Working out on an empty stomach, also known as fasted cardio or working out in a fasted state, refers to exercising before eating breakfast or fueling oneself with any type of food.
It is another relatively recent health and fitness trend that many people have strong opinions about.
Some swear by an empty stomach workout for its alleged fat-burning benefits, while others warn against its potential disadvantages of disrupting muscle building.
A few studies that support either side, which adds to the intensity of opinions around this subject.
You may stand anywhere in this heated argument, or you may have formed an opinion yet.
But it remains an important discussion about what really matters for your body and benefits it, and how to avoid harming it.
Where Did The Trend Start?
It all started when Alborg and Felig conducted a study in 1976 that suggests that carbohydrates consumption during an intense activity leads to carbohydrates, not fat, being used as fuel.
In another study in 1997, Horowitz and colleagues found that fat oxidation was reduced during exercise when carbohydrates were ingested before working out.
Both studies helped kickstart a general belief in the health and fitness community that working out on an empty stomach results in higher fat burn.
A wave of skepticism also surrounded that notion about whether it is even true and how harmful it can be to follow it.
Do You Burn More Fat Exercising On An Empty Stomach?
We would not phrase it that way.
However, when you work out on an empty stomach, you don’t have excess calories from a recent meal, which encourages your body to rely on stored fat or Glycogen as fuel instead.
A study conducted in 2015 and 2016 shows that exercise in a fasted state lowers body fat percentage.
Another study conducted in 2016 concludes that empty stomach exercise reduces 24-hour energy intake in active male adults.
That said, most studies that support the fact that fasted exercise aids weight loss were short-term, meaning they don’t monitor subjects for a long time or offer long-term evidence.
Besides, a 2014 study on 20 healthy young women proves that those who worked out empty stomach burned as much fat as those who ate before exercising.
Could Fasted Exercise Be Harmful?
Exercising in a fasted state can be less ideal than its fans think. For starters, many people experience sudden energy depletion or fatigue mid-workout if they don’t eat beforehand.
Also, exercising without pre-fueling makes you hungrier and more prone to overeating than if you exercise when you’re well-fed, which counteracts the general goal of losing weight and burning fat.
Also, mid-to-high intensity workouts on an empty stomach can lead to blood glucose and stored fat being wholly depleted.
Your body may resort to releasing cortisol and breaking down muscle tissue to use protein as fuel instead. Less protein means less ability to build and repair muscle.
Losing muscle is not something you want either; muscles give you shape, definition, and strength. Burning body fat should not be at the cost of your own muscle mass.
This general state of fatigue and muscle loss means that you won’t be able to improve your performance or increase its intensity over time.
That implies a limited exercise capacity, so your exercise will be far less efficient.
On the other hand, someone who eats well before working out is just fueled to push harder and improve over time.
So, working out on an empty stomach is not always as fruitful as it may seem.
So, Should You Eat Before Your Exercise Or Not?
Deciding whether to work out in a fasted state and risk loss of energy or eat beforehand and not burn enough fat can be confusing.
This article is not about telling you that you have to do fasted cardio or that you should not; we just want you to do what is best for you. The best is unclear so far because research is still relatively limited.
Therefore, feel free to try out fasted cardio, maybe a low-intensity exercise or some morning yoga so that you don’t put too much stress on your body.
Furthermore, listen to your body, and it will tell you when it is too tired or if a particular practice is too much.
The most agreed-upon fact is that eating right and working out is generally best for the human body because this is how you build and protect muscle while you burn fat.
You may ask what eating right for exercise means, especially in the morning, and that we shall answer.
What Should You Eat On An Empty Stomach Before Working Out?
Before we recommend you pre-workout food, we must remind you that you should not exercise on a full stomach, which can lead to nausea, reflux, hiccups, and vomiting. Ouch!
What you need to do is eat the right food to provide the body with energy two to three hours before your workout, especially if it is a whole meal. But what is the right food?
You need the right balance between carbs, fats, and protein, with a sufficient amount of hydration.
We need carbohydrates because they are the primary fuel for energy for the most intense workouts, but where should we look for healthy carbs?
Healthy choices for carbohydrates include whole-grain bread, brown rice, energy bars, oats, apples, or bananas.
The latter is also packed with potassium that boosts metabolism, provides energy, stabilizes blood pressure, and prevents muscle cramps and fatigue.
You can also find potassium in sweet potatoes, strawberries, and legumes.
Healthy fats help the body absorb essential vitamins and minerals. Also, they help us store energy.
So, while it is desirable to burn fat, and it may seem like “fat” is always a bad word, having a little fat in your diet from the right sources is actually vital for a healthy lifestyle.
We recommend looking into sources of nutritious fats such as avocados, olive oil, fatty fish, peanut butter, soymilk, walnuts, olives, and trail mix.
We see you looking at that bar of milk chocolate, and it won’t work here.
We have always somehow known that we need protein, but why? Well, protein boosts your immune system and speeds up wound healing.
Furthermore, it is a necessary building block for bones, cartilage, skin, and blood, which builds, maintains, and repairs muscle fibers too.
Protein can be found in peanut butter, trail mix, protein powder, protein shakes, eggs, oats, cottage cheese, chicken, Greek yogurt, and sprouts.
Furthermore, pre-workout low-fat milk smoothies are an excellent way to get sufficient carbs and protein.
Finally, don’t forget to hydrate before the workout with two to three cups of water.
Other hydrating foods are caffeine-free teas, coconut water, fruit-infused water, bell peppers, zucchini, and spinach, which provide you with much-needed fibers for improved digestion as well.
There are endless health and fitness trends that try to find creative ways to lose weight, and exercising in a fasted state is no different.
While there are studies that swear by its abilities to burn fat, more long-term research is needed before we can tell you with our whole chest to work out before eating.
The most important thing to do is to listen to your body and how it reacts should you try this fasted cardio.
That said, eating a well-balanced, nutritious meal with carbs, fats, and protein two hours before a workout is a fail-safe system that provides the body with energy and protects it from harm.
Hydration is also vital.
Stay safe and healthy!
Andreea is a fitness enthusiast with a keen interest in nutrition. She has gone from 98Kg to 70Kg through relentless hard work and getting her nutrition right with the help of a personal trainer.
She writes articles to empower anyone to take control and not let go of their mental and physical health.