Fasted training – is it a good idea?
Training on an empty stomach is a controversial topic in the world of sports and fitness. Supporters argue that exercising before breakfast may enhance fat-burning, while critics of intense workouts without food highlight the potential strain on the body and the increased risk of losing previously gained muscle mass. So, is it possible to exercise on an empty stomach? Is morning training without food a good idea? How should fasting workouts be planned?
Table of contents
- What is fasting training?
- Is it worth exercisin on an empty stomach? Pros and cons
- Fasting training and type of activity
- Exercising on an empty stomach - who is it for?
- Morning training on an empty stomach - how to plan it?
- How long after eating can you exercise?
- What are the alternatives to fasting training?
- Supplements supporting fasting trainings
- Fasting training - summary and tips
What is fasting training?
Fasting training refers to physical activity performed before the first meal of the day - on an empty stomach. It’s most commonly done in the morning, after at least eight hours of overnight fasting. This training method has grown in popularity alongside the rise of intermittent fasting (IF).
Fasting workouts, which aim to utilize the body’s fat reserves as the primary energy source, can include a variety of activities. Strength training on an empty stomach is commonly practiced, but aerobic workouts or cardio before breakfast are also gaining traction.
Is it worth exercising on an empty stomach? Pros and cons
Working out in a fasted state has its benefits, but it also carries certain risks. Before incorporating fasted training into your routine, it's important to understand how this type of activity may affect your body by considering both its potential advantages and disadvantages. Additionally, when choosing to exercise while fasting, it’s crucial to pay attention to your individual response, as everyone may experience different effects.
Benefits of exercising on an empty stomach
Current research suggests that engaging in intense physical activity on an empty stomach may support fat loss by increasing lipid and fatty acid oxidation and encouraging the body to use fat as its primary energy source.
Additionally, some studies indicate that training after a fasting period can improve metabolic function by enhancing tissue sensitivity to insulin. This, in turn, may boost the efficiency of glucose utilization during workouts.
For some individuals, fasted exercise may also help regulate appetite throughout the day. However, this effect is highly individual - while some people experience reduced hunger, others may find that exercising on an empty stomach actually increases their appetite.
Disadvantages of training on an empty stomach
Although physical activity on an empty stomach has certain benefits, it also has its disadvantages. Scientific research indicates that intense exercise before breakfast can contribute to a significant increase in cortisol levels in the body, which can negatively affect the functioning of the human body, including promoting metabolic disorders, intensifying catabolic processes, and the development of diabetes.
As if that were not enough, people who train on an empty stomach may experience a decrease in physical performance due to weakness and lack of energy to perform intense exercise, which can adversely affect the quality and effectiveness of training. Athletes who exercise on an empty stomach may also have difficulty focusing and concentrating, which can be particularly undesirable among athletes who practice activities that require precision and accuracy.
There is also evidence suggesting that exercising on an empty stomach may lead to an increase in insulin levels, which can inhibit lipolysis - the process of breaking down fat. Since the body may use not only fat but also amino acids as an energy source during intense physical activity, there is a risk of increased muscle catabolism, meaning the breakdown of muscle tissue.
Moreover, data indicates that working out immediately after waking up may negatively impact spinal health by increasing the risk of intervertebral disc herniation.
Fasting training and type of activity
When considering exercising on an empty stomach, it's important to align your training with your goals and the type of exercise you choose. Is aerobic training, cardio, or gym workouts effective when done fasting?
Aerobic training while fasting - effectiveness
Aerobic training, also called oxygen exercise, involves low-intensity activity performed at about 65% of your maximum heart rate and typically lasts between 30 and 60 minutes. Compared to strength training, it is less demanding and can be effectively done on an empty stomach. This approach can promote fat loss and support weight management, partly because glycogen stores are significantly depleted after an overnight fast. Therefore, aerobic exercise while fasting can be a helpful strategy for those aiming to improve their body composition and shed excess weight.
Cardio on an empty stomach - is it worth it?
Cardio training involves maintaining a slightly higher heart rate than during aerobic exercise, typically around 70-80% of your maximum heart rate. These medium-intensity workouts usually last less than 20 minutes and include activities like fast cycling or intense jogging.
Some studies suggest that doing cardio on an empty stomach, similar to aerobic exercise, can be beneficial for certain individuals, especially those who are overweight and aiming to burn fat. There is also evidence indicating that performing cardio before breakfast may improve aerobic capacity more than training after a meal, while also encouraging an increase in glycogen stores in the body.
However, it’s important to remember that physical activity before a meal should not be too long or intense. For more demanding workouts, it’s better to exercise after a balanced breakfast, which provides the body with enough energy and helps protect the muscles from catabolism.
Strength training on an empty stomach - does it make sense?
Strength training on an empty stomach is a high-intensity form of exercise that, unlike aerobic workouts, can pose greater risks to the body and may lead to unwanted effects.
Not replenishing glycogen stores before intense training can result in decreased strength and reduced endurance during the workout, which negatively affects training effectiveness, increases fatigue, and slows down metabolism. Moreover, failing to provide the body with enough protein before exercise can accelerate catabolic processes, causing muscle mass loss.
For these reasons, strength training on an empty stomach is not recommended for those aiming to build muscle and improve their physique, as it is more likely to cause harm than benefit, potentially leading to the opposite of the desired outcome.
Exercising on an empty stomach - who is it for?
When considering physical activity on an empty stomach, the first step is to clarify your training goals. If your main focus is building muscle mass or improving endurance, you will likely find that exercising on an empty stomach works against these goals and doesn’t help achieve the desired results.
However, if your aim is to reduce body fat or boost fatty acid oxidation, training on an empty stomach might be a good option.
It’s important to remember that exercising on an empty stomach isn’t ideal for everyone. The body’s tolerance for intense exercise without prior food intake varies from person to person, so it’s crucial to pay attention to how your body responds when deciding the best time to work out.
Morning training on an empty stomach - how to plan it?
It’s best to start training on an empty stomach with a gentle warm-up and breathing exercises. Activities like swimming, walking, light jogging, or Pilates can also be good choices.
To make the most of exercising on an empty stomach, you should prepare your body properly for morning workouts without food and follow these recommendations:
- Fasting training should be low to moderate intensity, and the duration should not exceed 60 minutes.
- The night before fasting exercise, it’s a good idea to have dinner rich in complete protein and complex carbohydrates.
- Before and during training on an empty stomach, remember to drink enough fluids and stay well hydrated.
- Consider taking dietary supplements containing BCAA amino acids before training to help reduce the risk of muscle breakdown by inhibiting catabolic processes.
- After finishing your workout, eat a nutritious post-exercise meal to support recovery and repair the microdamage caused during training.
How long after eating can you exercise?
If you want to train on an empty stomach, you should allow at least an 8-hour gap between meals, which is why exercising on an empty stomach is usually done after overnight fasting.
If you choose to exercise during the day and skip training on an empty stomach, it’s important to eat a balanced pre-workout meal about 1.5 to 2.5 hours before your activity. However, the type and composition of the meal are key. Foods that take longer to digest will require a longer wait before exercising. On the other hand, if you have a light snack like yogurt, muesli, or a banana, you can usually work out about 30 to 90 minutes after eating.
What to eat after training on an empty stomach?
After exercising on an empty stomach, it’s important to eat a nutritious meal that supplies your body with both protein and carbohydrates. Good options include:
- Oatmeal with milk, banana, and peanut butter
- Egg omelet with vegetables
- Vegetable salad with rice, groats, or pasta, served with natural yogurt
- Sandwich with cottage cheese or a dry legume spread and vegetables.
What are the alternatives to fasting training?
A good alternative to training on an empty stomach is to exercise after a small snack. Before your workout, it’s helpful to eat a meal rich in carbohydrates and also include enough protein. Some good pre-workout meal ideas are:
- OstroVit THE BAR (60 g vanilla-flavored bar), a valuable source of protein that also provides carbohydrates
- OstroVit Oat My Day (200 g, apple and cinnamon flavor), known for its simple ingredients and delicious taste, delivering important micronutrients
- OstroVit High Protein Pancakes (400 g, strawberry and raspberry flavor), which are sugar-free, easy to prepare, and offer a concentrated dose of beneficial nutrients.
Supplements supporting fasting trainings
To enhance the effectiveness of physical activity on an empty stomach, it’s worth using high-quality dietary supplements that provide beneficial compounds and support achieving your training goals. Consider supplements containing:
- Branched-chain amino acids (BCAAs), such as OstroVit BCAA 8-1-1 (400 g, orange flavor), which can help protect muscles from breakdown during exercise, improve endurance, and reduce fatigue.
- L-carnitine, for example OstroVit L-Carnitine (210 g, natural flavor), which supports the transport of fatty acids to the mitochondria, aiding fat burning during fasted workouts.
- Electrolytes, like OstroVit Electrolytes (20 effervescent tablets, orange flavor), which help maintain water and electrolyte balance, ensuring proper nutrient supply and hydration, reducing the risk of muscle cramps and dehydration.
- Caffeine, such as OstroVit Caffeine powder (200 g, natural flavor), a natural stimulant that can boost energy, improve concentration, and enhance endurance and performance.
Fasting training - summary and tips
Fasting training can support fat burning, but it’s important to remember that overall weight loss depends not just on when you exercise, but primarily on maintaining an energy deficit throughout the day. While exercising on an empty stomach may improve metabolic adaptation, it’s not the right choice for everyone.
Training before breakfast can help reduce excess weight and is suitable for activities like aerobic exercise. However, exercising on an empty stomach can also cause muscle loss, which may lead to decreased strength and performance. For this reason, fasted training is not recommended for athletes focused on building muscle mass or sculpting their physique.
The key to success lies in adjusting the timing and type of exercise to your fitness level and individual needs, while maintaining a balanced diet and considering useful dietary supplements. Exercising on an empty stomach can offer benefits, but it should be carefully planned and tailored to your personal preferences.
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