nowadays, juvenile obesity and physical inactivity are pandemic conditions which relate to a greater future risk of cardiovascular diseases. from an inflammatory point of view, they have attracted massive scientific attention. the beginning of the events related to atherosclerosis may occur in childhood, generating endothelial and metabolic dysfunction; however, the symptoms usually only appear later on, in adulthood. the fat tissue is recognized as being metabolically active, stimulating the production of inflammatory cytokines, such as the tumoral necrosis factor, interleukines 1, 6 and 10, c-reactive protein, among others. there is plenty of evidence that the serum levels of these citokines are higher in overweight individuals, including children and adolescents. early prevention as young as possible is the best way to avoid future consequences of obesity. in this context, the potential benefits of regular physical exercise have been surprising. researchers have shown evidence of anti-inflammatory responses, including lower levels of interleukine 6, c-reactive protein, leptin, besides higher levels of adiponectins after engagement in regular physical activity. however, we still have few controlled randomized studies addressing the relations between obesity, inflammation and exercise for the pediatric population. there are controversial findings in this field, and many of them come from adult studies. thus, the purpose of the present review is to evaluate the metabolic role of physical exercise in juvenile obesity, aiming at heart protection.