You've probably heard that exercise is good for your health. But what effect does it have on your blood sugar levels? Does the blood sugar level fall or does it rise? And what does that mean?
It may surprise you, but both are true.
Understanding why and when things happen is an important part of health management.
How are sport and blood sugar related?
Exactly how exercise changes blood glucose levels can be different for each person. Some notice major effects, while others may only notice small changes in their blood glucose curves.
In general, the change in blood glucose levels (up or down) depends on the type, duration and intensity of exercise, as well as your diet and overall health. So the relationship between blood sugar and exercise is complex.
The best way to understand the relationship between exercise and blood sugar is to look directly at the science. So let's take a look at a blood glucose curve.
When you exercise, your body relies on two fuel sources: Glucose and fat. So how your blood sugar changes during exercise depends on the intensity of your workout and the fuel source your body uses.
Which sports influence the blood sugar level?
Light endurance exercises such as yoga, light jogging, or quiet swimming do not require quick bursts of energy. In these cases, the body gets more energy from fat, so your blood sugar level usually stays the same or drops.
During high-intensity exercise (like HIIT, interval training, or strength training), your body doesn't have the energy stores to support your workout. Therefore, it provides glucose from storage to keep your workout well energized right away. This extra boost of glucose results in a sharp rise in blood glucose levels.
So, should you avoid blood sugar spikes while exercising?
The sudden spike in blood sugar during high-intensity exercise may worry you, but it doesn't have to. The acute rise in blood sugar during high-intensity exercise is a completely different physiological response than eating a cookie spikes blood sugar levels. The rise in blood sugar during strenuous exercise improves both fasting blood sugar and insulin sensitivity over time. These adjustments support your metabolic health and blood sugar management.
By continuously measuring your blood glucose levels before, during and after exercise, you can analyze your body's response. Seeing how your blood glucose level changes during exercise will help you find the right workout for your situation and achieve your health goals.
