Glucose Pulse
A simple method to estimate the amount of glucose oxidized during exercise in type 1 diabetic patients
- Maria Pia Francescato, MD12,
- Luigi Cattin, MD3,
- Mario Geat, MD3,
- Elena Tosoratti, MD12,
- Stefano Lazzer, PHD12,
- Claudio Noacco, MD4 and
- Pietro Enrico di Prampero, MD12
- 1Department of Biomedical Sciences and Technologies, University of Udine, Udine, Italy
- 2M.A.T.I. Centre of Excellence, University of Udine, Udine, Italy
- 3Department of Clinical, Morphological and Technological Sciences, University of Trieste, Trieste, Italy
- 4Diabetologic Unit, Hospital S. Maria della Misericordia, Udine, Italy
- Address correspondence and reprint requests to Maria Pia Francescato, Department of Biomedical Sciences and Technologies, University of Udine, P.le Kolbe 4, 33100 - UDINE, ITALY. E-mail: mfrancescato{at}mail.dstb.uniud.it
In type 1 diabetic patients, exercise contributes to enhance insulin sensitivity (1,2) and may help, together with diet and insulin therapy, to achieve and maintain better metabolic control (3,4). However, lack of insulin regulation during exercise leads to frequent metabolic imbalances (5). Fat and carbohydrates are the main substrates for energy production in skeletal muscle during aerobic exercise in well-fed humans (6), with their relative contribution to total energy production being a function of exercise intensity (7–10). Below the anaerobic threshold, both oxygen consumption and heart rate during exercise increase linearly as a function of exercise intensity (6). On the basis of these relationships, the aim of the present study was to verify the possibility of using heart rate to estimate the amount of glucose oxidized during exercise in type 1 diabetic patients as well as in a control group of healthy subjects.
RESEARCH DESIGN AND METHODS
Fifteen type 1 diabetic patients (9 men, 6 women, HbA1c [A1C] 6 ± 1.2%, reference values 4–6%) (11) aged 18–45 years (average 38 ± 6) and 15 healthy subjects (9 men, 6 women, 34 ± 7 years) gave their voluntary consent to participate after being informed on the nature, purpose, and possible risks. Duration of diabetes and mean insulin dose were 17 ± 8 years and 0.52 ± 0.1 IU · kg−1 · day−1, respectively. Average body weight and height were 71 ± 9 kg and 175 ± 9 cm in diabetic patients vs. 70 ± 9 kg and …
