Glycogen is a polysaccharide (complex carbohydrate) of glucose (Glc) which functions as the primary short term energy storage in animal cells.
It is made primarily by the liver and the muscles, but can also be made by the brain, uterus, and the vagina.
Glycogen forms an energy reserve that can be quickly mobilized to meet a sudden need for glucose, but one that is less compact than the energy reserves of triglycerides (fat).
Only the glycogen stored in the liver can be made accessible to other organs. In the muscles, glycogen is found in a much lower concentration (1% of the muscle mass), but the total amount exceeds that in the liver.
Small amounts of glycogen are found in the kidneys, and even smaller amounts in certain glial cells in the brain and white blood cells. The uterus also stores glycogen during pregnancy to nourish the embryo.
Function and regulation of liver glycogen
As a meal containing carbohydrates is eaten and digested, blood glucose levels rise, and the pancreas secretes insulin. Glucose from the portal vein enters the liver cells (hepatocytes). Insulin acts on the hepatocytes to stimulate the action of several enzymes, including glycogen synthase. Glucose molecules are added to the chains of glycogen as long as both insulin and glucose remain plentiful. In this postprandial or “fed” state, the liver takes in more glucose from the blood than it releases.
After a meal has been digested and glucose levels begin to fall, insulin secretion is reduced, and glycogen synthesis stops. About four hours after a meal, glycogen begins to be broken down and converted again to glucose. Glycogen phosphorylase is the primary enzyme of glycogen breakdown. For the next 812 hours, glucose derived from liver glycogen will be the primary source of blood glucose to be used by the rest of the body for fuel.
Glucagon is another hormone produced by the pancreas, which in many respects serves as a counter-signal to insulin. When the blood sugar begins to fall below normal, glucagon is secreted in increasing amounts. It stimulates glycogen breakdown into glucose even when insulin levels are abnormally high.
Glycogen in muscle and other cells
Muscle cell glycogen appears to function as an immediate reserve source of available glucose for muscle cells. Other cells that contain small amounts use it locally as well. Muscle cells lack glucose-6-phosphatase enzyme, so they lack the ability to pass glucose into the blood, so the glycogen they store internally is destined for internal use and is not shared with other cells, unlike liver cells.
Glycogen debt and endurance exercise
Due to the body’s inability to hold more than around 2,000 kcal of glycogen, long-distance athletes such as marathon runners, cross-country skiers, and cyclists go into glycogen debt, where almost all of the athlete’s glycogen stores are depleted after long periods of exertion without enough energy consumption. This phenomenon is referred to as“hitting the wall” or “bonking”. In marathon runners it normally happens around the 20 mile (32 km) point of a marathon, where around 100 kcal are spent per mile, depending on the size of the runner and the race course. However, it can be delayed by carbohydrate loading before the race. When experiencing glycogen debt, athletes often experience extreme fatigue to the point that it is difficult to move.
Disorders of glycogen metabolism
The most common disease in which glycogen metabolism becomes abnormal is diabetes, in which, because of abnormal amounts of insulin, liver glycogen can be abnormally accumulated or depleted. Restoration of normal glucose metabolism usually normalizes glycogen metabolism as well. In hypoglycemia caused by excessive insulin, liver glycogen levels are high, but the high insulin level prevents the glycogenolysis necessary to maintain normal blood sugar levels. Glucagon is a common treatment for this type of hypoglycemia. Various inborn errors of metabolism are caused by deficiencies of enzymes necessary for glycogen synthesis or breakdown. These are collectively referred to as glycogen storage diseases.
Preserve glycogen when you exercise and use your body fat for energy
Your body has two primary sources of energy – glycogen and fatstored by the body.
Glycogen is easily burned in a short period of time and serves as a source of stamina in events that require a burst of energy.
The disadvantage with this is the limited amount of glycogen reservesyour body has. A mere 450 grams (approximately 1,800 kilo calories) of glycogen is stored in your body (this may vary according to individual body types).
Your stores of glycogen are not sufficient to provide energy during exercise of long duration.
Conversely, fat is stored in abundance by the body, although it is generally difficult to convert into energy, requiring large amounts of oxygen to do so.
Even the slimmest athlete can use their low body fat for energy!
Take a marathon runner weighing 130lbs with only about 5% body fat. This calculates to approximately 27,000 kilo calories of energy reserves. This is enough energy to run a full marathon consuming 3,000 kilo calories, nine times over!
This makes fat an abundant source of energy and stamina for endurance sports.
Enter Hornet Juice…
Hornet Juice Metabolizes Fat for Energy from the Start of Exercise
The comprehensive study of the giant hornet revealed that its incredible feats of endurance were because it used its store of fat for energy, due entirely to the Hornet Larval Saliva that it ingested, which promoted this fat burning process.
Hornet Juice has been developed to achieve this same fat for fuel effect with its optimum combination of 17 amino acids.
Hornet Juice activates the metabolism of fat for energy right from the start of your physical activity. This results in your glycogen being conserved, enabling you to maintain a steady pace to the very end. You will have plenty of energy in reserve and be able to call on bursts of power when you most need them.
The illustration below shows Normal Energy Consumption versus Energy Consumption Using Hornet Juice:
Fat takes a long time to metabolize before it becomes a source of energy during endurance sports. If however fat can be utilized as energy from the commencement of exercise then glycogen will be preserved. This will allow a steady pace to be maintained throughout your training and/or competition event, with bursts of power able to be called upon when needed. This is the feature of Hornet Juice, it functions by activating the metabolism of fat into energy.