Validation of Algorithms for Basal Insulin Rate Reductions in Type 1 Diabetic Patients Practising Physical Activity

Primary aim: To show that in subjects with type 1 diabetes with a subcutaneous continuous insulin infusion, adjustment of the recommended basal insulin flow rate in the event of physical activity allows the subjects to practice sports without any increase in incidence of hypoglycaemia during physical activity or the ensuing hours. (NB: hypoglycaemia is defined as blood glucose less than 3 mmol/l or 0,54 g/l in accordance with the EMEA definition). The proposed algorithms consist of a temporary reduction in basal flow of 50 percent or 80 percent (temporary basal flow TBR50 or TBR80) depending on the intensity of physical activity (50 percent of VO2max or 75 percent of VO2max). Switching off the pump will also be studied as an option to adjust insulin dosage in the event of unprogrammed physical activity (temporary reduction of basal flow by 100 percent). Secondary aims: * Characterisation of hypoglycaemia during and after physical activity based on CGMS data: symptomatic or non-symptomatic nature of hypoglycaemia, time to onset of hypoglycaemia in relation to the start of physical activity, degree and severity of hypoglycaemia. * Evaluation of overall variations in blood glucose in the event of physical activity using CGMS data (area under the curve). * Evaluation of glucose restoration methods used in the event of hypoglycaemia. * Analysis of subgroups of patients with and without hypoglycaemia.