Glycogen – the main carbohydrate for muscles

Glycogen is the muscle (and liver) store of carbohydrates used as the primary source of energy during exercise. The source of glycogen is glucose consumed with food (or with sports drinks).

The more a person exercises, the more efficiently their body stores carbohydrates in the muscles in the form of glycogen – whereas with a sedentary lifestyle, they go to fat. In addition, fat burning is also achieved after the depletion of glycogen depots.

What is glycogen?

Glycogen is a type of carbohydrate stored in the human body. The substance is sometimes called “animal starch” because glycogen is similar in structure to ordinary starch and consists of hundreds or thousands of glucose molecules linked together.

The source of glycogen is carbohydrates from food. Recall that the body cannot store glucose in its pure form – its high content in cells creates a hypertonic environment, leading to an influx of water and the development of diabetes. On the other hand, glycogen is insoluble in water.

After the blood glucose level drops (for example, a few hours after eating or during physical training), the body begins to break down the glycogen stored in mice into glucose, becoming a source of fast energy.

Functions of glycogen:

• Carbohydrate digestion product
• The main fuel for muscle work
• Source of fast energy for the body

Glycogen and glycemic index of food

In the process of digestion, carbohydrates from food are broken down to glucose (fats and proteins cannot be converted into it) – after which it enters the bloodstream. Glucose can be used by the body either for current metabolic needs or be converted to glycogen – or to fat.

The lower the glycemic index of a food, the better the carbohydrates it contains are converted to glycogen. Despite the fact that simple carbohydrates increase blood glucose levels as quickly as possible, a significant part of them is converted into fat reserves.

In turn, the energy of complex carbohydrates, obtained by the body gradually, is more fully converted into glycogen contained in the muscles. That is why a diet for gaining muscle mass involves the use of carbohydrates with low and medium GI.

Where is glycogen stored?

In the body, glycogen accumulates mainly in the liver (about 100-120 g) and in muscle tissue (from 200 to 600 g). It is believed that approximately 1% of the total muscle weight falls on this substance. An unathletic person can have glycogen stores of 200-300 g, and a muscular athlete – up to 600 g.

It is also important that the liver glycogen stores are used to cover the energy needs of glucose throughout the body, while the muscle glycogen stores are available exclusively for local consumption. In simple terms, during squats, the body uses the muscle depot of the legs, not the biceps.

Functions of glycogen in muscles

More precisely, glycogen does not accumulate in the muscle fibers themselves, but in the sarcoplasm, the nutrient fluid that surrounds them. Muscle growth is associated with an increase in the volume of this particular nutrient fluid – in their structure, the muscles are similar to a sponge that absorbs sarcoplasm to increase in size.

Regular strength training has a positive effect on the size of glycogen depots and the amount of sarcoplasm, making the muscles visually larger and more voluminous. At the same time, the number of muscle fibers is set primarily by the type of physique and practically does not change during a person’s life, regardless of training – only the body’s ability to accumulate more glycogen changes.

Glycogen in the liver

The liver is the body’s main filtering organ. In particular, it processes carbohydrates supplied with food – however, the liver can process no more than 100 g of glucose at a time. In the case of a chronic excess of fast carbohydrates in the diet, this figure rises.

As a result, liver cells can convert sugar into fatty acids. In this case, the stage of glycogen is excluded, and fatty degeneration of the liver begins.

Influence on muscles – biochemistry

Successful training for muscle recruitment requires two conditions – firstly, the presence of sufficient glycogen stores in the muscles before training, and, secondly, the successful restoration of glycogen depots at the end of it.

By doing strength training without glycogen stores (or without BCAAs) in the hope of “getting shredded,” you are forcing your body to burn muscle. For muscle growth, it is not so much protein intake that is important, but the presence of a significant amount of carbohydrates in the diet.

In particular, a sufficient intake of carbohydrates immediately after the end of the workout during the “carbohydrate window” is necessary to replenish glycogen stores and stop catabolic processes. In contrast, you can’t build muscle on a carbohydrate-free diet.

How to increase glycogen stores?

Glycogen stores in the muscles are replenished either with carbohydrates from food or by using a sports gainer (a mixture of protein and carbohydrates in the form of maltodextrin). As we mentioned above, in the process of digestion, complex carbohydrates are broken down into simple ones; first, they enter the blood in the form of glucose, and then they are processed by the body into glycogen.

The lower the glycemic index of a particular carbohydrate, the slower it releases its energy into the blood, and the higher its percentage of conversion is into glycogen depots, and not into subcutaneous fat. This rule is of particular importance in the evening – unfortunately, simple carbohydrates eaten at dinner will go primarily to belly fat.

What increases the glycogen content in muscles:

• Regular strength training
• Eating low glycemic carbs
• Taking a mass gainer after a workout
• Revitalizing muscle massage

Impact on fat burning

If you want to burn fat through training, remember that the body first uses glycogen stores and only then moves on to fat stores. It is on this fact that the recommendation is based that an effective fat-burning workout should be carried out for at least 40-45 minutes with a moderate pulse – first the body spends glycogen, then switches to fat.

Practice shows that fat burns fastest when doing cardio in the morning on an empty stomach or using intermittent fasting. Since in these cases, the level of glucose in the blood is already at a minimum level, from the first minutes of training, glycogen stores from the muscles (and then fat) are spent, and not glucose energy from the blood at all.

Glycogen is the main form of glucose energy storage in animal cells (plants do not have glycogen). In the body of an adult, approximately 200-300 g of glycogen accumulates, stored mainly in the liver and muscles. Glycogen is wasted during strength and cardio training, and for muscle growth, it is extremely important to properly replenish its reserves.