Besides promoting weight loss, the ketogenic diet is often used to boost overall health. The diet is well known for its ability to regulate blood glucose levels and ketone levels but working out while on the keto diet can take your health to the next level.
Let’s explore how a workout affects blood glucose and ketone levels.
Blood Glucose and Keto
It’s impossible to talk about glucose without talking about carbs, and there’s a good reason why: carbs are metabolized in the body as glucose. That means every time you eat carbs (whether it’s white pasta or a carb-laden root veggie), your body converts carbs into blood sugar (glucose), which is then either used as energy or stored for later.
Because the ketogenic diet is low carb, you’re not ingesting as many carbs, which means your body is using or storing as much glucose. This also means that your blood sugar levels don’t fluctuate up and down as much. Studies show that the keto diet is so effective in lowering blood sugar that it’s being used to help diabetics lower their HbA1c levels. After a 4-month keto diet trial, the study participants had 16% lower blood sugar levels.  In addition to lower HbA1c levels, the keto diet can also improve insulin sensitivity. Another study demonstrated that the keto diet could improve fasting blood glucose levels and improve insulin sensitivity by up to 75%. 
Ketone Levels and Keto
The keto diet doesn’t just improve blood glucose levels – it also affects ketone levels. When carbs are restricted, the body needs another form of energy, and it begins to use fat as fuel – this is why fats are so important when you’re on keto. Free fatty acids are broken down in the muscle for immediate energy, but some free fatty acids are also broken down in the liver. When they are broken down in the liver, ketone bodies are produced.
How Exercise Affects Glucose and Ketone Levels
The keto diet is excellent for improving glucose levels and producing ketones, but it’s not your only option. Add exercise to the mix, and you’ll see an improvement in blood glucose regulation. When you exercise, GLUT 4 transporters are activated in the cells of your muscles. When these GLUT 4 transporters are activated, they escort glucose out of your blood – and into your muscles for energy. Less glucose in your blood means lowered blood glucose levels.
Whether you love a long run on the bike path or a quick HIIT session, exercise affects blood sugar levels.
The American Heart Association recommends about 150 minutes of moderate exercise each week for optimal heart health. That’s because exercise – including both endurance training and resistance training – can help regulate your blood glucose levels. According to a study published in the Journal of Physiology, exercise can affect blood glucose in a few ways, including:
- Promoting energy through fat oxidation
- Improving glucose tolerance
- Improving insulin sensitivity
Researchers specifically noted that these effects of exercise on blood sugar were the most noticeable when exercising in a fasted state. 
Ketone Levels During and After Exercise
There’s no denying that exercise – any and all exercise – improves your blood glucose regulation, but the benefits don’t stop there. Exercise also increases ketone levels. When you’re exercising, your body typically relies on glycogen (stored glucose) for energy. As you continue to exercise, the body uses more and more glycogen. If your glycogen stores are depleted, your body needs energy, so it will use ketone bodies (produced from fat).
Studies show that athletes who use up a lot of glycogen (such as marathon runners) typically have higher ketone levels after working out.  However, athletes who carb load may not see these results because they had ample stores of glycogen. Athletes who had restricted carbs were more likely to remain in ketosis thanks to plentiful ketone levels.
Keeping Exercise in Your Daily Routine
From HIIT to weightlifting to swimming to trail running, there are endless reasons to add more exercise to your weekly routine. Exercise improves heart health, blood sugar levels, ketone levels, and your mood.
What is your favorite way to add more exercise to your week?
- Yancy, William S, et al. “A Low-Carbohydrate, Ketogenic Diet to Treat Type 2 Diabetes.” Nutrition & Metabolism, BioMed Central, 1 Dec. 2005.
- Boden, Guenther, et al. “Effect of a Low-Carbohydrate Diet on Appetite, Blood Glucose Levels, and Insulin Resistance in Obese Patients with Type 2 Diabetes.” Annals of Internal Medicine, American College of Physicians, 15 Mar. 2005.
- Van Proeyen, Karen, et al. “Training in the Fasted State Improves Glucose Tolerance during Fat-Rich Diet.” The Journal of Physiology, Blackwell Science Inc, 1 Nov. 2010.
- Doutorado, and Educação Física da Universidade Católica de Brasília. “Methods to Identify the Lactate and Glucose Thresholds… : The Journal of Strength & Conditioning Research.” LWW.
- Søgaard, D, et al. “High-Intensity Interval Training Improves Insulin Sensitivity in Older Individuals.” Acta Physiologica (Oxford, England), U.S. National Library of Medicine, Apr. 2018.
- Koeslag, J H, et al. “Post-Exercise Ketosis.” The Journal of Physiology, U.S. National Library of Medicine, Apr. 1980.
Kathryn Trudeau is a content writer and educational professional whose work centers on health and wellness and organic living. She has a passion for nutrition and fitness. She loves matcha, running, and crocheting.