Exercise is a determinant of people’s well-being, and it contributes to the prevention and treatment of numerous diseases of affluence, e.g. diabetes and obesity. The rapid pace of economic development is affecting human functioning to such a degree that the need for physical activity, which has always been recognised as a biological and natural need, has been significantly reduced. Consequently, to-day public health related problems occurring globally are connected with the increasing incidence of cardiovascular, neoplastic, and met-abolic diseases. These problems are manifested not only in adults, but they also increasingly affect children and adolescents worldwide. In the case of children with type 1 diabetes, physical activity is of particular importance because it contributes to the child’s normal de-velopment and to positive effects of therapies. The paper discusses health-related benefits of physical activity in children and adolescents with type 1 diabetes, it presents recommendations related to physical activity published in Poland and abroad, and reviews contemporary methods of its assessment.