) high level (above median) of abdominal fat; and (iii) hypertriacylglycerolaemia (<150mg/dl of triacylglycerol). RESULTS In comparison with active women, sedentary women had higher levels of body fat (%) (p=0.041) and NEFA (p=0.064). Women with higher levels of abdominal fat had impaired insulin resistance (HOMA-IR) (p=0.016) and spent more time undertaking sedentary activities (p=0.043). Moreover, the women with two risk factors or more had high levels of NEFA and HOMA-IR (p<0.05), as well as an eight-fold higher risk of a high level of NEFA, independent of age (p<0.05). No significant relationship was found between levels of physical activity, abdominal fat, tumour necrosis factor-α and adiponectin (p>0.05). CONCLUSION Postmenopausal women with a combination of hypertriacylglycerolaemia, a high level of abdominal fat and a sedentary lifestyle are more likely to have metabolic disturbances.

Gordura corporal total e do tronco e o desempenho da marcha em mulheres na menopausa

OBJETIVO: Verificar a relacao entre gordura corporal total e de tronco com o desempenho da marcha em mulheres na menopausa.METODOS: Trinta e nove mulheres na menopausa, com idade de 50 anos ou mais, foram avaliadas. As avaliacoes foram: peso e estatura para calculo do indice de massa corporal (IMC), composicao corporal pela tecnica de Dual-Energy X-ray Absorptiometry (DEXA) e marcha utilizando um baropodometro. As variaveis de composicao corporal utilizadas foram gordura corporal total, percentual de gordura corporal e gordura de tronco, enquanto as variaveis da marcha foram porcentagem de tempo de duplo apoio e de apoio simples e velocidade. As mulheres foram divididas de acordo com a mediana em dois grupos para cada variavel da composicao corporal: menos e mais gordura corporal, menos e mais percentual de gordura e menos e mais gordura de tronco. Para comparar as variaveis de marcha nesses grupos, foi utilizado o teste de Mann-Whitney. Para avaliar as possiveis relacoes entre as variaveis de composicao corporal e marcha, o teste de correlacao de Spearman foi utilizado. Todas as analises foram realizadas com nivel de significância de 5%.RESULTADOS: O grupo com mais gordura de tronco, quando comparado com o grupo com menos gordura de tronco, apresentou maiores valores de duplo apoio (p=0,007) e menores valores de apoio simples (0,03). Foram encontradas correlacoes significativas e positivas entre gordura de tronco e duplo apoio (R=0,40) e negativas entre gordura de tronco e apoio simples (R=-0,32).CONCLUSAO: Mulheres na menopausa que apresentam maiores quantidade de gordura no tronco tendem a apresentar desempenho prejudicado na marcha.