Molecular mechanisms in obesity and intensive training in children

• Autor(a) principal: Fernandes, Raquel Alexandra Rodrigues
• Data de Publicação: 2016
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10773/22363
• topic: Obesidade - Crianças; Exercício físico

Physical inactivity is a major risk for obesity. This chronic disease results from a caloric imbalance causing an enlargement of adipocytes by excessive fat storage. With an increasing prevalence, childhood obesity is correlated with endothelial dysfunction, inflammation and oxidative stress conducting to the development of other diseases not only in children but also during adulthood. In other hand, numerous children practice exercise of high duration or intensity in high competition sports, which can have harmful effects at physical, physiological and psychological level. In high competition young athletes, oxidative stress and immunosuppression can happen leading to an elevated risk of infection. However, an improved lipid profile is found in childhood athletes. Thus, the objective of the present study was to analyze the impact of childhood obesity as well as intense swimming training in body composition, inflammation and lipid profile, through blood analysis, bioimpedance and immunodetection of the pro-inflammatory cytokines (IL-6 and TWEAK), a myokine (Myostatin) and an acute-phase protein (CRP). For that, 24 young people were recruited into three groups: obese, athlete and lean. The obese group had high levels of body fat, an atypical lipid profile (low HDL and high LDL), high levels of lactate dehydrogenase in the blood indicating tissue damage, chronic inflammation (high IL-6, CRP and TWEAK) and low muscle mass (high Myostatin) without muscle damage (low CK). However, low serum levels of hepatic enzyme (AST and ALT) in these obese children do not associate obesity with liver disease. In other hand, intense physical exercise is not a harmfull activity for young athletes, since the lipid profile is improved and the increased levels of inflammatory markers is not significant. The main benefit of intensive training is the decreased levels of glucose being a protective role for diabetes.