Happy Monday All!
I’m sure at one point or another, you have heard about the “fat-burning zone.” To burn more fat, you should workout at a low-intensity, right?
Well, not exactly. This theory is based on relative percentages. When working out at a low intensity, a larger percentage of your burned calories comes from fat. If you increase your workout intensity, your fuel source switches from fats to carbohydrates, meaning at higher intensities, carbohydrates make up the majority of calories burned.
Why is there a difference? Our bodies can’t use fats directly for energy. In fact, carbohydrates are the only fuel source that our bodies can use DIRECTLY for energy. For example, to use fats as an energy source, we first have to mobilize our fat stores and then convert it to another compound. This takes time! With carbohydrates, we can use a pathway called non-oxidative glycolysis to convert glucose into energy rapidly. We don’t need oxygen to do this, and we can use our glycogen stores in our muscles.
On a physiological level, it makes sense to think that you should workout at lower intensities to burn more fat, especially if you are trying to tone up. But, there is a catch. If you are working out at a lower intensity, you are also burning LESS calories. This can hinder your weight loss progress. Weight loss is all about being in a caloric deficit. Therefore, even if you are burning a higher percentage of fat working out at a lower intensity, you probably aren’t burning a large number of total calories. Think about it: if you are only burning 200 calories per exercise session, you most likely won’t see the scale change anyways!
Moral of the story: don’t be afraid to workout at higher intensities! You will burn more total calories and achieve your weight loss goals quicker.
What have you heard about the “fat-burning zone?”