BackgroundThe prevalence of obesity in pediatric population is increasing at an accelerated rate in many countries, and has become a major public health concern. Physical activity, particularly exercise training, remains to be a cornerstone of pediatric obesity interventions. The purpose of our current randomized intervention trial was to compare the effects of two types of training matched for training volume, aerobic and concurrent, on body composition and metabolic profile in obese adolescents. Thus the aim of the study was compare the effects of two types of training matched for training volume, aerobic and concurrent, on body composition and metabolic profile in obese adolescents.Methods32 obese adolescents participated in two randomized training groups, concurrent or aerobic, for 20 weeks (50 mins x 3 per week, supervised), and were compared to a 16-subject control group. We measured the percentage body fat (%BF, primary outcome), fat-free mass, percentage of android fat by dual energy x-ray absorptiometry, and others metabolic profiles at baseline and after interventions, and compared them between groups using the Intent-to-treat design.ResultsIn 20 weeks, both exercise training groups significantly reduced %BF by 2.9-3.6 % as compare to no change in the control group (p = 0.042). There were also positive changes in lipid levels in exercise groups. No noticeable changes were found between aerobic and concurrent training groups.ConclusionsThe benefits of exercise in reducing body fat and metabolic risk profiles can be achieved by performing either type of training in obese adolescents.Trial registrationRegistration number: RBR-4HN597.

Dyslipidemia (high concentrations of LDL-c and low concentrations of HDL-c) is a major cause of cardiovascular events, which are the leading cause of death in the world. On the other hand, nutrition and regular exercise can be an interesting strategy to modulate lipid profile, acting as prevention or treatment, inhibiting the risk of diseases due to its anti-inflammatory and anti-atherogenic characteristics. Additionally, the possibility of controlling different training variables, such as type, intensity and recovery interval, can be used to maximize the benefits of exercise in promoting cardiovascular health. However, the mechanisms by which exercise and nutrients act in the regulation of cholesterol and its fractions, such as reverse cholesterol transport, receptors and transcription factors involved, such as PPARs and their role related to exercise, deserve further discussion. Therefore, the objective of this review is to debate about non-medical approaches to increase HDL-c, such as nutritional and training strategies, and to discuss the central mechanisms involved in the modulation of lipid profile during exercise, as well as that can be controlled by physical trainers or sports specialists in attempt to maximize the benefits promoted by exercise. The search for papers was performed in the databases: Medline (Pubmed), Science Direct, Scopus, Sport Discus, Web of Science, Scielo and Lilacs until February 2016.

Obesity is a risk factor able to trigger several inflammatory alterations and the imbalance between pro- and anti-inflammatory cytokine productions. Physical exercise is an important strategy for reduction of inflammatory established process. The aim of this study was to evaluate the effect of 16 weeks of three exercise training programs in the inflammatory profile and insulin resistance in overweight/obesity. Thirty two men and women (46.4±10.1 years; 162.0±9.1 cm; 82.0±13.6 kg) were divided into three groups for training on a treadmill: continuous at 70% maximum heart rate (HRmax) 5 times a week (CONT); 1×4 min (1-bout) and 4×4 min (high intensity interval training, HIIT) at 90% HRmax 3 times a week. Interleukin (IL) 6 and IL-10, tumor necrosis factor-alpha (TNF-α), insulin and adiponectin levels were analyzed by enzyme-linked immunosorbent assay, and homeostasis model assessment insulin resistance was calculated. After 16 weeks of training blood concentrations of IL-6 decreased in the HIIT group (P=0.035), TNF-α decreased in the CONT (P=0.037) and increased in HIIT (P=0.001) and adiponectin decreased in the three training models. There was a trend towards decreased body weight and body mass index (BMI) after HIIT only (P=0.059 and P=0.060, respectively). Despite the decrease of adiponectin and the increase of TNF-α in HIIT group, insulin sensitivity showed a trend for improvement (P=0.08). HIIT program decreased IL-6 at rest and although not significant was the only who tended to decrease total body weight and BMI. Taken together, our data suggest that both HIIT as well as CONT exercises training program promotes changes in inflammatory profile in overweight/obesity, but dissimilar response is seen in TNF-α levels.

BackgroundPrevious studies have shown an association between adiposity, especially intra-abdominal adipose tissue, and hemodynamic/metabolic comorbidities in adults, however it is not clear in pediatric population. The aim of the study was to analyze the relationship between non-alcoholic fatty liver disease (NAFLD) and components of metabolic syndrome (MS) with values of intra-abdominal (IAAT) and subcutaneous (SCAT) adipose tissue in obese children and adolescents.MethodsCross-sectional study. Subjects: 182 obese sedentary children and adolescents (aged 6 to 16 y), identified by the body mass index (BMI). Measurements: Body composition and trunk fat by dual-energy X-ray absorptiometry- DXA; lipid profile, blood pressure and pubertal stage were also assessed. NAFLD was classified as absent (0), mild (1), moderate (2) and severe (3), and intra-abdominal and subcutaneous abdominal fat thickness were identified by ultrasound. The MS was identified according to the cut offs proposed by World Health Organization adapted for children and adolescents. The chi-square test was used to compare categorical variables, and the binary logistic regression indicated the magnitude of the associations adjusted by potential cofounders (sex, age, maturation, NAFLD and HOMA-IR).ResultsHigher quartile of SCAT was associated with elevated blood pressure (p = 0.015), but not associated with NAFLD (p = 0.665). Higher IAAT was positively associated with increased dyslipidemia (p = 0.001), MS (p = 0.013) and NAFLD (p = 0.005). Intermediate (p = 0.007) and highest (p = 0.001) quartile of IAAT were also associated with dyslipidemia, independently of age, sex, maturation, NAFLD and HOMA-IR (homeostatic model assessment-insulin resistance).ConclusionObese children and adolescents, with higher IAAT are more prone to develop MS and NAFLD than those with higher values of SCAT, independent of possible confounding variables.