The Effect of Hyperglycaemia on Local Energy Stores in the Working Muscle in Patients With Type 1 Diabetes Mellitus

Inclusion Criteria: * Male * Aged from 20 to 40 years * Patients with type 1 diabetes mellitus lasting for at least 5 years (C-Peptide ≤ 0.3 nmol/l in the presence of a plasma glucose level ≥ 7 mmol/L, indicating insulin dependence) * Insulin delivery by CSII (continuous subcutaneous insulin infusion) for at least 6 months * Acceptable to good metabolic control, reflected by an HbA1c 5-8% * Normal insulin sensitivity, reflected by a daily insulin requirement of 0.3-1.0 U/kg body weight * minimum 30' of moderate exercise 3 times per week * BMI in the range of 18-25 kg/m2 Exclusion Criteria: * Chronic complications of diabetes: * Microalbuminuria (Mogensen nephropathy stadium ≥ III) * Sensory neuropathy (vibration better than 5/8 at the metatarsophalangeal articulation of digitus I) * Proliferating retinopathy * No history of macro-vascular complications * Clinically relevant autonomous neuropathy * Smoking * Abnormal thyroid function * Major depression, psychosis and other severe personality disorders, claustrophobia * Active neoplasia * Contraindications to exposure to a 1.5 T magnetic field (pace-makers, osteosynthetic material, etc.) * Abnormal liver or renal function (creatinine \> 130 µmol/L; ASAT and ALAT \> 3 times the upper reference limit) * Excessive alcohol consumption (\>60g/d) or drug-abuse * Refusal to give written informed consent * Participation in another study * Patients, who are not suitable for the study according to the study physician