Hormonal response during physical exercise of different intensities in adolescents with type 1 diabetes and healthy controls

Background Physical activity is a critical component in the care of diabetes. Although it offers health benefits it presents challenges. Objective To investigate differences between adolescent boys and girls with type 1 diabetes and healthy controls in terms of maximal work capacity (VO2 max) and hormonal response to physical exercise of different intensities. Subjects Twelve individuals (six boys and six girls; age 1419 yr, pubertal stage 45) with type 1 diabetes (duration, 6.3 +/- 4.4 yr; hemoglobin A1c, 63 +/- 10 mmol/mol) were compared with 12 healthy controls matched for age, sex, pubertal stage, body mass index standard deviation score, and amount of regular physical activity. Methods During consecutive days, three different workloads; maximal, endurance, and interval, were performed on an Ergometer cycle. During the tests, levels of lactate, glucose, insulin, and regulatory hormones [glucagon, cortisol, growth hormone (GH), adrenaline, and noradrenaline] were measured in blood. Subcutaneous glucose was measured continuously. Results VO2 max did not differ between the groups, diabetes 49.8 +/- 9.9 vs. control 50.7 +/- 12.0 mL/min/kg. Hormonal responses did not differ between the groups except for mean peak GH level during the interval test, diabetes 63.2 +/- 27.0 vs. control 33.8 +/- 20.9 mU/L, p < 0.05. Conclusions Physical capacity and hormonal regulation of blood glucose in connection with physical exercise of different intensities did not differ between adolescents with diabetes and healthy controls. Thus, adolescents with type 1 diabetes can participate in physical activity on the same terms as healthy peers.