The glycemic response to ingested glucose for the treatment of hypoglycemia following exercise in type 1 diabetes patients has never been studied. Therefore, we aimed to characterize glucose dynamics during a standardized bout of hypoglycemia-inducing exercise and the subsequent hypoglycemia treatment with the oral ingestion of glucose. Ten male patients with type 1 diabetes performed a standardized bout of cycling exercise using an electrically braked ergometer at a target heart rate (THR) of 50% of the individual heart rate reserve, determined using the Karvonen equation. Exercise was terminated when hypoglycemia was reached, followed by immediate hypoglycemia treatment with the oral ingestion of 20 g of glucose. Arterialized blood glucose (ABG) levels were monitored at 5 min intervals during exercise and for 60 min during recovery. During exercise, ABG decreased at a mean rate of 0.11 ± 0.03 mmol/L·min-1 (minimum: 0.07, maximum: 0.17 mmol/L·min-1). During recovery, ABG increased at a mean rate of 0.13 ± 0.05 mmol/L·min-1 (minimum: 0.06, maximum: 0.19 mmol/L·min-1). Moreover, 20 g of glucose maintained recovery from hypoglycemia throughout the 60 min postexercise observation window.

Department of Internal Medicine 2nd Medical Faculty Charles University 150 00 Prague Czech Republic

Department of Internal Medicine 3rd Faculty of Medicine University Hospital Královské Vinohrady 106 00 Prague Czech Republic

Department of Pathophysiology 3rd Faculty of Medicine Charles University 106 00 Prague Czech Republic

Faculty of Medicine Josip Juraj Strossmayer University of Osijek 310 00 Osijek Croatia

Institute of Computer Science Academy of Science of the Czech Republic 110 00 Prague Czech Republic

School of Food Science and Nutrition University of Leeds Leeds LS2 9JT UK

School of Medicine University of Zagreb 100 00 Zagreb Croatia

Vuk Vrhovac University Clinic for Diabetes Endocrinology and Metabolic Diseases Merkur University Hospital 100 00 Zagreb Croatia

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