Your body's glycaemic balance depends on the following 2 factors:
- How quickly meal-derived glucose arrives in the blood (what type of meal you eat) and,
- The rate at which exercise draws upon this fuel.
Point 2 above is extremely important to keep in mind. Reducing insulin secretion in response to glucose rises after meals is a good thing, as we want to keep insulin levels under control if we are to remain healthy (and at our desired weight).
When you exercise your muscle membranes become more efficient at absorbing glucose, your heart pumps more glucose-containing blood to your muscles, and chemical enzymes change to help glucose transport even more. Our muscle cells get the glucose they need to fuel a workout, and our blood glucose levels drop.
Put simply – when you exercise your body releases more glucose into your muscle cells, and your blood glucose levels drop.
Exercise can boost glucose uptake by up to 50 times
compared to when we are sedentary after a meal.
So when is the ideal time to exercise after eating?
- If you’re having a smoothie for breakfast or lunch, or fast-absorbing carbohydrates (fruit, starchy foods, or anything processed like foods containing sugar or refined flour), you may want to get moving straight away.
- For most other meals - A 2016 review examined 39 papers, encompassing a collective 615 participants with various metabolic conditions (such as diabetes, prediabetes, and obesity) and people without any diagnosed conditions. The study came to the conclusion that exercising 30 to 45 minutes after eating is the ideal time to curb glucose levels.
But how long do you need to exercise for?
In a 2021 review of 51 studies published in Sports Medicine, 30 minutes of continuous cardio (brisk walk, cycle, light jog) within 6 hours of eating decreased glucose and insulin levels in the six hours after a meal (the postprandial period) compared to being at rest.
So in summary - whenever possible, move your body after eating to mobilize post-meal glucose to fuel physical activity and curb the spike you might experience if you were inactive. If you make a habit of doing this (and especially straight after a carb laden meal) you will be healthier and leaner over time.