Glycogen depletion

The Fat Burning Mechanism – Glycogen Depletion

A large number of people go to the gym, hoping they will burn fat and lose excess weight,  without even knowing how the “fat-burning” mechanism actually works. If you want to lose fat, it is absolutely important to know what the body uses as energy source.

What is glycogen

Our body uses glycogen as a primary source of energy. Glycogen is actually the storage form of glucose (carbohydrates) in animals and humans. The liver and cells of the skeletal muscles is where glycogen is made and primarily stored primarily.

When there is no glycogen available, the body will reach for its secondary energy source – stored fat and muscle protein.

An average person has to do about 30-40 minutes of moderate intensity cardio in order to burn the stored glycogen. This means that if you do cardio for an hour, you are burning fat only the last 20 to 30 minutes, while the first 30-40 minutes you are only depleting your glycogen stores.

Glycogen depletion for fat loss

There are a few ways to burn mostly fat when you do your cardio workout:

Do morning cardio or fasted cardio sessions.

When your body goes longer periods without food (like fasting or 8-9 hour sleep) it depletes glycogen in order to sustain itself.This is why morning cardio will burn mostly fat.It is a good idea to take a protein shake or BCAA prior to the workout to prevent muscle breakdown.

Work with weights before the cardio session.

Weight training is a glycogen depleting activity and it is a good practice to do your weight workout before the cardiovascular workout.

Modify your diet and lower the amount of carbohydrates you are consuming.

This way the body will not have excess carbohydrates that can be stored as glycogen, so even light activities will burn fat.Many diets are built around the idea of reduction of carbs – just take the Atkins diet for example (lots of protein and fats, but almost no carbs)

Knowing what glycogen is and how your body uses it will certainly help you maximize your cardio sessions to burn the maximum amount of fat, but this is not the only factor that comes into play when trying to lose fat.  Below are a few other tips that will help you to lose fat:

– Keep a training journal and record your meals and the calories for each meal. The journal will help you tailor your meals and workouts for you and help you find out what works best for you over time.

– Avoid empty calorie sources such as fruit juices, sodas and sweets.Eliminating empty calories can be
the easiest and quickest way to cut calories out of your diet.

– Drink about a gallon of water everyday! Water helps metabolize the fat and drinking cold water is actually a calorie consuming process. In order to be absorbed, water will first be heated by the body, burning calories in the process.

– Don’t be lazy. Even small things matter. Walking the dog or climbing the stairs will also add up to the whole fat burning process.

For the latest news and updates join our 1 Million fans on Facebook, Twitter and Pinterest.


  1. Mrinal Kanti Banik
    • Himanshu saxena
  2. Heather

Leave a Reply