The main objective of this study is to evaluate the evolution of the sensitivity to insulin, a hormone that acts on sugar in the body, as well as other metabolic, motor and nutritional elements of children with cancer, according to the practice of intense physical activities or stretching. In view of the scientific work on this subject, it is expect to observe that the practice of intense physical activities will improve the results of the children in the metabolic, motor and nutritional evaluations, compared to the stretching program.

The protocol consists of 6 months of intense physical activity and stretching programs for children with solid cancer or haematological disease, starting at diagnosis. Evaluations will be performed at the first, third and sixth month of the programs and then six and eighteen months after they are stopped. The physical activity sessions will take place in the hospital during hospitalizations or by videoconference when the children are at home. The sessions are adapted to the needs, desires and abilities of the children and will take place two to three times a week. They will be mediated by various activities such as soccer, rugby, darts, muscle strengthening. Inclusion lasts two years.

Inclusion Criteria:

• age between 5 and 18 years old;
• have a solid cancer or hematological disease;
• be treated for the first time in pediatric oncology and hematology department;
• have an estimated life expectancy at diagnosis of more than 6 months.

Exclusion Criteria:

• present a physical and/or psychological impossibility to follow an adapted physical activity program;
• have a pre-existing heart disease that is not suitable for adapted physical activities;
• have a known type 1 diabetes
• have an obesity defined by a body mass index greater than or equal to the International Obesity Task Force 25 threshold