Changes in Individual Glucose Threshold during Military Training

Abstract

The objective of the present study was to assess any improvement in the IGT (Individual Glucose Threshold) of soldiers during military physical training (MPT). Nine healthy non-athlete recruits (mean weight: 66.3±7.9 kg; mean height: 1.77±0.05 cm; mean age: 18.4±0.5 year) were submitted to incremental ergometric test on a treadmill. The initial speed was 6.0 km.h⁻¹ followed by increment of 1.0 km.h⁻¹ every 2 min until the subject became exhausted. Between running stages, a 15 s pause allowed 5 μL of capillary blood sample to be collected from the earlobe for glucose analysis. The IGT was determined by blood glucose concentration ([Gluc]) kinetics considering the exercise intensity corresponding to the lower [Gluc] during the test. The tests were conducted in four steps: before and after exactly 30, 60, and 90 days of training. The results showed that IGT was initially detected at 9.4±1.8 km.h⁻¹ but shifted to 11.4±1.9, 11.2±2.1 and 11.9±1.4 at 30, 60, and 90 days of training, respectively. A significant improvement after 30 and 90 days of training (p<0.05) compared to baseline. We concluded that the IGT shifted to higher exercise intensities after MPT. Future studies examining different training modalities are required to verify our results.

Key words

minimum glucose levels - performance index - anaerobic threshold - sensitivity

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