Fact Check: Does Fasted Cardio Result in Greater Weight Loss than Normal Cardio?

Does fasted cardio actually work? (Image via Pexels/Photo by William Choquette)
Does fasted cardio actually work? (Image via Pexels/Photo by William Choquette)

Fasted cardio is a widely popular concept since the concept was first introduced in 1999 by Bill Phillips. As per the concept, working out in an empty stomach can maximise fat burning.

The theory claims that the body burns fat to generate energy during fasted cardio. Insulin, glycogen and blood sugar levels drop overnight, and the body’s primary source of energy is glycogen. While working out in a fasted state, the body needs to generate energy. When it doesn’t find glycogen to burn for energy, it burns the stored fat to generate the required energy.

Does fasted cardio work better than normal cardio?

There’s no clear-cut answer to that. It can be both a yes and a no.

Here’s what happens

When you work out in a fasted state, the body burns more fat. This is a technique that bodybuilders use before they walk out on stage to lean out as much as possible. In fact, approximately 20% more fat can be burned when working out in a fasted state.


However, even when you indulge in rigorous weight training, if done in a fasted state, it doesn’t burn fat over a 24-hour period. In fact, having carbs before working out could possibly burn more calories than a fasted workout.

More often than not, athletes use the ‘fasted cardio’ method to enable their bodies to adapt to low blood sugar levels. Even though it helps athletes burn fat for fuel, it doesn’t necessarily result in fat loss or improvement in their lean physique.

What happens when you workout in an empty stomach?

There have been ample experiments that have shown how the body reacts to working out in a fasted state.

When you wake up, your body remains in a catabolic state, which is aligned with stress. At this point, the body looks to break down anything for energy, and it turns to burning fat due to lack of carbohydrates.


Unfortunately, if you continue that for a long time, the body will not have the energy to train at its full capacity. That would lead to muscle loss and decline in overall health. In fact, it’s believed that hitting too heavy in an empty stomach can lead to muscle depletion.

How do you know fasted cardio is not for you?

It’s a given that not all types of cardio are for everyone. Some may prefer HIIT sessions while others prefer LISS.

You can try fasted cardio and see how your body reacts to it. If your body reacts positively, you can continue it. However, if you constantly feel nauseous and dizzy, it’s a given that this is not for you.

In such cases, what you need to do is probably consume significantly low calories before your cardio sessions. That will be a dietary change and boost your metabolism for the rest of the day as well.


Bottom line

There’s no reason to believe that fasted cardio does not work. However, it would be incorrect to assume that it works better than normal cardio.

Everyone has a different body type and a different comfort level. Eventually, you can only lose weight when you’re in a calorie deficit, regardless of the type of diet you’re following.

At the end of the day, you need to find the balance between carbohydrates, fats and proteins, which will help you reach your goal such as fat loss or muscle gain.

Fasted cardio isn’t a magic formula that will help you lose weight even if you’re not in a calorie deficit or not following a proper diet and workout routine.

Edited by Bhargav