There is a lot of conflicting advice as to whether you should fast before training or if you should eat a small snack to help you get through your workout. That can make it extremely difficult to know who to listen to in order to get the best results possible. However, if you know a thing or two about the human body and how it works, then you would probably realize that fasting is the way to go. Why?

As Dr. Mercola explains on Peak Fitness, “When you exercise while fasting, it essentially forces your body to shed fat, as your body’s fat burning processes are controlled by your sympathetic nervous system (SNS), and your SNS is activated by exercise and lack of food.” In other words, when you combine exercise and an empty stomach, you start a chain reaction that results in the greatest fat burn possible.

Because of this, working out first thing in the morning, before breakfast, is a great option as your tummy is going to be completely empty. Another optimal time is right after you get out of work as your last meal should have been around five hours prior (that is, if your lunchtime is roughly in the middle of your shift).

Once your workout session is over, your body will be ready for some nourishment though, so be sure to give it a high quality protein source within 30 minutes post-exercise. This will help give your muscles the nourishment they need to repair themselves while also providing you some energy you’re likely to need at that point.

Of course, if you try fasting before exercising and it doesn’t feel right, then go ahead and have something little—preferably a protein versus a carb. Everyone is different, so if fasting doesn’t work for your body, that is okay too.