From the Guidelines
Blood glucose can increase after a workout due to the body's stress response, as stated in the most recent study 1, which highlights the importance of monitoring blood glucose levels during and after exercise. During exercise, especially high-intensity workouts, the body releases stress hormones like adrenaline and cortisol, which trigger the liver to release stored glucose into the bloodstream to provide energy for working muscles.
- Additionally, intense exercise can cause muscle breakdown, releasing amino acids that the liver converts to glucose through gluconeogenesis.
- This glucose spike is typically temporary and part of the body's normal adaptation to physical stress.
- For most people, this increase is beneficial as it helps maintain energy levels during and immediately after exercise. However, people with diabetes should monitor their blood glucose levels when exercising and may need to adjust their medication or carbohydrate intake accordingly, as suggested by 1, which emphasizes the need for individualized care and education on managing blood glucose levels during exercise. The post-exercise glucose elevation usually resolves within 1-2 hours as the body recovers and insulin sensitivity improves, and regular exercise actually helps improve long-term blood glucose control by enhancing insulin sensitivity in muscle tissues, as supported by the latest guidelines 1.
From the Research
Blood Glucose Levels After Workout
- Blood glucose levels can increase after a workout due to various physiological responses, including the release of glucose-raising endocrine hormones and the breakdown of liver glycogen 2, 3.
- During prolonged exercise, the body increases glucose uptake in working skeletal muscle, which can lead to an increase in blood glucose levels 3.
- However, the body also has mechanisms to maintain blood glucose homeostasis, such as the stimulation of liver glycogen breakdown and the synthesis of glucose from other substances 3.
Factors Affecting Blood Glucose Levels
- Exercise intensity and duration can impact blood glucose levels, with more intense and longer-duration exercise leading to greater increases in blood glucose 2, 3.
- Training status and visceral fat levels can also affect blood glucose levels, with more trained individuals and those with lower visceral fat levels tend to have better glucose control 2.
- Nutrition and timing of meals around exercise can also impact blood glucose levels, with carbohydrate-rich diets and intake before and during exercise showing benefits for athletic performance and glucose control 4, 5.
Importance of Physical Activity for Glucose Control
- Regular physical activity can improve glucose control and reduce the risk of complications associated with diabetes 2, 6.
- Physical activity can improve insulin sensitivity and glucose uptake in skeletal muscle, leading to better blood glucose control 2, 3.
- A systematic review and meta-analysis found that physical activity was associated with improved glucose control in diabetes patients, with physically active patients having controlled their blood glucose levels by 2.4 times compared to their counterparts 6.