Can exercising on an empty stomach help me burn more fat?

Exercising on an empty stomach does not help you burn more fat.  Our energy sources are stored in a few different places, based on how easy it is to access.  Our fat stores are the last place we go to for extra energy.

In general it is not a good idea to exercise on an empty stomach.  Kind of like you wouldn't take a trip in your vehicle and not feul up first.  It is recommended to eat an easily digestable snack 1-2 hours beforehand.  This way, you won't be uncomfortable from eating, but at the same time you will have energy/fuel for your activity.  Eating right after an activity is a good idea.  Don't overeat, but end with a protein shake and replenish your carbs so you have the energy to go again tomorrow at a strong level.

Fat burning comes from the types and amount of exercise you do.  Generally if you find exercises that use your quick energy stores (such as weight training) then follow it with slower engergy stores (cardio) you will be in the fat burning zone a little quicker.  Today there are several different ways to put together a good workout so that is just one example.  Also remember that muscle is active and burns fat for us.  More muscle, more fat burn.

Not necessarily. Our body has a unique ability to have large storage supplies of glycogen which is our primary fuel source. So even if you are exercising on an empty stomach your body will continue to use stored glycogen as fuel source. In addition to this your body has the ability to create energy more readily than it can breakdown fat for energy. Burning fat will gradually occur overtime by expending more energy than you consume in a given day.

Sari Greaves
Nutrition & Dietetics
Working out while hungry may fly in the face of conventional wisdom, but many athletes and gym-goers push themselves on empty stomachs in the belief they'll burn more fat.

The idea, advocated in popular fitness books over the past decade, is that exercising on an empty stomach forces the body to dip into fat stores for fuel instead of the carbohydrates quickly available from a pre-workout meal or snack. But while it seems to make sense, research shows that exercising in this way doesn't offer any benefit and may even work against you.

After reviewing years of research on the subject, a report published in Strength and Conditioning Journal concluded that the body burns roughly the same amount of fat regardless of whether you eat before a workout. But you're likely to lose muscle by exercising in a depleted state, the report found, and without fuel to aid the workout, exercise intensity and overall calorie burn will be reduced.

One of the studies reviewed in that report looked at cyclists when they trained after eating and when they trained while fasting. When they trained with nothing in their stomachs, about 10 percent of the calories they burned came from protein, including lost muscle, the researchers wrote.

In a separate study published in 2002, scientists found an additional benefit from a pre-workout meal: Healthy women who consumed 45 grams of carbohydrates before their workouts ended up eating less throughout the remainder of the day.

Exercising on an empty stomach does not help burn more fat.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.