Aerobic training with a self-selected or predetermined intensity on sleep parameters in adolescents with obesity: a randomized clinical trial.

Objectives: To compare the effects of self-selected and predetermined intensity on sleep quality and duration, daytime sleepiness, and sleep efficiency of adolescents with obesity after 12 weeks of aerobic training. Material and Methods: Thirty-seven adolescents (12 girls), 13-18 years old, with obesity (BMI = 95th) were randomized into a predetermined intensity group (PIG), exercise intensity around 60-70% of heart rate reserve; or self-selected intensity group (SIG), the adolescents chose the speed/intensity at the beginning of each session and were able to change it every 5 minutes. The Pittsburgh Sleep Quality Index (PSQI) and Epworth Sleepiness Scale (ESS) were used to assess sleep outcomes. Results: No differences were observed for PSQI [0.00 ± 2.00 vs 1.38 ± 2.7; p=0.195; d=0.60 (moderate effect)], sleep duration [-0.95 ± 1.2 vs -0.35 ± 1.6; p=0.358; d=0.41 (small effect)], ESS [(2.10 ± 3.9 vs 1.15 ± 4.5; p=0.195; d=0.23 (small effect)], and sleep efficiency [(81.5 ± 24.0 vs 79.4 ± 17.0; p=0.8.14; d=0.10 (trivial effect)] for the PIG and SIG groups, respectively. Conclusion: Aerobic training at a self- selected or predetermined intensity does not modulate sleep quality, sleep duration and efficiency, and daytime sleepiness, independent of intensity.

Flexibility of Brazilian children and adolescents: a systematic review of the literature / Flexibilidade de crianças e adolescentes brasileiros: uma revisão sistemática da literatura

abstract Flexibility is related to specific tissue properties of the body, which aim to determine the maximum range of motion of the joints without injury. This study aimed to identify and summarize the evidence on prevalence of adequate levels of flexibility in Brazilian children and adolescents (6 to 19 years old). We performed a systematic search of studies published from 2009 to 2019 in six databases (MEDLINE/PubMed; Scopus; SportDiscus; LILACS; Web of Science; SCIELO). Fourteen studies that compiled data from 11,666 participants in seven different Brazilian states were included. All studies conducted sit and reach tests to assess flexibility. Among all the children and adolescents in the analyzed studies, 58.9% of the total (62.0% of boys and 50.9% of girls) had adequate flexibility. We conclude that more than half of Brazilian children and adolescents have adequate flexibility for health.

resumo A flexibilidade está relacionada com propriedades específicas teciduais que permitem a amplitude máxima de movimento articular sem a presença de lesão. O presente estudo teve como objetivo identificar e sintetizar as evidências sobre a prevalência de níveis adequados de flexibilidade em crianças e adolescentes brasileiros (6 a 19 anos). Foi realizada uma busca sistematizada de estudos publicados de 2009 a 2019 em seis bases de dados (MEDLINE/PubMed; Scopus; SportDiscus; LILACS; Web of Science; SCIELO). Foram incluídos 14 estudos que compilaram dados de 11.666 participantes em sete estados brasileiros diferentes. Todos os estudos realizaram teste de sentar e alcançar para avaliar a flexibilidade. Dentre todas as crianças e adolescentes dos estudos analisados, 58,9% do total (62,0% dos meninos e 50,9% das meninas) apresentaram flexibilidade adequada. Concluímos que mais da metade das crianças e adolescentes brasileiros possuem flexibilidade adequada para a saúde.

Aerobic training in obese adolescents: a multidisciplinary approach / Treinamento aeróbio em adolescentes obesos: uma abordagem multidisciplinar / Entrenamiento aeróbico en obesos adolescentes: un enfoque multidisciplinario

ABSTRACT Introduction: The prevalence of excess weight/obesity in adolescence has increased, and physical training may be effective in combating this scenario. Objective: To analyze the effect of different intensities of aerobic training on the body composition of obese adolescents undergoing multidisciplinary intervention. Methods: In this study, 107 pubertal (Tanner 3 and 4), obese (BMI=34.72±4.10 kg/m²) adolescents (14.85±1.44 years) were randomly assigned to three groups: high intensity training (HITG - ventilatory threshold I (VTI)); low intensity training (LITG - 20% below the VTI) and control group (CG), without intervention. The adolescents in the HITG and LITG underwent nutritional and psychological (1x/week) and clinical (1 x/month) follow-up and physical training (3x/week) for 12 weeks. Results: Reductions in fat mass (FM) and body fat percentage (BFP) (p< 0.001) and an increase in fat-free mass (FFM) (p<0.001) were observed in all groups. There was a reduction in BMI only in the experimental groups (p<0.001). Conclusion: The effects of multidisciplinary treatment on the body composition of obese adolescents occur independently of the intensity of aerobic physical training. Level of Evidence I; High quality randomized clinical studies with or without statistically significant difference, but with narrow confidence intervals.

RESUMO Introdução: A prevalência de sobrepeso / obesidade na adolescência aumentou, e treinamento físico pode ser eficaz para combater este cenário. Objetivo: Analisar o efeito de diferentes intensidades de treinamento aeróbio sobre a composição corporal de adolescentes obesos, submetidos à intervenção multidisciplinar. Métodos: Neste estudo, 107 adolescentes (14,85±1,44 anos), púberes (Tanner 3 e 4) e obesos (34,72±4,10 kg/m²) foram aleatoriamente alocados em três grupos: treinamento de alta intensidade (GTAI - limiar ventilatório I (LVI)), treinamento de baixa intensidade (GTBI - 20% abaixo do LVI) e grupo controle (GC), sem intervenção. Os adolescentes do GTAI e GTBI receberam acompanhamento nutricional e psicológico (1x/semana), clínico (1x/mês) e treinamento físico (3x/semana) durante 12 semanas. Resultados: Foram observadas reduções na massa gorda (MG) e no percentual de gordura (%G) em todos os grupos (p<0,001) e um aumento na massa livre de gordura (MLG) (p<0,001). Houve redução no IMC apenas nos grupos experimentais (p<0,001). Conclusão: Os efeitos do tratamento multidisciplinar sobre a composição corporal de adolescentes obesos ocorrem independentes da intensidade do treinamento físico aeróbio. Nível de Evidência I; Estudos clínicos randomizado de alta qualidade com ou sem diferença estatisticamente significante, mas com intervalos de confiança estreitos.

RESUMEN Introducción: La prevalencia de sobrepeso / obesidad en la adolescencia aumentó, y el entrenamiento físico puede ser eficaz para combatir este escenario. Objetivo: Analizar el efecto de diferentes intensidades de entrenamiento aeróbico sobre la composición corporal de adolescentes obesos sometidos a la intervención multidisciplinaria. Métodos: En este estudio, 107 adolescentes (14,85 ± 1,44 años), púberes (Tanner 3 y 4), obesos (34,72 ± 4,10 kg / m²) fueron aleatoriamente asignados en tres grupos: entrenamiento de alta intensidad (GEAI - umbral de ventilación I (LVI)); El entrenamiento de baja intensidad (GEBI - 20% por debajo del LVI) y el grupo de control (GC), sin intervención. Los adolescentes del GEAI y GEBI recibieron seguimiento nutricional y psicológico (1x/semana), clínico (1x/mes) y entrenamiento físico (3x/ semana) durante 12 semanas. Resultados: Se observaron reducciones en la masa grasa (MG) y en el porcentaje de grasa (% G) en todos los grupos (p<0,001) y un aumento en la masa libre de grasa (MLG) (p<0,001). Se observó una reducción en el IMC sólo en los grupos experimentales (p<0,001). Conclusión: Los efectos del tratamiento multidisciplinario sobre la composición corporal de adolescentes obesos ocurren independientes de la intensidad del entrenamiento físico aeróbico. Nivel de Evidencia I; Estudio clínico aleatorio de alta calidad, con o sin diferencia estadísticamente significativa, pero con estrechos intervalos de confianza.

Cardiorespiratory fitness in adolescents with obesity: a 6-month follow-up study / Aptidão Cardiorrespiratória em Adolescentes com obesidade: um estudo de seguimento de 6 meses

The aim of this study was to investigate whether the effects of a multidisciplinary intervention on cardiorespiratory fitness are maintained after 6-month follow-up in adolescents with obesity. One-hundred and seven adolescents with obe-sity were intentionally allocated in two groups: experimental or control. Adolescents in experimental group underwent a multidisciplinary intervention (supervised aerobic exercise, psychological, nutritional, and clinical counseling). Cardiorespiratory fitness (direct gas analysis), body composition (dual-energy-DXA), anthropometry and blood lipids were measured before intervention (baseline), at the end of the 24-week intervention (post-intervention) and six months after the end of the intervention (follow-up). Cardiorespiratory fitness reduced in control group with no changes in experimental group, and these differences were maintained in the follow-up assessment (control group: 24.2±4.4 ml.kg-1.min-1to 22.6±4.9 ml.kg-1.min-1; follow-up: 22.6±4.9 ml.kg-1.min-1 vs. experimental group: 28.0±4.0 ml.kg-1.min-1 to 29.7±4.0 ml.kg-1.min-1; follow-up: 28.9±5.7 ml.kg-1.min-1). Reductions in z-score body mass index (BMI) and increases HDL-C af-ter multidisciplinary intervention were maintained after a 6-month follow-up. In conclusion, the benefits of a multidisciplinary intervention on cardiorespiratory fitness, BMI and blood lipids are maintained after a 6-month follow-up. These findings indicate that multidisciplinary interventions produce long-term health consequences on cardiorespiratory fitness. Reinforcing the importance of lifestyle changes as a therapeutic approach for the treatment of obesity in adolescents.

O objetivo do presente estudo foi investigar se os efeitos da intervenção multidisciplinar sobre a aptidão cardiorrespiratória são mantidos após um período de segmento de 6 meses em adolescentes com obesidade. Cento e sete adolescentes com obesidade foram intencionalmente alocados em dois grupos: experimental e controle. Os adolescentes do grupo experimental foram submetidos a intervenção multidisciplinar composta por acompanhamento psicológico, nutricional, clínico e treinamento aeróbio. Aptidão cardiorrespiratória (análise de gases), composição corporal (DEXA), antropometria e perfil lipídico foram avaliados no momento basal, após 24 semanas de intervenção e 6 meses após (follow up). A aptidão cardiorrespiratória reduziu no grupo controle sem alterações no grupo experimental, mesmo após o período de 6 meses (controle: 24,2±4,4 ml.kg-1.min-1 para 22,6±4,9 ml.kg-1.min-1; follow-up: 22,6±4,9 ml.kg-1.min-1 vs. grupo experimental: 28,0±4,0 ml.kg-1.min-1 para 29.7±4.0 ml.kg-1.min-1; follow-up: 28,9±5,7 ml.kg-1.min-1). Redução no escore-z do índice de massa corporal (Z-IMC) e elevação do HDL-c verificadas após 24 semanas, foram mantidas após o período de segmento. Os resultados indicam que os efeitos da intervenção multidisciplinar são mantidos após 6 meses de seguimento. Estes achados sugerem que intervenções multidisciplinares podem produzir alterações benéficas de longo prazo na capacidade cardiorrespiratória.

Obstetric complications and mother's age at delivery are predictors of eating disorder symptoms among Health Science college students.

OBJECTIVE: To identify the association between perinatal/neonatal factors and symptoms of eating disorders among college students. METHODS: Four hundred and eight college students (283 women), aged 18 to 23 years old, enrolled in the first semester of a Bachelor of Health Science degree program were included in the sample. Eating disorder symptoms and body image dissatisfaction were assessed with the Eating Attitudes Test and Bulimic Investigatory Test of Edinburgh. Information regarding birth weight, breastfeeding, obstetric complications, mother's age at delivery, type of delivery, and birth order were self-reported by the volunteers after consulting their parents. Association between perinatal and neonatal factors and symptoms of anorexia nervosa and bulimia nervosa were assessed by binary logistic regression adjusted for sex, age, and body mass index. RESULTS: The likelihood of presenting with symptoms of anorexia nervosa was 0.5 time lower for those students born from the oldest mothers (odds ratio - OR=0.37; 95% confidence interval - 95%CI: 0.17-0.83). Relative to bulimia nervosa, the risk was higher among students who reported obstetric complications (OR=2.62; 95%CI: 1.03-6.67). CONCLUSION: We observed the association between perinatal and neonatal factors with symptoms of eating disorders in college students.

Obstetric complications and mother’s age at delivery are predictors of eating disorder symptoms among Health Science college students / Complicações obstétricas e idade materna no parto são preditores de sintomas de transtornos alimentares em estudantes universitários da área da Saúde

ABSTRACT Objective To identify the association between perinatal/neonatal factors and symptoms of eating disorders among college students. Methods Four hundred and eight college students (283 women), aged 18 to 23 years old, enrolled in the first semester of a Bachelor of Health Science degree program were included in the sample. Eating disorder symptoms and body image dissatisfaction were assessed with the Eating Attitudes Test and Bulimic Investigatory Test of Edinburgh. Information regarding birth weight, breastfeeding, obstetric complications, mother’s age at delivery, type of delivery, and birth order were self-reported by the volunteers after consulting their parents. Association between perinatal and neonatal factors and symptoms of anorexia nervosa and bulimia nervosa were assessed by binary logistic regression adjusted for sex, age, and body mass index. Results The likelihood of presenting with symptoms of anorexia nervosa was 0.5 time lower for those students born from the oldest mothers (odds ratio – OR=0.37; 95% confidence interval – 95%CI: 0.17-0.83). Relative to bulimia nervosa, the risk was higher among students who reported obstetric complications (OR=2.62; 95%CI: 1.03-6.67). Conclusion We observed the association between perinatal and neonatal factors with symptoms of eating disorders in college students.

RESUMO Objetivo Identificar a associação entre fatores perinatais/neonatais e sintomas de transtornos alimentares entre estudantes universitários. Métodos Quatrocentos e oito estudantes universitários (283 mulheres), com idade entre 18 e 23 anos, matriculados no primeiro semestre de cursos de Bacharelado na área das Ciências da Saúde foram incluídos na amostra. Sintomas de transtornos alimentares e de insatisfação com a imagem corporal foram avaliados por meio do Eating Attitudes Test e do Bulimic Investigatoty Test of Edinburgh. Informações sobre o peso ao nascer, aleitamento materno, complicações obstétricas, idade materna no momento do parto, tipo de parto e ordem de nascimento foram relatadas pelos voluntários após consulta com seus pais. A associação entre fatores perinatais/neonatais e sintomas de anorexia nervosa e bulimia nervosa foi avaliada por meio de regressão logística binária ajustada por sexo, idade e índice de massa corporal. Resultados A probabilidade de apresentar sintomas de anorexia nervosa foi 0,5 vez mais baixa para os alunos nascidos de mães mais velhas (odds ratio – OR=0,37; intervalo de confiança de 95% – IC 95%=0,17-0,83). Em relação à bulimia nervosa, o risco foi maior entre os estudantes que relataram complicações obstétricas (OR=2,62; IC 95%=1,03-6,67). Conclusão Observou-se associação entre fatores perinatais e neonatais com sintomas de transtornos alimentares em estudantes universitários.

Acute effects of high- and low-intensity exercise bouts on leukocyte counts.

BACKGROUND/OBJECTIVE: It is widely accepted that physical exercise may bring about changes in the immune system. Even acute bouts of exercise can alter the number and function of leukocytes, but the degree of white blood cell trafficking depends on the intensity and duration of exercise. The aim of this study was to analyze the acute and short-term effects of exercise intensity on leukocyte counts and leukocyte subsets. METHODS: Nine physically healthy, active young males (21.0 ± 1.9 years) underwent three experimental trials: high exercise intensity [80% peak oxygen consumption (VO2peak)], low exercise intensity (40% VO2peak), and the control condition (no exercise). Blood samples were collected prior to exercise, immediately after exercise, and 2 hours after exercise. Two-way analysis of variance for repeated measures was used to evaluate differences between the trials and the time-points, and to compare times within trials. RESULTS: There was a greater increase in the leukocyte count after high-intensity exercise, compared to the control condition (p < 0.01) and low-intensity exercise (p < 0.01). This effect was still present 2 hours after passive recovery (p < 0.01). CONCLUSION: When the same participants were submitted to different exercise intensities, the acute and short-term effects of exercise on white blood cells were intensity-dependent immediately after exercise (i.e., lymphocytosis and monocytosis) and 2 hours after passive recovery (i.e., neutrophilia).

Relation between leukocyte count, adiposity, and cardiorespiratory fitness in pubertal adolescents / Relação entre contagem de leucócitos, adiposidade e aptidão cardiorrespiratória em adolescentes púberes

Objective To compare the total and differential leukocyte count in obese and normal-weight adolescents, and to verify their possible relations with cardiorespiratory fitness and adiposity indicators. Methods A cross-sectional study conducted with 139 adolescents (107 obese and 32 normal weight) aged between 13 and 18 years. Cardiorespiratory fitness was determined by direct gas analysis during an incremental treadmill test. Total leukocytes and subsets were estimated by flow cytometry. Body composition was assessed by dual-energy X-ray absorptiometry. The t-test for independent samples was used for comparison between groups. The relation between leukocytes, cardiorespiratory fitness and adiposity indicators was verified by Pearson’s correlation and multiple linear regression (adjusted for age and body mass index) tests. Results Obese adolescents had higher leukocyte (8.12±2.36u/L x 103; p=0.001), neutrophil (4.33±1.86u/L x 103; p=0.002), and monocyte (0.70±0.22u/L x 103; p=0.002) counts compared to the levels of normal weight subjects. After the necessary adjustments, cardiorespiratory fitness had a negative association with leukocytes, neutrophils, and monocytes in boys. Conclusion Obese adolescents had higher total and differential leucocyte count when compared to normal weight individuals. We also observed a weak positive association between adiposity and total leukocyte, monocyte, and neutrophil counts, and in boys, a negative association between cardiorespiratory fitness and total count of leukocytes, monocytes, and neutrophils. .

Objetivo Comparar a contagem total e diferencial de leucócitos de adolescentes obesos e eutróficos, e verificar suas possíveis relações com a aptidão cardiorrespiratória e indicadores de adiposidade. Métodos Estudo transversal realizado com 139 adolescentes (107 obesos e 32 eutróficos), com idades entre 13 e 18 anos. A aptidão cardiorrespiratória foi determinada por análise direta de gases durante um teste incremental em esteira rolante. As contagens de leucócitos totais e subconjuntos foram estimadas por citometria de fluxo. A composição corporal foi avaliada pelo método de dupla energia de raios X. O teste t para amostras independentes foi utilizado para comparação entre os grupos. A relação entre leucócitos, aptidão cardiorrespiratória e indicadores de adiposidade foi verificada por meio dos testes de correlação de Pearson e regressão linear múltipla (ajustado para idade e índice de massa corporal). Resultados Os adolescentes obesos apresentaram leucócitos (8,12±2,36u/L x 103; p=0,001), neutrófilos (4,33±1,86u/L x 103; p=0,002) e monócitos (0,70±0,22u/L x 103; p=0,002) mais elevados em comparação com os níveis dos eutróficos. Após os ajustes necessários, a aptidão cardiorrespiratória foi negativamente associada com leucócitos, neutrófilos e monócitos em meninos. Conclusão Adolescentes obesos apresentaram maior contagem de leucócitos totais e subpopulações, quando comparados aos eutróficos. Observou-se também uma fraca relação positiva entre adiposidade e leucócitos totais, monócitos ...

Efeitos de diferentes intensidades de exercício sobre a concentração sérica de interleucinas / Effects of different exercise intensities on serum interleukins levels

O presente estudo teve como objetivo analisar os efeitos agudos e de curta duração de duas intensidades de exercício aeróbio sobre a concentração circulante de IL-6 e IL-10. Quinze homens jovens fisicamente ativos (21,0 ± 1,9 anos) foram submetidos a duas sessões de exercício ("crossover"): alta intensidade de exercício (AIE)- (80% VO2pico), e baixa intensidade de exercício (BIE)- (40% VO2pico), com intervalo de sete dias ("Wash out"). Amostras de sangue foram coletadas em tubos com EDTA, antes do exercício (basal), imediatamente após o exercício (agudo) e após 2 h de recuperação passiva. As concentrações séricas de IL-6 e IL-10 foram determinadas com a utilização de kits comerciais de ELISA. Os resultados demonstraram elevação aguda da IL- 6, em resposta ao AIE em relação ao BIE (p < 0,05), enquanto que a IL-10 apresentou maior redução sistêmica aguda para BIE em comparação a AIE (p < 0,05). Não houve diferença na variação das citocinas após 2 h do término do exercício. Conclui-se que ambas as sessões agudas de exercício são capazes de modular a concentração circulante destas citocinas, e que a magnitude das alterações são dependentes da intensidade do esforço

The aim of this study was to analyze the acute and short-term effects of high and low exercise intensities on IL-6 and IL-10. Fifteen young healthy physically active males (21.0 ± 1.9 yrs) were submitted to 2 experimental trials (cross-over) with a 7-dais wash-out: high exercise intensity (80% VO2peak) and low exercise intensity (40% VO2peak) session. Blood samples were collected before exercise (baseline), immediately after exercise (acute), and two hours after the end of the exercise session (2 h). IL-6 and IL-10 circulating levels were determinate by ELISA. The results demonstrated an acute increase in IL-6 levels after high intensity compared to low intensity exercise (p < 0.05), however, IL-10 presented an acute decrease in response to low intensity exercise (p < 0.05). No effects were observed after 2 h of recovery from the session. Thus we conclude that acute exercise sessions are able to modulate the circulating levels of the studies cytokines, and the magnitudes of these changes are dependent of the exercise intensity

Relation between leukocyte count, adiposity, and cardiorespiratory fitness in pubertal adolescents.

OBJECTIVE: To compare the total and differential leukocyte count in obese and normal-weight adolescents, and to verify their possible relations with cardiorespiratory fitness and adiposity indicators. METHODS: A cross-sectional study conducted with 139 adolescents (107 obese and 32 normal weight) aged between 13 and 18 years. Cardiorespiratory fitness was determined by direct gas analysis during an incremental treadmill test. Total leukocytes and subsets were estimated by flow cytometry. Body composition was assessed by dual-energy X-ray absorptiometry. The t-test for independent samples was used for comparison between groups. The relation between leukocytes, cardiorespiratory fitness and adiposity indicators was verified by Pearson's correlation and multiple linear regression (adjusted for age and body mass index) tests. RESULTS: Obese adolescents had higher leukocyte (8.12±2.36u/L x 103; p=0.001), neutrophil (4.33±1.86u/L x 103; p=0.002), and monocyte (0.70±0.22u/L x 103; p=0.002) counts compared to the levels of normal weight subjects. After the necessary adjustments, cardiorespiratory fitness had a negative association with leukocytes, neutrophils, and monocytes in boys. CONCLUSION: Obese adolescents had higher total and differential leucocyte count when compared to normal weight individuals. We also observed a weak positive association between adiposity and total leukocyte, monocyte, and neutrophil counts, and in boys, a negative association between cardiorespiratory fitness and total count of leukocytes, monocytes, and neutrophils.

Heart rate variability and its relationship with central and general obesity in obese normotensive adolescents.

OBJECTIVE: To analyze the relationship between the heart rate variability parameters and the indicators of central and general obesity in obese normotensive adolescents. METHODS: Seventyfour 13 to 18 year-old obese normotensive adolescents participated in this study. The indicators analyzed for central and general obesity were waist circumference and body mass index, respectively. Heart rate variability was obtained by heart rate monitoring. For this, the adolescents remained in a supine position for 7 minutes with controlled breathing. Parameters were obtained in time domain (standard deviation of all the RR intervals, root mean square of successive differences between the normal adjacent RR intervals and the percentage of adjacent intervals with more than 50ms) and frequency domain variables (low and high frequency bands and the sympathovagal balance). RESULTS: After adjustments for gender, age, and cardiorespiratory fitness, a negative correlation between the waist circumference and the root mean square of successive differences between the normal adjacent RR intervals (ß=-1.51; standard error=0.56; p<0.05) and the percentage of adjacent intervals with more than 50 ms (ß=-0.96; standard error=0.34; p<0.05) were observed, while the body mass index showed no significant correlation with any heart rate variability parameter (p>0.05). CONCLUSION: Central obesity is a better discriminator than general obesity of autonomic cardiac dysfunction in obese normotensive adolescents.

Relação entre variabilidade da frequência cardíaca e indicadores de obesidade central e geral em adolescentes obesos normotensos / Heart rate variability and its relationship with central and general obesity in obese normotensive adolescents

OBJETIVO: Analisar a relação entre os parâmetros da variabilidade da frequência cardíaca e os indicadores de obesidade central e geral em adolescentes obesos normotensos. MÉTODOS: Participaram deste estudo 74 adolescentes obesos normotensos, com idade entre 13 e 18 anos. Os indicadores de obesidade central e geral analisados foram a circunferência da cintura e o índice de massa corporal, respectivamente. A variabilidade da frequência cardíaca foi obtida por meio de monitor de frequência cardíaca. Para tanto, os adolescentes permaneceram na posição supina durante 7 minutos e com respiração controlada. Foram calculadas as variáveis do domínio do tempo (desvio padrão de todos os intervalos RR, a raiz quadrada da média do quadrado das diferenças entre os intervalos RR normais adjacentes e a percentagem dos intervalos adjacentes com mais de 50ms) e do domínio da frequência (bandas de baixa e alta frequência e o balanço simpatovagal). RESULTADOS: Após ajustes para gênero, idade e capacidade cardiorrespiratória, foi observada relação negativa entre a circunferência da cintura e a raiz quadrada da média do quadrado das diferenças entre os intervalos RR normais adjacentes (ß=-1,51; erro padrão=0,56; p<0,05) e a percentagem dos intervalos adjacentes com mais de 50ms (ß=-0,96; erro padrão=0,34; p<0,05), enquanto o índice de massa corporal não teve relação significante com nenhum parâmetro da variabilidade da frequência cardíaca (p>0,05). CONCLUSÃO: A obesidade central é melhor discriminadora de disfunção autonômica cardíaca em adolescentes obesos normotensos do que a obesidade geral.

OBJECTIVE: To analyze the relationship between the heart rate variability parameters and the indicators of central and general obesity in obese normotensive adolescents. METHODS: Seventyfour 13 to 18 year-old obese normotensive adolescents participated in this study. The indicators analyzed for central and general obesity were waist circumference and body mass index, respectively. Heart rate variability was obtained by heart rate monitoring. For this, the adolescents remained in a supine position for 7 minutes with controlled breathing. Parameters were obtained in time domain (standard deviation of all the RR intervals, root mean square of successive differences between the normal adjacent RR intervals and the percentage of adjacent intervals with more than 50ms) and frequency domain variables (low and high frequency bands and the sympathovagal balance). RESULTS: After adjustments for gender, age, and cardiorespiratory fitness, a negative correlation between the waist circumference and the root mean square of successive differences between the normal adjacent RR intervals (ß=-1.51; standard error=0.56; p<0.05) and the percentage of adjacent intervals with more than 50 ms (ß=-0.96; standard error=0.34; p<0.05) were observed, while the body mass index showed no significant correlation with any heart rate variability parameter (p>0.05). CONCLUSION: Central obesity is a better discriminator than general obesity of autonomic cardiac dysfunction in obese normotensive adolescents.

Efeitos de diferentes intensidades de treinamento físico aeróbio sobre a concentração circulante de leucócitos em adolescentes obesos submetidos à intervenção multidisciplinar / Effects of different aerobic training intensity on leukocyte in obese adolescents submitted to a multidisciplinary therapy

O objetivo do presente estudo foi comparar os efeitos do treinamento aeróbio de alta intensidade (TAI) com o de baixa intensidade (TBI) sobre a concentração circulante de leucócitos em adolescentes obesos. Quarenta e três adolescentes obesos (34,4±4,3 kg/m²) de ambos os gêneros (13 meninos e 30 meninas), com idade entre 13 e 18 anos, foram submetidos de forma aleatória ao TAI (intensidade correspondente ao limiar ventilatório I; N=20) ou TBI (intensidade correspondente a 20% abaixo do limiar ventilatório I; N=23) durante 12 semanas. Todos os voluntários receberam o mesmo acompanhamento clínico, psicológico e nutricional. Para ambos os grupos as sessões de exercício foram isocalóricas (350Kcal). A concentração total de leucócitos e subpopulações (monócitos, linfócitos e neutrófilos) foram determinadas por citometria de fluxo fluorescente antes (pré) e após (pós) a intervenção. Para a análise entre grupos e momentos foi utilizada ANOVA two way para medidas repetidas, com post-hoc de Fisher. Correlações entre as variáveis foram analisadas por meio da correlação de Pearson. Os resultados demonstraram redução na concentração circulante de monócitos tanto no TAI (pré: 0,63+0,10; pós: 0,3+0,10 ? p<0,001) quanto no TBI (pré: 0,73+0,27; pós: 0,39+0,19 ? p<0,001), sem diferença entre os grupos. Adicionalmente o foi verificado elevação dos neutrófilos apenas no grupo TAI (p=0,008). Dessa forma, podemos concluir que treinamento físico aeróbio, independente da intensidade, é efetivo no controle do estado inflamatório em adolescentes obesos, via redução da concentração circulante de monócitos.

The aim of this study was to compare the effects of a high intensity (HIT) vs. a low intensity (LIT) aerobic exercise training on leukocytes levels in obese adolescents. Forty-three obese (34.4 +4.3 kg/m²) from both genders (13 boys and 30 girls) aged between 13 and 18 years underwent randomically to HIT (intensity corresponding to ventilatory threshold I, N=20) or LIT (intensity corresponding to 20% below ventilatory threshold I, N=23) during 12 weeks. All volunteers accomplish the clinical follow-up (1x/month), psychological and nutritional counseling (1x/week). For both groups exercise sessions were isocaloric (150Kcal). Total leukocytes and subpopulations (monocytes, lymphocytes and neutrophils) were determined by fluorescence flow cytometry before and after intervention. For analysis between groups and time were used two-way ANOVA for repeated measures with Fisher as post-hoc. Correlations between variables were analyzed by Pearson´s correlation. The results showed reduction on circulating levels of monocytes in TAI (pre: 0.63+0.10; post: 0.3+0.10 ? p<0.001) as well as in TBI (pre: 0.73+0.27; post: 0.39+0.19 ? p<0.001), without groups differences. In addition it was verified a rise in neutrophils values (p=0.008). Thus we can conclude that aerobic exercise, regardless of intensity, is effective in controlling the inflammatory status in obese adolescents by reducing monocytes circulating levels.

Efeitos agudos de diferentes intensidades de exercício sobre a ingestão alimentar pós-exercício / Acute effects of exercise intensity on pos-exercise food intake in young men

O objetivo do presente estudo foi verificar os efeitos agudos de diferentes intensidades de exercício aerróbio (40 e 80 por cento do VO2pico) sobre a ingestão alimentar pós-exercício. Participaram do estudo 18 adultos jovens, eutróficos (22,20 ± 1,72 kg/m²) e fisicamente ativos. Todos os sujeitos foram submetidos aleatoriamente a três condições experimentais: controle (sem exercício); EBI, exercício de baixa intensidade (40 por cento doVO2pico) e EAI, exercício de alta intensidade (80 por cento do VO2pico). As sessões de exercício foram isocalróricas (350 kcal). Após 120 minutos de recuperação passiva, os voluntários tinham livre acesso a um "buffet" variado de alimentos, a ingestão alimentar foi determinada atravéz da pesagem dos alimentos ingeridos. Os dados alimentares obtidos foram então tabulados e analisados por meio do "software" Nutwin 6.0 (UNIFESP, 2002), para estimativa do consumo energético total (kcal) e ingestão dos macronutrientes (carboidratos, proteínas e lipídeos) em gramas. Os resultados não demonstram nenhuma diferença na ingesto alimentar entre as condições experimentais analisadas. Dessa forma, podemos concluir que a ingestão alimentar pós-exercício não se mostrou dependente da intensidade do esforóo em curto prazo em indivíduos adultos jovens fisicamente ativos.

The aim of this study was to investigate the acute effects of different aerobic exercise intensities (40 and 80 percent do VO2peak) on post-exercise food intake. The sample was composed of eighteen healthy, physically active young men, of normal weight (22.20 ± 1.72 kg/m²). Subjects were randomly submitted to three experimental conditions: control (no exercise); low-intensity exercise (LIE -40 percent of VO2peak) and high-intensity exercise (HIE- 80 percent of VO2peak). Exercise trials were iso-caloric (350 Kcal). After 120 minutes of passive recovery, the volunteers had free access to a variety food buffet, and food intake was determined thru food weight. Data was analyzed by the software Nutwin 6.0 (UNIFESP, 2002) to estimate total energy intake (kcal) and consumption of the macronutrients (carbohydrates, proteins and lipids). The results suggest that food intake after exercise showed no significant differences between the experimental conditions. In conclusion, food intake after exercise is not dependent on exercise intensity in healthy young men.