In order to obtain suitable exercise intervention model for children and adolescents with obese or metabolic syndrome in China, we conduct a RCT to examine the effects of different intensity exercise intervention on weight, and other cardiometabolic risk factors among children and adolescents, we also test the effects of exercise interventions on multi-omics such as metabolomics, gut microbiome, genetics, and explore the potential mechanisms by which exercise interventions modulate cardiometabolic risk. This is a randomized controlled study. Children and adolescents with obesity or metabolic syndrome were randomly divided into three groups, including low intensity exercise training group, moderate and intermittent high intensity exercise training group. The investigators will obtain organ hydrodynamics indexes by abdominal ultrasound and computational fluid dynamics technology, and obtain the metabolic regulation mechanism of the body in response to exercise through the detection of metabolism related small molecules in blood and urine and the analysis of intestinal flora, so as to explore the potential value and mechanism of different exercise modes in the treatment of obesity and metabolic syndrome. At the same time, the behavior and self-consciousness of children and adolescents will be investigated to obtain the suitable exercise intervention model for Chinese children and adolescents with obesity and metabolic syndrome. In conclusion, this study aims to demonstrate which exercise mode can alleviate obesity or reverse metabolic diseases, analyze which factors can sense exercise, and explore the potential mechanisms through mutil-omic approach, so as to improve metabolic syndrome.