Do You Burn More Fat Running On An Empty Stomach

Running on an empty stomach has been a topic of considerable debate in the fitness community. Some argue that exercising in a fasted state can help burn more fat, while others believe it can be detrimental to performance and overall health. As an avid runner who has experimented with running on an empty stomach, I’ll delve into the scientific evidence and share my personal experiences to shed light on this hotly contested subject.

The Theory Behind Running on an Empty Stomach

Proponents of running on an empty stomach claim that when you exercise without having eaten recently, your body will tap into its fat stores as the primary fuel source. The logic is that since your glycogen (carbohydrate) stores are depleted after an overnight fast, your body will turn to burning fat instead. This, in theory, leads to increased fat loss and improved body composition.

Several studies have suggested that running on an empty stomach may indeed enhance fat burning. One study published in the Journal of Applied Physiology found that participants who performed aerobic exercise in a fasted state showed significantly higher fat oxidation rates compared to those who had consumed a meal beforehand. Another study published in the Medicine and Science in Sports and Exercise journal reported similar findings, suggesting that fasted exercise can lead to increased fat utilization.

Performance and Fuel Availability

While the potential fat-burning benefits of running on an empty stomach are intriguing, it’s essential to consider the impact on performance. Running is a demanding physical activity, and our bodies rely heavily on carbohydrates for fuel during high-intensity exercise. When you run on an empty stomach, your glycogen stores are already low, which can result in decreased energy levels and a compromised ability to maintain intensity and endurance.

From my personal experience, I’ve found that running on an empty stomach can lead to a noticeable drop in performance. I feel more fatigued and struggle to maintain my usual pace and distance. However, it’s important to note that individual responses may vary, and some individuals may adapt better to fasted exercise than others.

Considerations for Long-Term Sustainability

While running on an empty stomach may have its unique benefits for fat burning, it might not be suitable or sustainable for everyone in the long run. It’s important to listen to your body and prioritize overall health and well-being.

Remember that food provides us with essential nutrients, including carbohydrates, proteins, and fats, that are crucial for optimal performance, recovery, and overall health. Running on an empty stomach may not provide sufficient fuel for your body to function optimally, especially during intense or prolonged workouts.


So, does running on an empty stomach burn more fat? The scientific evidence suggests that it may indeed enhance fat burning. However, it’s crucial to consider the impact on performance and overall well-being. If you choose to experiment with running on an empty stomach, pay attention to how your body responds and adjust accordingly.

Ultimately, there is no one-size-fits-all approach when it comes to nutrition and exercise. It’s essential to find a balance that works for you, fueling your body adequately for optimal performance while considering your goals and preferences. As always, consulting with a healthcare professional or registered dietitian can provide personalized guidance based on your specific needs and circumstances.