Influence of magnitude of weight loss on Adipo/lep ratio in adolescents with obesity undergoing multicomponent therapy.

BACKGROUND AND AIMS: The expansion of adipose tissue increases leptin secretion associated with a reduction of adiponectin concentration, which negatively affects health of adolescents with obesity. This study aims to investigate the effects of non-intensive interdisciplinary therapy on cardiometabolic parameters including leptin, adiponectin and adiponectin/leptin ratio as a dependent manner on its magnitude of weight loss reduction. METHODS AND RESULTS: Thirty-eight adolescents (14-19 y.o) were enrolled in an interdisciplinary therapy for 20 weeks. Body composition, biochemical parameters, leptin and adiponectin were measured at baseline and after therapy. The adolescents were divided into two groups according to the magnitude of total weight loss, less than 5% (<5%-n = 18) or greater than or equal to 5% (≥5%-n = 20). Leptin decreased in whole group after therapy, while adiponectin, and adiponectin/leptin ratio increased. Additionally, body composition was improved. Only the group who lost ≥5% of body weight could reduce the inflammatory state. CONCLUSION: The interdisciplinary therapy contributes to improve cardiometabolic parameters that could be involved on inflammation in adolescents with obesity, this improvement occurred mainly when the weight loss is ≥5% of body weight. It could be a target for control the inflammatory process related to obesity in adolescents.

The effect of aerobic plus resistance training associated with a long-term interdisciplinary weight loss program on visceral fat and isokinetic parameters in adolescents with obesity.

BACKGROUND: Obesity can lead to a number of alterations in biomechanical structures. We aimed to assess the effect of aerobic plus resistance training associated with an interdisciplinary approach on visceral fat and isokinetic parameters in a long-term weight loss therapy program. METHODS: Forty-four postpubertal obese adolescents were involved in the 1-year interdisciplinary weight loss therapy program (clinical, nutritional, psychological and physical training). Body composition, and visceral and subcutaneous fat were measured by DXA absorptiometry and ultrasonography, respectively. Peak torque was analyzed using an isokinetic dynamometer. Statistical analysis was performed using t-tests to assess the effect of the intervention. RESULTS: There was a significant reduction in body fat with an inverse increase in lean mass. Positive correlations were observed between peak torque and lean body mass and negative correlations with visceral fat, gynoid fat mass, arm fat mass and subcutaneous fat. CONCLUSIONS: An interdisciplinary weight loss program can reduce body fat and increase peak torque and improve muscle strength. The results reinforce the importance of this kind of approach to treat obesity and improve the quality of life in this population.

Homeostasis Model Assessment-Adiponectin: the role of different types of physical exercise in obese adolescents.

BACKGROUND: Homeostasis Model Assessment-Adiponectin (HOMA-AD) is suggesting a new biomarker of insulin resistance in obese population. In this way, the purpose of this study was to investigate the effects of different kinds of exercise in the sensitive index predictor of insulin resistance. METHODS: A total of 148 obese adolescents were enrolled in the program. They aged 15-19 y, with Body Mass Index (BMI) ≥P95th and were submitted to 1 year of interdisciplinary weight loss therapy, randomized in two groups, aerobic training (AT) (N.=51) and aerobic plus resistance training (N.=97). Blood samples were collected to analyze adiponectin, glucose and insulin concentrations. The insulin resistance was measured by HOMA-AD and Homeostasis Model Assessment Insulin Resistance Index (HOMA-IR). RESULTS: Both kinds of exercise training promoted a decrease in body mass, body mass index, fat mass, visceral and subcutaneous fat. However, only aerobic plus resistance training was effective to reduce HOMA-AD, insulin and glucose concentration; and increase insulin sensibility and adiponectin concentration. CONCLUSIONS: The aerobic plus resistance training was more effective than AT alone to improve the HOMA-AD, suggesting clinical application on obesity, diabetes, atherosclerosis and metabolic syndrome control in the pediatric population.

Influence of glycemic index and glycemic load of the diet on the risk of overweight and adiposity in childhood. / Influência do índice glicêmico e carga glicêmica da dieta sobre o risco de sobrepeso e adiposidade na infância.

OBJECTIVE: To investigate the association between the glycemic index and the glycemic load of the diet with the risk of overweight and high adiposity in children with 5 years of age. METHODS: Cross-sectional study nested in a cohort of 232 children born and living in Diamantina (MG, Brazil). Parents and/or guardians provided the food intake data, using a semiquantitative food frequency questionnaire, past history and socioeconomic conditions. Anthropometric and fatness data were collected from the children. The dietary glycemic index and the glycemic load were calculated from the food intake. The glycemic index and glycemic load effect on overweight and adiposity in children was assessed by the Poisson regression (p<0.05). RESULTS: The prevalence of overweight by body mass index was 17.3%, and high adiposity was observed in 3.4% and 6.9% by triceps skinfold and subscapular skinfold, respectively. No difference was reported between the mean body mass index, triceps skinfold and subscapular skinfold according to the glycemic index and glycemic load tertiles; however, the overweight group presented a higher carbohydrate intake (p=0.04). No association was found between glycemic index and glycemic load with overweight and adiposity among the children assessed. CONCLUSIONS: The glycemic index and glycemic load of the diet were not identified as risk factors for overweight and adiposity in this cross-sectional study.