Fat Adapted Runner

So you want to become fat adapted? Let’s discuss exactly what that means.

Fat adaptation is the metabolic reorchestration from a predominant fuel source of glucose to a predominant fuel source of fat.

This is the normal, preferred metabolic state of the human. Before the food pyramid created the obesity epidemic, humans were in an constant yearly cycle of fat adaptation, based on factors such location, climate, season and food supply.

Even if you are a very well trained runner with 2000 calories of muscle glycogen stored, if you are a sugar burning, who burns 1000 calories/hour, you’ll obviously run out of fuel at beyond 2 hours. Even if you’re consuming able to consume 300 calories/hour, there’s still a 700 calorie deficient. You don’t need to replace everything you burn, but the inability to tap into our fat reserves is what causes a ‘nutritional bonk’ or ‘hitting the wall’. When you become fat adapted you will never run out of fuel and have an in-built glycogen sparing effect, so this carbohydrate stored in the muscle is available to support high intensity (where it is most required).


For support becoming a fat adapted athlete, sign up for one of the following programs:

To discuss this further, please book your complimentary 15-minute consultation here to speak to team at The Natural Nutritionist.