From the Research
Glucose spikes during extreme exercise in non-diabetic individuals are primarily caused by the body's natural stress response, which is a normal and healthy adaptive mechanism to meet increased energy demands during strenuous physical activity. During intense physical activity, the body releases stress hormones like adrenaline, noradrenaline, and cortisol, which signal the liver to rapidly release stored glucose (glycogen) into the bloodstream to provide immediate energy for working muscles. Additionally, extreme exercise can temporarily decrease insulin sensitivity, meaning cells don't absorb glucose as efficiently, further contributing to elevated blood glucose levels.
This physiological response is supported by studies such as 1, which highlights the unique effects of intense exercise on glucose regulation, including a seven- to eightfold increase in glucose production and a three- to fourfold increase in glucose utilization. The study also notes that the marked catecholamine responses to intense exercise are responsible for both the glucose production increment and the restrained increase of glucose utilization.
Other studies, such as 2, also demonstrate the impact of exercise on glucose metabolism in individuals with type 2 diabetes, showing that exercise can improve glucose clearance in muscle and reduce hyperglycemia. However, the most relevant study to this question is 1, as it specifically addresses the effects of intense exercise on glucose regulation in a population that includes non-diabetic individuals.
The key points to consider are:
- The body's natural stress response to extreme exercise causes glucose spikes
- Stress hormones like adrenaline, noradrenaline, and cortisol signal the liver to release stored glucose into the bloodstream
- Temporary decreases in insulin sensitivity contribute to elevated blood glucose levels
- This physiological response is normal and healthy, and no intervention is needed for non-diabetic individuals.
Overall, the current evidence suggests that glucose spikes during extreme exercise in non-diabetic individuals are a normal response to physical activity, and no intervention is necessary.