Obesity and asthma are both major public health concerns, since their prevalence is increasing worldwide. All current studies show that there is a low-grade systemic inflammation in both asthmatic and obese subjects.Asthma is the first chronic pathology in children. Despite recommendations, asthma control, treatment and follow-up remain insufficient, especially in obese children.Non-control varies according to BMI and is more frequent in obese children. Obesity makes it difficult to manage severe asthma. Similarly, severe asthma can promote weight gain due to systemic corticosteroid use.The effectiveness of physical activity on asthma control is greater the more severe the asthma. Weight loss significantly improves asthma severity and the integration of moderate to intense physical activity should be systematic in the therapeutic strategy of overweight or obese asthmatic children and adolescents.