Intravenous glucose tolerance test-derived glucose effectiveness in physically trained humans

Area of Science:

• Exercise Physiology
• Metabolic Studies
• Human Physiology

Background:

• Regular physical activity is known to influence glucose metabolism.
• Understanding the specific effects of training on glucose effectiveness and insulin sensitivity is crucial for metabolic health.
• Sedentary lifestyles are associated with impaired glucose regulation.

Purpose of the Study:

• To quantify glucose effectiveness (SG) and insulin sensitivity in physically trained versus sedentary males.
• To determine the duration of these metabolic improvements after cessation of training.

Main Methods:

• Utilized the minimal model approach to estimate SG and insulin sensitivity.
• Administered intravenous glucose and infused insulin to assess metabolic response.
• Studied trained subjects (high aerobic capacity) 16 hours and 1 week post-training.

Main Results:

• Trained subjects demonstrated significantly higher glucose disappearance rates, indicating better glucose tolerance.
• Insulin sensitivity was markedly elevated in trained individuals compared to sedentary controls.
• Glucose effectiveness (SG), reflecting glucose's role in uptake and hepatic suppression, was significantly greater in trained males.

Conclusions:

• Physical training substantially enhances both glucose effectiveness and insulin sensitivity in males.
• These metabolic benefits of exercise training are sustained for at least one week after the last training session.
• Findings underscore the importance of regular physical activity for maintaining optimal glucose homeostasis.