Many people wonder if they should exercise on an empty stomach or not. Some believe that it can help them burn more fat and lose weight faster, while others think that it can harm their health and performance. So, what is the truth?
Is working out on an empty stomach good or bad? What are the pros and cons of exercising on an empty stomach? In this blog, we will try to answer these questions and provide some tips on how to exercise on an empty stomach safely and effectively.
Table of Contents
What Does It Mean to Exercise on an Empty Stomach?
Exercising on an empty stomach means that you do not eat anything for at least three to four hours before your workout. This is also known as “fasted exercise” or “training in a fasted state.”
When you exercise on an empty stomach, your body relies on its stored energy sources, such as glycogen (carbohydrates) and fat, to fuel your muscles and organs.
However, the amount and type of energy that your body uses depends on several factors, such as the intensity and duration of your exercise, your fitness level, your diet, and your hormones.
Empty Stomach Workout & Studies:
Some researchers found that working out in the morning before eating anything helps burn more fat, lowers bad cholesterol, boosts good hormones, and makes you eat less during the day.
But these studies are not very reliable, because they only looked at young fit men for a short time, and they may not apply to other people. Also, most experts still say that eating some carbs before exercising is better for your performance.
Another study in the NSCA Journal says that it doesn’t matter if you eat or not before cardio. You burn the same calories. However the study’s author Brad Schoenfeld says that not eating and doing hard cardio can lower your protein by up to 10.4%.3 That’s bad if you want to gain muscle. And it can affect your performance too.
How to Exercise on an Empty Stomach Safely and Effectively
If you decide to exercise on an empty stomach, here are some tips to follow:
Choose the right type of exercise: As mentioned earlier, exercising on an empty stomach may be more suitable for low to moderate intensity aerobic exercise, such as walking, jogging, cycling, or swimming. These types of exercise can help you burn fat without compromising your performance or muscle mass.
However, if you want to do high intensity or long duration workouts, such as sprinting, HIIT, weightlifting, or marathon running, you may want to eat something before your workout to provide your body with enough energy and prevent muscle breakdown.
Choose the right time of the day: The best time to exercise on an empty stomach is in the morning, after a good night’s sleep. This is because your glycogen levels are naturally lower in the morning, and your body is more likely to use fat as fuel.
However, if you are not a morning person, or if you have a medical condition that requires you to eat regularly, you may want to exercise at a different time of the day. In that case, you should wait at least three to four hours after your last meal before you exercise.
Drink plenty of water: Water is essential for your hydration, digestion, circulation, and temperature regulation. When you exercise on an empty stomach, you may lose more water through sweating and breathing.
Therefore, you should drink plenty of water before, during, and after your workout to prevent dehydration, which can impair your performance and health. You can also add some electrolytes, such as sodium, potassium, and magnesium, to your water to replenish the minerals that you lose through sweating.
Eat a balanced meal after your workout: After you exercise on an empty stomach, your body needs to replenish its energy and nutrients. Therefore, you should eat a balanced meal within one to two hours after your workout.
Your meal should include a combination of carbohydrates, protein, and healthy fats. Carbohydrates will help you restore your glycogen levels, protein will help you repair your muscle tissue, and healthy fats will help you regulate your hormones and inflammation.
Some examples of post-workout meals are oatmeal with eggs and nuts, chicken and rice with vegetables, or yogurt with fruit and granola.
Working Out on an Empty Stomach Pros and Cons
There are some potential benefits and drawbacks of exercising on an empty stomach. Here are some of them:
Pros
- It may enhance fat burning. Some studies have suggested that exercising on an empty stomach can increase the rate of fat oxidation (burning) during low to moderate intensity aerobic exercise, such as walking, jogging, cycling, or swimming.
- It may improve insulin sensitivity. Insulin is a hormone that regulates your blood sugar levels and helps your cells absorb glucose (sugar) from the bloodstream. Insulin sensitivity refers to how well your cells respond to insulin.
- It may boost your growth hormone levels. Growth hormone (GH) is a hormone that stimulates your muscle growth, bone density, and metabolism. GH levels are naturally higher during the night and early morning, and they decline throughout the day.
Cons
- It may impair your performance. Exercising on an empty stomach may not be the best option for high intensity or long duration workouts, such as sprinting, HIIT, weightlifting, or marathon running. This is because these types of exercise require a lot of energy and rely heavily on glycogen as fuel.
- It may increase your muscle breakdown. When you exercise on an empty stomach, your body may not only use fat and glycogen as fuel, but also protein. Protein is the building block of your muscles, and when your body breaks down protein, it can damage your muscle tissue and reduce your muscle mass.
- It may affect your appetite and mood. Exercising on an empty stomach may make you feel hungrier and more irritable after your workout. This is because your blood sugar levels may drop and your hunger hormones, such as ghrelin and leptin, may fluctuate.
The Final Verdict
Exercising on an empty stomach is a controversial topic that has both pros and cons. It may help you burn more fat, improve your insulin sensitivity, and boost your growth hormone levels.
However, it may also impair your performance, increase your muscle breakdown, and affect your appetite and mood. Therefore, you should weigh the benefits and risks of exercising on an empty stomach, and consult your doctor before trying it.
If you decide to exercise on an empty stomach, you should choose the right type of exercise, time of the day, hydration, and post-workout meal to optimize your results and health.
Frequently Asked Questions (FAQs)
Here are some frequently asked questions about exercising on an empty stomach:
Yes, you can exercise with an empty stomach in the morning, as long as you choose the right type of exercise, drink plenty of water, and eat a balanced meal after your workout. Exercising on an empty stomach in the morning may help you burn more fat, improve your insulin sensitivity, and boost your growth hormone levels.
It depends on the type, intensity, and duration of your workout, and your diet. If you do low to moderate intensity aerobic exercise, such as walking, jogging, cycling, or swimming, you may not lose much muscle if you workout on an empty stomach.
However, if you do high intensity or long duration workouts, such as sprinting, HIIT, weightlifting, or marathon running, you may lose some muscle if you workout on an empty stomach. To prevent muscle loss, you should eat something before your workout, or consume enough protein in your diet.
There is no definitive answer to this question, as it depends on your goals, preferences, and health. Exercising on an empty stomach may have some benefits, such as enhancing fat burning, improving insulin sensitivity, and boosting growth hormone levels.
However, it may also have some drawbacks, such as impairing your performance, increasing your muscle breakdown, and affecting your appetite and mood. Therefore, you should weigh the pros and cons of exercising on an empty stomach, and consult your doctor before trying it.
When you exercise on an empty stomach, your body uses its stored energy sources, such as glycogen and fat, to fuel your muscles and organs.
However, the amount and type of energy that your body uses depends on several factors, such as the intensity and duration of your exercise, your fitness level, your diet, and your hormones.
Exercising on an empty stomach may have some positive or negative effects on your health and performance, depending on these factors.
References
Is exercise best served on an empty stomach?1
Does Cardio After an Overnight Fast Maximize Fat Loss?2
Body composition changes associated with fasted versus non-fasted aerobic exercise.3
Amelia Johnson, as a dedicated fitness enthusiast, believes that a strong body and a sound mind go hand in hand.
Her journey began when she discovered the transformative power of exercise and clean eating. Her love for fitness extends beyond mere physical activity—it’s a lifestyle. She pours her heart into writing about holistic health, nutrition, and wellness. Her articles are a blend of science-backed advice, personal anecdotes, and practical tips.
