Fasted cardio – Is a workout on empty stomach effective?

A woman is tying her shoes before her morning run

It’s believed that fasted cardio is an effective way to boost fat burning. That doing a workout on an empty stomach, instead of having eaten before, provides the optimal conditions for weight loss. But is that true?

Let’s have a look at fasted cardio and whether it’s more effective for fat loss.

What is fasted cardio?

Fasted cardio is, as the name might suggest, cardio done on an empty stomach. It’s done before eating the first meal of the day, usually in the morning before breakfast. Often with the goal of weight loss.

It’s believed that doing cardio on an empty stomach will enhance fat loss. That instead of using the food in the stomach, the body will use fat as fuel.

But is it a way to burn fat quicker? Let’s find out.

Related:3 effective HIIT workouts on a treadmill

Is fasted cardio better for fat loss?

A study in 2016 decided to find out if fasted cardio was better for fat loss. They used a group of 20 fit women. They were put in a calorie deficit and ate the same amount of calories compared to their BMR. Every morning the women had a 1-hour cardio session done on a treadmill. They made sure that all participants would burn the same amount of calories in the workout.

There was only one thing that wasn’t the same amongst all 20 of the women. Half of the group had a shake before the workout the other half didn’t.

After 4-weeks of doing this, they had their expected result. Both groups had lost almost 1 kg (2lbs). As a result of this study, we can conclude that cardio done on an empty stomach isn’t more effective for fat loss.

Related: How to set your macros for fat loss


It’s believed that fasted cardio is far more effective for fat loss than fed cardio. However, a study from 2016 could conclude that to be wrong.

Whether you eat or not before cardio doesn’t matter. The thing that matters is getting the cardio done and being in a calorie deficit.