Glycogen Metabolism refers to the synthesis and breakdown of glycogen. Glycogen is a branched polymer that is the primary form of short-term storage for carbohydrates in animal cells.
Did you know that your body can store around 18,000 calories of energy? This is known as your metabolic rate. It is the energy your body uses at rest (the amount of energy you use while sitting still). The metabolic rate is determined by the amount of muscle mass you have. The more muscle you have, the higher your metabolic rate will be. Conversely, if you are undernourished or don’t eat enough food, it will slow you down and make it harder for you to lose weight. But how does this relate to glycogen? When we store excess carbohydrates as glycogen in our muscles, our metabolic rate increases, making it easier for us to lose weight. We will look at everything you need to know about glycogen metabolism below.
What is glycogen?
Glycogen is a carbohydrate that occurs in the body in limited quantities. It is the storage form of glucose, which is a simple sugar. Your body can convert glycogen into glucose only when you need it for energy.
Your muscles and liver store glycogen for energy during exercise and when your body needs extra fuel. Glycogen is a complex molecule made up of glucose molecules bonded. The process of converting glycogen into glucose is called glycogenesis.
The body stores about 1 pound (500 grams) of glycogen in the liver and another pound (500 grams) in skeletal muscle tissue. If you eat more carbohydrates than your body needs at one time, excess blood sugar gets converted into glycogen and stored in your liver and muscle cells until they are needed. Glycogen is broken down into individual glucose molecules when your body needs energy—such as during exercise or fasting—or when there isn’t enough insulin present or available to allow cellular uptake of blood sugar from the bloodstream (insulin resistance).
How is Glycogen Metabolism Used in Weight Loss?
One of the ways that glycogen metabolism is used in weight loss is by increasing our metabolic rate. It does this by providing fuel for your muscles and body to use. Another way it is used in weight loss is that it lets us tell our brain we are full. When we eat, the stomach sends signals to our brain about what we ate and how much. If the stomach signals to the brain that there is enough food available, it doesn’t send signals telling us when to stop eating.
This means we could overeat if we do not have enough glycogen stored in our muscles. The last way glycogen metabolism helps with weight loss is that it provides fuel for anaerobic exercise like high-intensity interval training (HIIT). Anaerobic exercise is training where you work at an extremely high intensity for a short period before returning.
How Does Glycogen Storage Affect the Metabolic Rate?
When we store excess carbohydrates as glycogen in our muscles, our metabolic rate increases, making it easier for us to lose weight. The more muscle mass you have, the higher your metabolic rate will be. But how does this work? It all comes down to hormones called glucagon and insulin. Glucagon is a hormone that tells your body to store energy and increase your metabolic rate when you need it most. Insulin, on the other hand, is a hormone that prevents the release of stored energy. When the body stores too much energy as fat instead of carbohydrates, insulin sensitivity becomes decreased and thus leads to insulin resistance. This means that people with high body fat are at an increased risk of diabetes and heart disease because their bodies do not use glucose efficiently anymore.
What is glycogen used for?
Glycogen is stored in the liver and muscles. It is the body’s primary energy source, providing glucose most needed, such as during exercise.
After you eat a meal, glucose levels rise in your bloodstream. To keep blood sugar levels consistent, your pancreas secretes insulin, which helps move glucose into muscle cells and fat tissue (stored as glycogen). Any excess blood sugar is turned into glycogen so that it can be used whenever needed by other organs like the brain or kidneys.
Glycogen stored in muscle tissue is broken down during exercise to provide energy for your muscles to contract against resistance and keep moving—without adequate stores of glycogen, you would tire out quickly! After training sessions or races lasting longer than 2 hours (or shorter events but with high intensity), athletes replenish their glycogen stores by eating high-carbohydrate foods such as bananas or pasta immediately after completing their activity to prevent “bonking” or becoming depleted from a lack of fuel sources for working muscles.
How is glycogen broken down?
Glycogen is broken down into glucose. Glucose is broken down into pyruvate. Pyruvate is broken down into acetyl-CoA. Acetyl-CoA is broken down into acetyl-CoA, the first step of aerobic respiration (the breakdown of food to produce energy).
How exactly does a cell “know” when to break down glycogen stores?
The answer is that hormones control the rate of glycogen breakdown. There are two main hormones involved in this process: insulin and glucagon. Insulin stimulates glycogen breakdown, whereas glucagon inhibits it. The pancreas releases these two hormones into your bloodstream after you eat a meal or snack high in carbohydrates and sugar.
The process of turning carbohydrates into energy happens in a few steps, and the final product of this process is ATP.
Glycogen is a type of carbohydrate that is stored in the liver and muscles. When these stores are depleted, your body can draw on glycogen as energy. The process by which glycogen is converted into glucose and ATP is known as glycolysis, which occurs in the cytoplasm of cells. Glycolysis occurs in several steps.
- Glucose is broken down into two separate carbon molecules that contain three phosphate groups each; this process produces two triose phosphates (3 carbons long), one dihydroxyacetone phosphate (2 carbons long), and one ATP molecule.
- The 2 triose phosphates undergo an oxidation reaction with an electron driven by NAD+/NADH from step 1 above; when this happens, it produces a pyruvate molecule plus another ADP molecule.
What is glycogenolysis and glycogen synthesis?
Glycogenesis is the conversion of glucose into glycogen. Glycogen is a storage form of glucose that your body can use. The liver and skeletal muscles store most of the body’s glycogen, but it’s also present in the brain and other organs.
Glycogenolysis occurs in response to hormonal signals, including epinephrine (adrenaline) and glucagon, as well as in response to low blood glucose levels (hypoglycemia). The latter triggers the release of glucagon from the pancreas, which binds to liver cells and stimulates their glycogenolytic activity.
Glycogen synthesis is the process by which glucose molecules are added to chains of glycogen. The process involves several enzymes that catalyze reactions that convert individual glucose units into strands of glycogen.
The Benefits of a High-Glycogen Diet
Understanding that a high-glycogen diet can help you get into shape is important. Exercise can also help prevent illness and disease if you have a low metabolic rate. Both muscle-building and health benefits are associated with a high-glycogen diet. Scientific evidence also says a high-glycogen diet is linked to increased brain function. It helps improve memory and cognitive performance, which means it’s great for cognitively demanding jobs like working in sales or finance. In addition to all its benefits, there’s also evidence that a high-glycogen diet can help burn fat more effectively than diets that limit protein intake.
A study published as early as 2006 concluded that the increase in protein intake from 12 percent to 20 percent increased glycogen stores by about 35 percent and decreased fat stores by about 30 percent. This would suggest that your body will burn more fat when you eat protein at a higher percentage of your overall caloric intake than just carbohydrates alone.
Limitations of a High-Glycogen Diet
A high-glycogen diet can make it easier for you to lose weight, but it has its limitations. The downside is that you could have serious health problems if your body doesn’t have enough calories to burn from the carbs you’re storing in your muscles. When glycogen stores are too high, it can happen that you don’t get the right number of calories or vitamins and minerals. You might be unable to maintain a healthy caloric intake because your metabolism would slow down and stop functioning properly.
If you decide to adopt a high-glycogen diet, remember that muscle glycogen is only a limited resource. If you don’t eat enough food, your body will start breaking down muscle tissue for energy instead of using carbohydrates. So, remember: if you use a high-glycogen diet to help you lose weight, make sure there are enough calories for your body.
Should You Eat a High-Glycogen Diet to Lose Weight?
If you’re trying to lose weight, the answer is no because there isn’t any evidence that supports a high-glycogen diet that will help you lose weight. You should eat a well-rounded diet that includes protein, fat, and carbs. When it comes to losing weight, it doesn’t matter whether you have low or high levels of muscle mass, as long as your calories are in check. And don’t forget what Dr. Kaayla Daniel says: “There is no magic number for how many grams of carbs you want to eat daily.”
If you want to lose weight, eat fewer calories than your daily caloric needs, so there is a deficit between what you consume and what your body needs. If you want to gain weight, the same holds, but the opposite applies: eat more than your daily caloric needs, so there is an excess between what you consume and what your body needs.
Glycogen is a polysaccharide (chain of glucose molecules)
Glycogen is a polysaccharide (chain of glucose molecules) that stores energy in the liver and muscles in animals. It’s one of two types of carbohydrates stored as glycogen—the other being starch. In plants, it serves as long-term storage for carbon dioxide from photosynthesis.
Glycogen is made up of a single glucose molecule with branching chains resulting in long chains of glucose units.
Glycogen is a polymer of glucose residues. It consists of a central chain of glucose molecules connected by alpha 1-4 glycosidic bonds, meaning that each molecule has one end (the C-1 carbon) that can form an OH group from the next molecule’s C-4 carbon. This results in a branched structure wherein each branch comprises one glucose unit.
Insulin is needed for muscle cells to take up glucose from the blood and store it as glycogen.
Perhaps you’ve heard of insulin before. It’s a hormone that helps regulate the storage and usage of glucose in the body. If you haven’t, here’s what you need to know about it:
- Insulin is a storage hormone. When your body needs to store glucose, it releases insulin into your bloodstream. The purpose is for your muscles and liver cells—which have receptors for this hormone—to take up glucose from the blood and convert it into glycogen (a form of stored energy).
- Insulin isn’t just important for storing glucose. It also helps store glycogen, formed when many individual carbohydrate units are joined together into one long chain. Glycogen is stored in muscle tissue and the liver as an emergency energy source while waiting for more carbs to arrive via digestion or absorption through the intestinal wall (aka eating).
In humans, the process starts with a series of reactions that occur primarily in the liver, kidneys, and intestines.
- Glycogenolysis is the process of splicing enzymes to break down glycogen into glucose, which is then used as fuel within the cell.
- Glycogenesis is the process of creating new glycogen molecules from glucose through a series of reactions that occur primarily in the liver and kidneys, and intestines.
Glycogen metabolism can be controlled through dietary choices we make daily
As you learned in the previous section, glycogen is a polysaccharide, a chain of glucose molecules. It is mainly stored in the liver and muscles, serving as a storage form of energy. When your body needs extra energy to perform any task that requires greater physical effort than normal—such as exercise or just walking around all day—it breaks down glycogen into glucose which can then be used for energy.
Glycogen is primarily stored in the liver and muscles but can also be found in a small number of cells called red blood cells (RBCs). For glucose to enter muscle cells and become glycogen, it must first be broken down into glucose-6-phosphate by phosphoglucomutase. After this step, glycogenesis begins with a series of reactions primarily carried out by glycogen synthase and ends with the formation of glucose-1-phosphate.
During digestion, amylases break down starch into maltose which is then converted into glucose by maltase. On top of these processes occurring within our bodies every day, many factors affect how much glycogen each person needs depending on lifestyle choices such as dieting or exercising regularly.