Time Reallocations From Sedentary Behavior to Physical Activity and Cardiovascular Risk Factors in Children and Adolescents: A Systematic Review.

BACKGROUND: Recent statistical approaches have allowed consideration of the integrated relationships between sedentary behavior (SB) and physical activity (PA) with different health outcomes. The present paper aimed to systematically review the literature and synthesize evidence about associations between hypothetical reallocations from SB to different PA intensities and cardiovascular risk factors in youth. METHODS: A systematic search of 8 databases was performed. Observational studies with a population of children and/or adolescents and based on statistical analysis that investigated the associations between time reallocations from SB to PA and cardiovascular risk factors were included. RESULTS: Twenty-eight studies met the inclusion criteria. Level of evidence (derived from cross-sectional studies) indicated that the reallocation from SB to moderate to vigorous PA was beneficially associated with adiposity, cardiorespiratory fitness, and cardiometabolic biomarkers in youth. Reallocation from SB to light PA was not associated with the analyzed outcomes. Associations derived from longitudinal studies were mostly inconclusive. CONCLUSION: Cardiovascular risk factors could be improved by increasing moderate to vigorous PA at the expense of time spent in SB in pediatric populations. Prospective studies or studies investigating the effects of reallocating sedentary bouts to PA are needed.

Effects of High-Intensity Interval Training on Central Blood Pressure: A Systematic Review and Meta-Analysis. / Efeitos do Treinamento Intervalado de Alta Intensidade sobre a Pressão Arterial Central: Uma Revisão Sistemática e Metanálise.

Central blood pressure (cBP) is considered an independent predictor of organ damage, cardiovascular events and all-cause mortality. Evidence has shown that high intensity interval training (HIIT) is superior to moderate-intensity continuous training (MICT) for improving cardiorespiratory fitness and vascular function. However, the effects of these aerobic training modalities on cBP have not yet been properly reviewed.This meta-analysis aims to investigate to effects of HIIT versus MICT on cBP.We conducted a meta-analysis of randomized controlled trials that compared HIIT versus MICT on cBP. Primary outcomes were measures of central systolic blood pressure (cSBP) and central diastolic blood pressure (cDBP). Peripheral systolic blood pressure (pSBP) and diastolic blood pressure (pDBP), pulse wave velocity (PWV) and maximal oxygen uptake (VO2max) were analyzed as second outcomes. Meta-analysis of mean differences (MD) was conducted using the random effects model.Our study included 163 patients enrolled in six trials. We found that HIIT was superior to MICT in reducing the cSBP (MD = -3.12 mmHg, 95% CI: -4.75 to -1.50, p = 0.0002) and SBP (MD = -2.67 mmHg, 95% CI: -5.18 to -0.16, p = 0.04), and increasing VO2max(MD = 2.49 mL/kg/min, 95% CI: 1.25 to 3.73, p = 0.001). However, no significant differences were reported for cDBP, DBP and PWV.HIIT was superior to MICT in reducing the cSBP, which suggests its potential role as a non-pharmacological therapy for high blood pressure.

A pressão arterial central (PAc) é considerada um preditor independente de lesão de órgão, eventos cardiovasculares e mortalidade por todas as causas. Evidências mostram que o treino intervalado de alta intensidade (HIIT) é superior ao treino contínuo de intensidade moderada (MICT) na melhoria da aptidão cardiorrespiratória e da função vascular. No entanto, os efeitos dessas modalidades de treino aeróbico sobre a PAc não foram propriamente revisados. Esta metanálise tem como objetivo investigar os efeitos do HIIT versus MICT sobre a PAc.Conduzimos uma metanálise de ensaios controlados randomizados que compararam HIIT versus MICT sobre a PAc. Os desfechos primários foram Pressão Arterial Sistólica (PAS) central (PASc) e Pressão Arterial Diastólica central (PADc). A PAS periférica (PASp), a PAD periférica (PADp), a Velocidade de Onda de Pulso (VOP) e a captação máxima de oxigênio (VO2max) foram analisadas como desfechos secundários. A metanálise das diferenças médias (DM) foi conduzida usando modelos de efeitos aleatórios.Nosso estudo incluiu 163 pacientes recrutados em seis ensaios. Encontramos que HIIT foi superior ao MICT em reduzir PASc (DM = -3,12 mmHg, IC95% -4,75 ­ 1,50, p = 0,0002) e PAS (DM = -2,67 mmHg, IC95% -5,18 ­ -0,16, p = 0,04) e aumentar VO2max (DM = 2,49 mL/Kg/min, IC95% 1,25 ­ 3,73, p = 0,001). No entanto, não foram relatadas diferenças quanto à PADc, PAD ou VOP. O HIIT foi superior ao MICT em reduzir PASc, sugerindo seu potencial papel como uma terapia não farmacológica para a pressão arterial elevada.

Efeitos do Treinamento Intervalado de Alta Intensidade sobre a Pressão Arterial Central: Uma Revisão Sistemática e Metanálise / Effects of High-Intensity Interval Training on Central Blood Pressure: A Systematic Review and Meta-Analysis

Resumo A pressão arterial central (PAc) é considerada um preditor independente de lesão de órgão, eventos cardiovasculares e mortalidade por todas as causas. Evidências mostram que o treino intervalado de alta intensidade (HIIT) é superior ao treino contínuo de intensidade moderada (MICT) na melhoria da aptidão cardiorrespiratória e da função vascular. No entanto, os efeitos dessas modalidades de treino aeróbico sobre a PAc não foram propriamente revisados. Esta metanálise tem como objetivo investigar os efeitos do HIIT versus MICT sobre a PAc.Conduzimos uma metanálise de ensaios controlados randomizados que compararam HIIT versus MICT sobre a PAc. Os desfechos primários foram Pressão Arterial Sistólica (PAS) central (PASc) e Pressão Arterial Diastólica central (PADc). A PAS periférica (PASp), a PAD periférica (PADp), a Velocidade de Onda de Pulso (VOP) e a captação máxima de oxigênio (VO2max) foram analisadas como desfechos secundários. A metanálise das diferenças médias (DM) foi conduzida usando modelos de efeitos aleatórios.Nosso estudo incluiu 163 pacientes recrutados em seis ensaios. Encontramos que HIIT foi superior ao MICT em reduzir PASc (DM = -3,12 mmHg, IC95% -4,75 - 1,50, p = 0,0002) e PAS (DM = -2,67 mmHg, IC95% -5,18 - -0,16, p = 0,04) e aumentar VO2max (DM = 2,49 mL/Kg/min, IC95% 1,25 - 3,73, p = 0,001). No entanto, não foram relatadas diferenças quanto à PADc, PAD ou VOP. O HIIT foi superior ao MICT em reduzir PASc, sugerindo seu potencial papel como uma terapia não farmacológica para a pressão arterial elevada.

Abstract Central blood pressure (cBP) is considered an independent predictor of organ damage, cardiovascular events and all-cause mortality. Evidence has shown that high intensity interval training (HIIT) is superior to moderate-intensity continuous training (MICT) for improving cardiorespiratory fitness and vascular function. However, the effects of these aerobic training modalities on cBP have not yet been properly reviewed.This meta-analysis aims to investigate to effects of HIIT versus MICT on cBP.We conducted a meta-analysis of randomized controlled trials that compared HIIT versus MICT on cBP. Primary outcomes were measures of central systolic blood pressure (cSBP) and central diastolic blood pressure (cDBP). Peripheral systolic blood pressure (pSBP) and diastolic blood pressure (pDBP), pulse wave velocity (PWV) and maximal oxygen uptake (VO2max) were analyzed as second outcomes. Meta-analysis of mean differences (MD) was conducted using the random effects model.Our study included 163 patients enrolled in six trials. We found that HIIT was superior to MICT in reducing the cSBP (MD = -3.12 mmHg, 95% CI: -4.75 to -1.50, p = 0.0002) and SBP (MD = -2.67 mmHg, 95% CI: -5.18 to -0.16, p = 0.04), and increasing VO2max(MD = 2.49 mL/kg/min, 95% CI: 1.25 to 3.73, p = 0.001). However, no significant differences were reported for cDBP, DBP and PWV.HIIT was superior to MICT in reducing the cSBP, which suggests its potential role as a non-pharmacological therapy for high blood pressure.

ADRB2 gene influences responsiveness to physical exercise programs: A longitudinal study applied to overweight or obese Brazilian children and adolescents.

We aimed to investigate whether the expression levels and polymorphisms in the ADRB2 gene have influenced the anthropometric and cardiometabolic outcomes changes in obese/overweight children submitted to physical exercise programs. This longitudinal study included 197 overweight or obese children aged 10-16 years, submitted to physical exercise programs - three sessions per week for 12 weeks. Anthropometric and cardiometabolic profile was collected before and after interventions. The ADRB2 gene expression levels were also measured in these two moments in a small intervention group (n = 17) and a control group (n = 18). Arg16Gly and Gln27Glu polymorphisms were genotyped. A positive correlation between ADRB2 expression and loss of body fat (%) (p = 0.038) was observed, which remained after sex and BMI change corrections. Carriers of the Glu27Glu genotype presented a better response to physical exercise programs regarding their triglycerides levels and triglyceride-glucose index (p = 0.001 for both). The participants' responsiveness to physical exercise programs showed variation due to the ADRB2 gene expression and the Gln27Glu polymorphism. A more significant loss of body fat was associated with higher levels of ADRB2 expression, and the Glu27Glu genotype was associated with a better cardiometabolic response. The Arg16Gly polymorphism did not show interaction with the responsiveness to physical exercise.

Effects of table tennis practice on balance and physical fitness in the elderly / Efeitos da prática de tênis de mesa no equilíbrio e aptidão física em idosos

ABSTRACT The Table Tennis game does not involve large displacements by the practitioner in the environment, a characteristic that can promote greater safety for the elderly in locomotor terms. In addition, it needs coordination, agility, speed of reaction, dynamic balance, which have been the focus of current recommendations of physical activity for the health of adults and the elderly. The aim of this study is to investigate the effects of table tennis practice on physical and functional fitness in the elderly. This quasi-experimental research with a parallel and controlled design. The sample consisted of 16 elderly people, allocated 8 in the experimental group (EG) and 8 in the control group (CG). The research lasted 18 weeks, with 2 weeks of evaluation (initial and final) and 16 weeks of intervention. Physical fitness assessments were carried out using the agility and balance and functional fitness tests. In the intra-group comparison (pre-post intervention), EG showed a significant difference for the variable agility (pre: 15.6 ± 1.2 s; post: 14.7 ± 0.7 s). Also, the EG showed a reduction in Area (pre: 11.00±3.32 cm2; post: 6.52±3.06 cm2), AP Amplitude (pre: 4.92±2.77 cm; post: 3.28±0.58 cm) and ML speed (pre: 2.77±1.07 cm/s; post: 2.31±1.03 cm/s) in the Tandem posture with eyes open. Our findings highlight the importance of a Table Tennis program, administered twice a week and consisted of low to moderate intensity activities, to promote a beneficial effect on the agility and balance of physically active elderly people.

RESUMO O jogo de Tênis de Mesa não envolve grandes deslocamentos do praticante no ambiente, característica que pode promover maior segurança ao idoso em termos locomotores. Além disso, precisa de coordenação, agilidade, velocidade de reação, equilíbrio dinâmico, que têm sido foco das atuais recomendações de atividade física para a saúde de adultos e idosos. O objetivo deste estudo é investigar os efeitos da prática de tênis de mesa na aptidão física e funcional de idosos. Esta pesquisa apresenta delineamento quase experimental com um desenho paralelo e controlado. A amostra foi composta por 16 idosos, alocados 8 no grupo experimental (GE) e 8 no grupo controle (GC). A pesquisa teve duração de 18 semanas, sendo 2 semanas de avaliação (inicial e final) e 16 semanas de intervenção. As avaliações da aptidão física foram realizadas por meio dos testes de agilidade e equilíbrio e aptidão funcional. Na comparação intragrupo (pré-pós intervenção), o GE apresentou diferença significativa para a variável agilidade (pré: 15,6 ± 1,2 s; pós: 14,7 ± 0,7s). Além disso, o GE apresentou redução na Área (pré: 11,00±3,32 cm2; pós: 6,52±3,06 cm2), Amplitude AP (pré: 4,92±2,77 cm; pós: 3,28±0,58 cm) e velocidade ML (pré: 2,77±1,07 cm/s; pós: 2,31±1,03 cm/s) na postura Tandem com os olhos abertos. Nossos achados destacam a importância de um programa de Tênis de Mesa, administrado duas vezes por semana e composto por atividades de baixa a moderada intensidade, para promover um efeito benéfico na agilidade e equilíbrio de idosos fisicamente ativos.

Impact of resistance exercise order on postexercise hemodynamic measures in middle-aged and older women

Abstract Aim: to compare the impact of different resistance exercise orders on postexercise hemodynamic measures in resistance-trained nonhypertensive middle-aged and older women. Methods: Twenty-three women (age 50-78 yrs) were randomized into two resistance training (RT) groups: one group started training sessions performing multi-joint exercises followed by single-joint exercises (MS, n = 12; 58.92 ± 5.53 yrs), while the other group performed their sessions in the opposite order (SM, n = 11; 57.93 ± 11.89 yrs). Both groups performed their RT sessions composed of 7 exercises performed in 3 sets of 10-15 repetitions maximum. Blood pressure was measured by automated equipment during pre-training and at 10, 20, 30, 40, 50, and 60 min after the training session. Results: Repeated-measures analysis of variance (ANOVA) identified an isolated effect of time only for systolic blood pressure (p = 0.003) with statistically significant reductions in pre-session measurement at 60 min post-session in both groups (MS: 117.67 ± 15.89 mmHg vs. 111.25 ± 11.84 mmHg and SM: 118.64 ± 15.13 mmHg vs. 111.50 ± 15.62 mmHg). Regarding diastolic blood pressure and subjective perception of effort, no difference was identified between groups (p > 0.05). Conclusion: We conclude that a RT session can promote post-exercise hypotension for systolic blood pressure after 60 min of recovery in middle-aged and nonhypertensive older women regardless of the exercise order.

Atividade física para crianças e jovens: Guia de Atividade Física para a População Brasileira / Physical activity for children and youth: Physical Activity Guidelines for the Brazilian Population

A prática regular de atividade física promove benefícios fisiológicos, psicológicos e sociais na vida de crianças e jovens. Apesar da alta prevalência de jovens que não praticam atividade física em nosso país e de termos uma boa colocação no ranking mundial de produção acadêmica sobre pesquisa na área de atividade física e saúde, ainda não havia sido publicadas as recomendações brasileiras de atividade física. O objetivo deste artigo consistiu em descrever como foi desenvolvido o capítulo para crianças e jovens de 6 a 17 anos do Guia de Atividade Física para População Brasileira e apresentar as principais recomendações para esta faixa etária. A construção do capítulo para crianças e jovens envolveu as seguintes etapas: a) revisão de literatura; b) redação da versão preliminar do capítulo; c) processo de escuta com o público alvo referente ao capítulo e especialistas da área de promoção da atividade física; d) realização de consulta pública e; e) redação da versão final do capítulo. Os tópicos apresentados abordam exemplos de atividades físicas praticadas em diferentes domínios; recomendações para a prática (tipos, intensidade, frequência, duração e as formas que a mesma pode ser estruturada). São apresentadas orientações para jovens, pais/responsáveis e professores sobre como adotar e manter um estilo de vida mais ativo fisicamente, assim como sugestões para reduzir o tempo em comportamento sedentário. A elaboração de um guia nacional de atividade física para a população brasileira foi algo inédito, e resultou de um esforço conjunto entre diversos setores da sociedade

Regular physical activity promotes physiological, psychological and social benefits in the lives of children and adolescents. Despite the high prevalence of young people who do not physically activity in our country, and that we have a good ranking in world academic production on research in the physical activity and health area, Brazilian recommendations for physical activity had not been published until then. The aim of this article was to describe how the chapter for children and young people aged 6-17 years of Physical Activity Guidelines for the Brazilian Population was developed and to present the main recommendations for this age group. The construction of the chapter for children and young people involved the following steps: a) lit-erature review; b) writing the preliminary version of the chapter; c) listening process of the target audience for the chapter and specialists in the physical activity promoting area; d) public consultation; and e) writing the final version of the chapter. The topics presented cover examples of physical activities practised in different domains; recommendations for practice (types, intensity, frequency, duration and the ways in which it can be structured). Guidance is provided for young people, parents/guardians and teachers about how to adopt and maintain a more physically active lifestyle, as well as suggestions for reducing time in sedentary behaviour. The construction of a national guidelines about physical activity for Brazilian population is something un-precedented, and resulted from a joint effort of several departments of society

Physical Activity, Sport Practice and Cardiovascular Risk Factors in Workers From a Public Hospital: A Trajectory Analysis.

Background: Studies have demonstrated the positive effects of physical activity on cardiovascular risk factors. Longitudinal studies using modeled trajectories are necessary to understand patterns of physical activity and association with cardiovascular risk factors. Objective: To analyze the association between sports practice in young people and current physical activity with the trajectory of cardiovascular risk factors in workers at a public hospital. Methods: Four hundred and seventeen workers was followed for four years reporting Physical Activity, health status, lifestyle behaviors and socio-demographic characteristics. Group-based trajectory modeling identified the trajectories of PA and associations with time-stable and time-varying covariates. We considered a range of sociodemographic and health and lifestyle factors as potential covariates. Results: The results shows the association between participation in sports activities in youth and current physical activity and trajectories of cardiovascular risk, adjusted for sex and age (p < 0.05). Adults who reported having played sports in their youth and are currently active have a lower risk of having a history of obesity and low HDL-c than workers who did not play sports in their youth and are currently sedentary 0.690 (0.565-0.844) obesity, 0.647 (0.500-0.837) low HDL-c. Conclusion: The practice of sports in youth and current physical activity is a protective factor against the trajectory of obesity and low HDL-c, mainly in female workers. Programs to encourage the practice of physical activity should be carried out in order to reduce cardiovascular risk factors and prevent chronic diseases in workers.

Cardiac autonomic control following resistance exercise with different set configurations in apparently healthy young men: A crossover study.

We compared the heart rate variability (HRV) after a low-intensity resistance exercise (LI-RE) with short (SSC/LI-RE) and long (LSC/LI-RE) set configurations, composed of 10 and 20 repetitions, respectively. Randomly, ten young males performed one session of both RE protocols. Time- and frequency-domain, and nonlinear HRV parameters were assessed at baseline and 20-30 and 50-60 min after protocols. Significant reductions in time-domain, frequency-domain and nonlinear HRV parameters were observed at 20-30 min and 50-60 min after LSC/LI-RE compared to baseline. A low-intensity RE with a long set configuration induces an acute vagal withdrawal and loss of heart rate complexity after exercise.

Tri-ponderal mass index as a tool for insulin resistance prediction in overweight adolescents: A cross-sectional study.

OBJECTIVE: The aims of this study were to assess the capacity of tri-ponderal mass index (TMI) to screen and predict insulin resistance (IR) in overweight Brazilian adolescents, comparing it with body mass index (BMI) predictive capacity; and to verify the IR predictive capacity of other assessment tools such as waist circumference (WC), and waist-to-height ratio (WHR). METHODS: A cross-sectional study was carried out with 217 overweight adolescents, from both sexes, between 12 and 18 y of age. The participants were classified as having IR according to a previous established cutoff point of ≤3.16. IR was determined by the homeostasis model assessment of insulin resistance. The other assessment tools were measured with standard protocols. RESULTS: There was no difference between TMI and BMI to explain the presence of IR. In girls, BMI presented a slightly better predictive capacity to explain IR than TMI. Moreover, WC was reported to be the most effective IR screening methods for girls. Receiver operating characteristic curves showed that TMI and BMI presented similar values of sensibility and specificity for boys. Nevertheless, BMI had a better sensibility and TMI had a better specificity for girls. Interestingly, WC demonstrated a strong sensibility for both sexes. CONCLUSIONS: TMI did not present a superior predictive accuracy for IR screening in overweight Brazilian adolescents when compared with BMI. TMI and BMI presented similar values of sensitivity and specificity for boys and WC a slightly superior IR predictive capacity for girls.

A Neurovisceral Integrative Study on Cognition, Heart Rate Variability, and Fitness in the Elderly.

The association between physical fitness and cognitive performance has been widely investigated in the literature. However, the neurophysiological mechanisms underlying this relationship are not yet clear. Here, we aim to evaluate the interactions between executive function measures, heart rate variability (HRV), and physical fitness in the context of the neurovisceral integration (NVI) theory. Twenty-eight healthy elderly subjects (>60 years) were submitted to evaluation of executive performance with three computerized tests: the N-back test measured working memory capacity, the Stroop Color test evaluated inhibitory control and selective attention, and the Wisconsin Card Sorting Test (WCST) evaluated abstract reasoning and cognitive flexibility. We also used the Physical Testing Battery for the Elderly to measure aerobic capacity, dynamic balance, upper body flexibility, and handgrip strength. Our results confirm the relationship between executive function and physical fitness, particularly between working memory, cardiorespiratory fitness, and dynamic balance. We also demonstrate an association between executive performance and HRV in older people, corroborating previous results from other groups obtained in young adults. However, our regression models did not indicate that HRV mediates the relationship between cognition and physical fitness in the elderly, suggesting that age-related degeneration of autonomic control can affect aspects of NVI in this population.

Effect of physical training on exercise-induced bronchospasm in young asthmatics / Efeito do treinamento físico no broncoespasmo induzido pelo exercício em jovens asmáticos / Efecto del entrenamiento físico en el broncoespasmo inducido por el ejercicio en jóvenes asmáticos

ABSTRACT Introduction: Asthma is the most common chronic disease in childhood and its prevalence has increased in recent years. Although regular physical activity (PA) is considered to be beneficial for the health of asthmatics, especially children and adolescents, it can also be one of the elements that triggers asthma. This is known as exercise-induced bronchospasm (EIB), and is considered one of the factors that limits asthmatics' participation in PA. Objective: This study aims to review the effects of physical conditioning on EIB in asthmatic children and adolescents. Methods: A systematic review was carried out on the Pubmed, Bireme and Web of Science databases, considering publications from 1998 to April 2019. Results: Eight articles were retrieved; five of the articles presented no significant difference in EIB parameters after physical training, and three demonstrated significant benefits in EIB. Conclusion: There is insufficient evidence that physical training helps reduce the frequency and severity of EIB in young asthmatics. There are still few studies that seek to show the effect of a physical training program on the improvement of EIB in children and adolescents. It is suggested that further randomized clinical trials be conducted, to investigate the effects of physical training on EIB parameters in children and adolescents. Level of Evidence II; Systematic review.

RESUMO Introdução: A asma brônquica é a doença crônica mais comum na infância e a sua prevalência tem aumentado nos últimos anos. Apesar da prática regular de atividade física (AF) ser considerada benéfica para a saúde do asmático, especialmente, em crianças e adolescentes, ela também pode ser um dos elementos desencadeantes da asma, conhecido como broncoespasmo induzido pelo exercício (BIE) que é considerado como um dos fatores que limita a participação de asmáticos na AF. Objetivo: A presente pesquisa tem como objetivo revisar os efeitos do condicionamento físico sobre o BIE em crianças e adolescentes asmáticos. Métodos: Realizou-se uma pesquisa bibliográfica nas bases Pubmed, Bireme e Web of Science, considerando publicações no período de 1998 a abril de 2019. Resultados: Foram selecionados oito artigos, sendo que cinco não apresentaram diferença significativa nas variáveis do BIE após o treinamento físico e três demonstraram benefícios significativos. Conclusão: Não há evidências suficientes de que o treinamento físico contribua para redução na frequência e/ou gravidade do BIE em jovens asmáticos. Ainda são poucos os estudos que buscam mostrar o efeito de um programa de treinamento físico na melhora do BIE em crianças e adolescentes. Sugere-se a realização de mais ensaios clínicos randomizados que investiguem os efeitos do treinamento físico sobre as variáveis do BIE em crianças e adolescentes. Nível de evidência II; Revisão sistemática.

RESUMEN Introducción: El asma bronquial es la enfermedad crónica más común en la infancia y su prevalencia ha aumentado en los últimos años. A pesar de que la práctica regular de actividad física (AF) sea considerada benéfica para la salud del asmático, especialmente en niños y adolescentes, también puede ser uno de los elementos desencadenantes del asma, conocido como broncoespasmo inducido por el ejercicio (EIB), que es considerado como uno de los factores que limitan la participación de asmáticos en la AF. Objetivo: La presente investigación tiene como objetivo revisar los efectos del acondicionamiento físico sobre el EIB en niños y adolescentes asmáticos. Métodos: Se realizó una búsqueda bibliográfica en las bases de datos Pubmed, Bireme y Web of Science, considerando publicaciones en el período de 1998 a abril de 2019. Resultados: Fueron seleccionados ocho artículos, siendo que cinco no presentaron diferencia significativa en las variables del EIB después del entrenamiento físico y tres demostraron beneficios significativos. Conclusión: No hay evidencias suficientes de que el entrenamiento físico contribuya para la reducción en la frecuencia y/o gravedad del EIB en jóvenes asmáticos. Todavía son pocos los estudios que buscan mostrar el efecto de un programa de entrenamiento físico en la mejora del EIB en niños y adolescentes. Se sugiere la realización de más ensayos clínicos aleatorios que investiguen los efectos del entrenamiento físico sobre las variables del EIB en niños y adolescentes. Nivel de evidencia II; Revisión sistemática.

Triglyceride/glucose index is a reliable alternative marker for insulin resistance in South American overweight and obese children and adolescents.

Background The aim of the present study was to investigate the correlation between the triglyceride/glucose index (TyG index) and homeostasis model assessment of insulin resistance (HOMA-IR). Additionally, we compared the ability of the TyG index and triglycerides/high-density lipoprotein cholesterol (TG/HDL-c) index and the combination of these two indices (TyG index plus TG/HDL-c) to predict insulin resistance (IR) in South American overweight and obese children and adolescents. Methods A cross-sectional study was carried out in 345 overweight adolescents aged 10-18 years, from both the sexes. The TyG index was calculated as Ln (fasting triglycerides [mg/dL] × fasting glucose [mg/dL])/2, while the TG/HDL-c index was calculated by the division of TG (mg/dL) by HDL-c (mg/dL). HOMA-IR was calculated with the formula: fasting insulin (FI) (U/mL) × fasting glucose (mmol/L)/22.5. The cut-off point used to determine the presence of IR was HOMA-IR ≥ 3.16. Results The TyG index showed a positive correlation with HOMA-IR. The area under the receiver operating characteristic (ROC) curve of the TyG index was 0.74, indicating good sensitivity (75.7%) and specificity (67.4%). Furthermore, the TyG index cut-off point of >4.44 was established for IR prediction in this population. Conclusions The TyG index is a simple and cost-effective surrogate marker of IR in South American overweight children and adolescents. Moreover, due to its good accessibility, it can be used in large epidemiological studies.

Adrb2 gln27glu polymorphism associated with adiposity indicators and il-10 in adolescents / Polimorfismo adrb2 gln27glu associado a indicadores de adiposidade e il-10 em adolescentes / Polimorfismo adrb2 gln27glu asociado a indicadores de adiposidad e il-10 en adolescentes

ABSTRACT Introduction: Studies of association between obesity and genetic factors have demonstrated a significant contribution of polymorphisms related to body fat distribution and subclinical inflammatory process. Objective: To investigate the association between genotypes of the Gln27Glu polymorphism of the ADRB2 gene and indicators of adiposity, inflammatory markers, metabolic parameters and parameters of physical fitness in overweight adolescents. Methods: A total of 44 male and female adolescents, aged between 13 and 17 years, with positive clinical diagnosis of overweight, were divided into two groups according to the Gln27Glu polymorphism genotypes of the ADRB2 gene: a) Group of carriers of the 27Glu allele (Gln27Glu/Glu27Glu) (n = 22); b) Group of non-carriers of the 27Glu allele (Gln27Gln) (n = 22). Both groups were evaluated for body composition, sexual maturation, cardiorespiratory fitness variables and indicators of muscle strength. Basal glycemia and insulin, lipid profile and inflammatory profile were measured. Abdominal subcutaneous and visceral adiposities were evaluated by ultrasonography. Genotyping of the Gln27Glu polymorphism of the ADRB2 gene was performed by the Taqman allelic discrimination assay. Results: The genotype frequency found was: Gln/Gln (n = 22) (50.0%), Gln/Glu (n = 18) (41.0%) and Glu/Glu (n = 4) %). The frequency of the 27Glu allele was 29.5%. The group of adolescent carriers of the 27Glu allele of the ADRB2 gene presented higher mean adiposity indicators (abdominal circumference, trunk fat mass and visceral fat), as well as lower IL-10 concentrations when compared to non-carriers. Conclusions: The 27Glu allele was associated with adiposity indicators in overweight adolescents, while subcutaneous abdominal fat exhibited an inverse relationship with inflammatory variables and maximum oxygen uptake, which may result in more damage to health. Level of evidence III; Case-control study.

RESUMO Introdução: Estudos de associação entre a obesidade e fatores genéticos têm demonstrado a significativa contribuição de polimorfismos relacionados à distribuição de gordura corporal e processo inflamatório subclínico. Objetivo: Investigar a associação entre os genótipos do polimorfismo Gln27Glu do gene ADRB2 e indicadores de adiposidade, marcadores inflamatórios, parâmetros metabólicos e de aptidão física em adolescentes com excesso de peso. Métodos: Participaram 44 adolescentes, de ambos os sexos, com idade entre 13 e 17 anos, com diagnóstico clínico positivo de excesso de peso, divididos em dois grupos conforme os genótipos do polimorfismo Gln27Glu do gene ADRB2: a) Grupo de portadores do alelo 27Glu (Gln27Glu/Glu27Glu) (n=22); b) Grupo de não portadores do alelo 27Glu (Gln27Gln) (n=22). Ambos os grupos foram avaliados quanto à composição corporal, maturação sexual, variáveis de aptidão cardiorrespiratória e indicadores de força muscular. Foram dosados glicemia e insulina basais, perfil lipídico e perfil inflamatório. As adiposidades abdominais subcutânea e visceral foram avaliadas através de ultrassonografia. A genotipagem do polimorfismo Gln27Glu do gene ADRB2 foi realizada através do ensaio de discriminação alélica Taqman. Resultados: A frequência genotípica encontrada foi: Gln/Gln (n=22) (50,0%), Gln/Glu (n=18) (41,0%) e Glu/Glu (n=4) (9,0%). A frequência do alelo do 27Glu foi de 29,5%. O grupo de adolescentes portadores do alelo 27Glu do gene ADRB2 apresentou maiores médias de indicadores de adiposidade (circunferência abdominal, massa gorda troncular e gordura visceral), assim como menores concentrações de IL-10 quando comparados aos não portadores. Conclusões: O alelo 27Glu apresentou associação com os indicadores de adiposidade em adolescentes com excesso de peso, assim como a gordura abdominal subcutânea demonstrou relação inversa com as variáveis inflamatórias e o consumo máximo de oxigênio, podendo resultar em maiores prejuízos à saúde. Nível de evidência III; Estudo de caso-controle.

RESUMEN Introducción: Estudios de asociación entre la obesidad y factores genéticos han demostrado la significativa contribución de polimorfismos relacionados a la distribución de grasa corporal y proceso inflamatorio subclínico. Objetivo: Investigar la asociación entre los genotipos del polimorfismo Gln27Glu del gen ADRB2 e indicadores de adiposidad, marcadores inflamatorios, parámetros metabólicos y de aptitud física en adolescentes con exceso de peso. Métodos: Participaron 44 adolescentes, de ambos sexos, con edad entre 13 y 17 años, con diagnóstico clínico positivo de exceso de peso, divididos en dos grupos según los genotipos del polimorfismo Gln27Glu del gen ADRB2: a) Grupo de portadores del alelo 27Glu (Gln27Glu/Glu27Glu) (n = 22); b) Grupo de no portadores del alelo 27Glu (Gln27Gln) (n = 22). Ambos grupos fueron evaluados cuanto a la composición corporal, madurez sexual, variables de aptitud cardiorrespiratoria e indicadores de fuerza muscular. Fueron dosificadas glucemia e insulina basales, perfil lipídico y perfil inflamatorio. Las adiposidades abdominales subcutánea y visceral fueron evaluadas a través de ultrasonografía. El genotipado del polimorfismo Gln27Glu del gen ADRB2 fue realizado a través del ensayo de discriminación alélica Taqman. Resultados: La frecuencia genotípica encontrada fue: Gln/Gln (n = 22) (50,0%), Gln/Glu (n = 18) (41,0%) y Glu/Glu (n = 4) (9,0%). La frecuencia del alelo del 27Glu fue del 29,5%. El grupo de adolescentes portadores del alelo 27Glu del gen ADRB2 presentó mayores promedios de indicadores de adiposidad (circunferencia abdominal, masa grasa troncular y grasa visceral), así como menores concentraciones de IL-10, en comparación con los no portadores. Conclusiones: El alelo 27Glu presentó asociación con los indicadores de adiposidad en adolescentes con exceso de peso, así como la grasa abdominal subcutánea demostró relación inversa con las variables inflamatorias y el consumo máximo de oxígeno, lo que puede resultar en mayores perjuicios a la salud. Nivel de Evidencia III; Estudio de caso-control.

Adiposity and adipocytokines: the moderator role of cardiorespiratory fitness and pubertal stage in girls.

Background Cardiorespiratory fitness (CRF) and pubertal stages have been related to many health outcomes, including obesity and adipocytokines. Thus, the present study aimed to analyze the moderator role of CRF and pubertal stage in the relationship between adiposity and adipocytokines in girls. Method This cross-sectional study was performed with 42 pre-pubertal girls aged from 7 to 11 years and 54 post-pubertal girls aged from 13 to 17 years. Blood samples were collected to determine the serum levels of leptin and adiponectin, and then the leptin/adiponectin ratio (L/A ratio) was calculated. CRF, anthropometric and body composition indicators were assessed. For statistical analysis, descriptive statistics and several linear regression models were used. The moderation analysis was tested using the PROCESS macro. Results An interaction between body mass index (BMI) and CRF (ß: -0.70; confidence interval [CI]: -1.29, -0.12), as well as between BMI and pubertal stage (ß: 0.79; CI: 0.28, 1.30) with leptin, was found. Regarding the L/A ratio, an interaction was found only in BMI × CRF (ß: -0.56; CI: -1.06, -0.06). Using a combined interaction (CRF and pubertal stage), the results showed a positive association between BMI with leptin and L/A ratio only in low CRF, pre-pubertal and post-pubertal stages. Conclusion This study suggests a protective role of high levels of CRF in the relationship between BMI and adipocytokines. Despite the effect of pubertal stage, the results suggest that youth should be engaged in physical activity in order to improve CRF levels and consequently improve cardiometabolic health.