There are so many good reasons to exercise. In the meantime, doctors even write prescriptions for it. It's not surprising, then, that exercise also affects your blood sugar levels, but your blood sugar levels also affect your response to exercise. In this article, you'll learn:
- How sport and blood sugar are linked
- What types of workouts raise and lower your blood sugar levels
- How you can adjust your training to optimize your blood sugar levels
What is blood sugar or glucose?
First things first: the terms blood sugar and glucose level are synonyms. For the following reason:
When you eat food containing carbohydrates, your body breaks it down into a type of sugar called glucose. Glucose and fatty acids are the body's main sources of energy, and after a meal the fat is stored and the glucose is released into the blood - hence the terms blood sugar or blood glucose. The body recognizes that glucose has entered the bloodstream and triggers the endocrine system (the pancreas) to release insulin, which regulates glucose by causing cells to take it up for energy use and storage.
What can cause high or low blood sugar levels?
A low blood sugar level (hypoglycemia) can occur if you do not eat enough carbohydrates, drink alcohol, are ill or are taking certain medications.
High blood sugar levels (hyperglycemia) can occur if you eat a lot of carbohydrate-rich foods, due to lack of sleep, due to insulin insensitivity, but also due to stress, trauma or a chronic illness. It can also affect how your body responds to exercise. Studies show that people with high blood sugar levels can't take full advantage of the health benefits of exercise.
To lead a healthy life, it is important to recognize the signs of high or low blood sugar levels.
Both blood sugar levels that are too low and too high are difficult to detect and can easily go unnoticed, so the symptoms often go untreated. With a continuous glucose monitoring (CGM) device, you can see in real time how your diet, sleep, exercise, and stress levels are affecting your blood sugar. Monitoring and controlling your blood sugar levels is a great way to stay healthy and avoid metabolic disorders .
Why exercise is good for regulating blood sugar levels
When it comes to your health, exercise is one of the best things you can do. So it should come as no surprise that exercise is effective in keeping blood sugar levels steady. The muscles in your body need glucose for fuel, and when you exercise, the need for glucose increases because our muscles are activated. Exercise also increases the body's insulin sensitivity, which allows insulin to work more effectively and reduces blood sugar spikes faster.
How does sport affect blood sugar?
It's important to know that different types of exercise affect your blood sugar levels differently. How blood glucose levels change during exercise can depend on the following factors:
- The blood sugar level before exercise
- The type of training (aerobic or anaerobic)
- The length of the workout
Intense exercise (anaerobic) is likely to spike your blood sugar levels as it can release the hormone adrenaline, which stimulates the liver to release glucose faster.
In contrast, exercise at a steady pace and moderate intensity (aerobic exercise - short duration) uses fat as the main source of energy, which means that blood glucose levels remain stable.
Knowing how your body reacts to your workouts can help you avoid blood sugar spikes or lows . For example, if you notice a sharp increase during a workout, you can pay attention to what you eat before or during your workout and how much fluid you consume. More on that below! Now let's explore the question of which exercises lower or raise your blood sugar levels.
What are anaerobic exercises and how do they affect my blood sugar levels?
Anaerobic activities, such as interval training, are more intense and shorter and get you out of breath quickly. When you exercise anaerobically, your body primarily uses glucose, which means it draws on the glucose (glycogen) stored in your muscles and liver, which is why your blood sugar levels spike during these exercises to meet your body's needs. This also means that the spikes that occur during high-intensity exercise are nothing to worry about. The body responds as it should. That's what you want your body to do.
Examples of anaerobic exercise include: interval training, sprinting, weightlifting, strength training, spinning classes, high-intensity interval training (HIIT), Pilates.
What is aerobic exercise and how does it affect blood sugar?
Aerobic exercise is an activity that raises your heart rate at a steady pace and medium to low intensity. These are exercises where you can generally talk to other people. Unless you're swimming ;) Aerobic exercise does not require the body to draw on glucose stores (glycogen) in the liver, meaning the body does not need to generate an instant energy kick, but instead draws on energy from fats. This means that your blood sugar level generally remains the same or even drops slightly.
Examples of aerobic exercises are: Swimming, cycling, jogging, walking, rowing, zone 2 cardio, ashtanga, vinyasa, power and hot yoga
Exercising on an empty stomach: is fasting training good for my blood sugar?
Exercising on an empty stomach means exercising on an empty stomach. You can do this by fasting overnight and exercising first thing in the morning or before your first meal. The idea is that by the time you exercise, your body will run out of glucose stores and will be able to access the stored fat more easily than when you're fasting. However, this practice can cause blood sugar levels to drop during exercise. This drop is the sign that your body is low on energy (making it harder to recover). As a result, you put a lot of stress on your body, lose fitness instead of gaining it, and increase the risk of injury as well as your stress levels.
How the menstrual cycle affects your training and blood sugar levels
Most women are aware that their bodies go through different phases during the menstrual cycle . However, many people are not aware of how much these fluctuations affect their bodies. Sleep, sexual function, and metabolism are all linked to the endocrine system. In addition to our blood sugar levels, the endocrine system also controls the menstrual cycle. This explains why the hormonal phases can affect glucose metabolism during exercise. In other words, a workout that seemed easy in one phase and where blood sugar levels flattened out may seem more difficult in another phase and lead to higher blood sugar levels.
The hormones released during the different phases of menstruation appear to influence the dependence on glucose as an energy source as well as the glucose response to food and stress. Hello Inside has developed the Hello Hormones program to show how your blood glucose levels change during your cycle. This allows you to optimize your training and glucose response.
Our tips:
We have put together some tips on how you can optimize your blood sugar levels based on your training and vice versa.
You can maximize the positive effects of exercise on your blood sugar levels by incorporating the following tips into your training program:
General measures:
- Choose a sport that suits your menstrual cycle to feel your best.
- Pay attention to the drop in blood sugar and recharge your batteries (preferably a mixture of protein and carbohydrates, e.g. a yogurt with berries).
- If the workout lasts longer than 90 minutes, prepare a small snack that you can eat during the workout (e.g. a banana or 1-2 energy chewing gums).
- Incorporate a fasted workout by doing 15-20 minutes of HIIT or aerobic exercise in the morning.
- If you exercise in the evening, opt for a gentle workout so you can sleep better and recover. (Bonus: A good night's sleep has a positive effect on blood sugar levels the next day).
This will prevent your blood sugar level from getting too low:
- Move your body by going for a 15-minute walk, taking the stairs or getting up from your desk every 20 minutes to stretch.
- Avoid hot baths, saunas and steam baths after training
- Exercise no later than 2 hours before going to bed
To avoid blood sugar peaks (or spikes):
- Do light or moderate exercise before your first meal
- Try to go for a walk after meals: Studies show that exercise within 30 minutes of a meal significantly lowers blood sugar levels.
Key Takeaways
Glucose serves as fuel for your muscles during exercise. If you do aerobic exercise such as walking or swimming, your blood glucose levels will remain stable or possibly drop. If you do anaerobic (intense) exercise such as weightlifting, your blood glucose levels will rise quickly and may even spike.
Fasting exercises and adapting your training to your menstrual cycle can both boost your glucose metabolism.
It is advisable to measure your blood glucose before and after training. Using a CGM makes this easier and allows you to measure your blood glucose levels during exercise. Based on the results, you can determine how high your blood glucose level should be during exercise and how you should react to it. For example, you can optimize your energy level before an anaerobic exercise, or if you are training on an empty stomach and notice that your blood glucose level is dropping, you can have a prepared snack.
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