Back in the 90’s, I recall reading the advice that skipping food before an early morning workout forces the body to utilize fat stores for fuel right away. At the time (and not knowing better), this sounded reasonable. I was never able to stick to that “rule,” mainly because I was so dog-on hungry in the morning and would also return from my workout with the jitters from low blood sugar if I didn’t eat beforehand. I ignored that advice, and when I returned to school some years later to complete my BS in Exercise Science, I learned that the body always uses carbohydrate for fuel, and also requires carbohydrates to burn fat. So much for the aforementioned myth.

Here’s the deal: The body uses carbohydrates first. No exception. The chemical reactions that support this energy-making process occur rather rapidly. This is what enables you to run up the stairs in response to hearing a child cry for help. Think of carbs as “fast fuel.”

The process of turning carbohydrate into fuel is called glycolysis. Now, one of the by-products of glycolysis can be sent through another series of much slower chemical reactions called the Kreb’s Cycle. This particular cycle produces fuel for sustained events. Think distance running. Fat doesn’t enter the equation until it is first broken down through a process called beta-oxidation. So it’s not like if you skip breakfast, your body will use fat for fuel instead. It just doesn’t work that way. (Fitness Faux Pas)

My advice: eat a quality carbohydrate, or small snack that has a ratio of 3:1 or 4:1 carbohydrate to protein, and you’ll fuel your workout, as well as enable the fat-burning process to continue (I’d say “begin,” but we’re always burning fat, as long as we’re consuming sufficient calories, of course.)

So let’s recap:

Do we burn fat exclusively if we skip breakfast and then work out? No.

Do we burn MORE fat if we skip breakfast and then work out
No

Do we NEED breakfast (or some form of food) before a morning workout? YES! Emphatically, YES!! (Food is your friend)