Abstract

Introduction: Physical exercise in the fasting state has been a controversial topic; however, some studies have shown a greater loss of body fat and better glycemic control in those who participate in aerobic training when fasting.
Aim: To evaluate the glycemic response after a session of moderate or vigorous physical exercise in young women in the state of fasting.
Material and method: A randomized clinical trial was carried out. Twenty-six women (19 to 22 years old) were randomly assigned to two intervention groups. The first group was trained at an intensity of 70% of maximum heart rate (MHR) for 30 minutes, and the second group at an intensity of 90% MHR for 15 minutes. Height (cm), weight (Kg), body mass index (BMI), fat percentage, and maximum oxygen consumption (VO2max) during a stress test were evaluated. Blood glucose levels were checked before and after the exercise session of each group.
Results: No significant changes were found in post-exercise blood glucose levels in any experimental group, and the existing differences were not statistically significant.
Conclusions: Moderate or vigorous physical exercise during fasting did not show significant variations in blood glucose, which suggests that it is safe for healthy young women to train when fasting.
Key words: Exercise. Blood glucose. Athletic performance. Body composition.