The incidence of childhood obesity is increasing, followed by metabolic diseases related to overweight and obesity in children. High intensity interval training (HIIT) has recently been shown to improve the body composition and cardiovascular health of obese children. Currently, there is little evidence on the impact of exercise intensity on endocrine and metabolic indicators and quality of life in obese children.

The main purpose of this study is to compare the effects of short-term supervised high-intensity interval training and moderate intensity continuous training (MICT) on metabolic indicators in obese children under an energy limited balanced diet. A multicenter prospective randomized controlled trial was conducted on 388 obese children in South China. The experimental group will be randomly assigned to (1) HIIT and energy limited balanced diet, and (2) MICT and energy limited balanced diet. The experimental group will participate in a 3-month (supervised) exercise training. The measurement of the study endpoint will be followed up at baseline, 3 months (after supervised intervention), 9 months, and 1 year. The primary endpoint is the percentage of weight loss (△ Wt%). Secondary endpoints include waist to height ratio, body mass index (BMI), body fat percentage, insulin resistance index (HOMA-IR), insulin secretion index (ISI), and Δ HtSDSBA. The results of this study will generate a wealth of information on the impact of exercise intensity on weight loss and endocrine metabolism in obese children, and develop more effective evidence-based exercise prescription guidelines in this population.

Inclusion Criteria:

1. The guardian understands and signs the informed consent. If the subject is at least 8 years old, the informed consent must be signed.
2. Age 6~16 years old, male and female;
3. BMI≥ "sex-age BMI reference point for obesity screening of school-age children aged 6-18 years";
4. no disability;
5. Joint cardiopulmonary function assessment showed that participation was safe;
6. At least one year of follow-up is expected.

Exclusion Criteria:

1. Have high blood pressure (defined as systolic or diastolic blood pressure values above the 95th percentile), any history or evidence of heart disease and/or abnormal resting or stress echocardiography or a combined cardiopulmonary function assessment indicating that participation is not safe;
2. have any chronic disease, such as chronic asthma, kidney disease, type 1 diabetes, epilepsy, etc.;
3. suffering from organic diseases, such as ovarian tumors, hamartoma, etc.;
4. A smoking habit or orthopedic/neurological condition that may limit exercise ability;
5. Confirmed attention deficit hyperactivity disorder and steroid use.