In the last few decades, insulin has made a mini-revolution in bodybuilding. Professional bodybuilders have become even bigger. Some of them gain up to 10 kg in mass per season after reaching a plateau.
The general audience is led to believe that such colossal results are related to the use of new secret drugs or genetic engineering.
The truth is that bodybuilders have discovered a powerful anabolic hormone produced in the body – insulin. Its advantages are that it is legal (as a diabetic medication) and very cheap.
In this article, we will discuss the mechanism of insulin action in sports and bodybuilding, and you will learn why many athletes today, without having diabetes, lead a lifestyle similar to that of diabetics…
Main thoughts:
Insulin not only helps stimulate muscle growth.. without it, muscle growth is essentially impossible
For muscle mass gain, a high level of insulin in the blood is important
What is insulin?
Insulin is a hormone produced in the pancreas that performs multiple functions, collectively making it one of the main, if not the most important, anabolic hormones in the human body.
Insulin regulates the metabolism of carbohydrates, fats, and proteins in the body.
The main function of insulin in the body is to maintain a safe and stable level of glucose (sugar) in the blood. In the process of doing so, depending on certain conditions (see below), favorable conditions are created either for muscle growth or for an increase in body fat.
Moreover, insulin itself positively influences protein synthesis in the body, including muscle proteins, promoting more effective muscle mass growth.
A deficiency of insulin has the opposite effect – a catabolic one, i.e., it leads to the breakdown of muscle mass.
Insulin is one of the most anabolic, i.e., beneficial for muscle growth, hormones in the human body. It regulates the metabolism of carbohydrates, fats, and proteins, creating conditions for muscle growth as well as.. fat mass gain.
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Insulin in Sports and Bodybuilding
In bodybuilding, the anabolic properties of insulin are of primary interest, i.e., its ability to enhance the efficiency of processes that directly affect muscle mass growth.
Its anabolic properties may even be stronger than those of the growth hormone.
According to the WADA (World Anti-Doping Agency) classification, insulin is a banned doping substance, but it is one of the most popular among professionals and bodybuilding enthusiasts.
“It cannot be detected during a doping test. It simply improves athletic performance. It can just kill…” – this is how a news article about insulin begins on one of the information portals.
The use of insulin in sports is one of the latest deadly trends. Bodybuilders often use it in combination with steroids and growth hormone for maximum stimulation of muscle growth and overcoming physiological plateaus in mass gain. It is estimated that one in four bodybuilders “on steroids” also takes insulin. This is the secret to incredible size.
Insulin helps save lives for people with diabetes. Its use by healthy individuals (= athletes) can end in coma and death.
In bodybuilding, insulin helps to fill muscles with energy and nutrients during intense workouts, preventing muscle catabolism.
The International Olympic Committee prohibits its use. Although it is one of the few doping substances that are impossible to detect. Many bodybuilders take it right up to competitions and still pass doping tests.
Insulin in sports is typically used in combination with steroids and growth hormone to overcome physiological plateaus in mass gain. Its anabolic properties may even be stronger than those of growth hormone.
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The mechanism of insulin action for muscle mass gain in bodybuilding
In bodybuilding, insulin is used to increase endurance and build muscle mass.
When we eat something sweet, insulin is released by the pancreas and facilitates the entry of glucose into cells (including muscle cells) for use as energy.
The anabolic properties of insulin are explained by the fact that, in addition to glucose, it provides better delivery of amino acids (= building materials) and some minerals into muscle cells and enhances muscle protein synthesis.
Glucose is an energy molecule. If its concentration in the blood exceeds the body’s current energy needs, it is converted into glycogen. Glycogen is an energy storage that is “opened” after using the glucose present in the blood and is used to fuel muscles during training.
Dr. Sonksen from St Thomas’ Clinic in London, in his article on the use of growth hormone and insulin in sports, states: “Since in most sports the result is determined by the amount of glycogen in the muscles, increasing its content directly affects the outcome.”
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The action of insulin for muscle mass gain in bodybuilding is explained by the following mechanisms:
1 Insulin stimulates muscle protein synthesis
Insulin stimulates protein synthesis (and, consequently, muscle mass growth).
How?
Muscles are made up of muscle proteins. These proteins are produced by ribosomes. The mechanism of protein synthesis by ribosomes is triggered by insulin. (Ribosomes, according to Wikipedia, are complex molecular machines that contain the coded information on how to create proteins.)
One of the scientists provides the following explanation of the process:
“It is not entirely clear how, but insulin activates the ribosomal machine for protein production. In its absence, ribosomes simply stop working; it acts like a switch.”
Does this mean that insulin “helps” to build muscle? No. It means that without insulin, it is impossible.
Insulin not only helps stimulate muscle growth… without it, it is fundamentally impossible
2 Insulin prevents muscle catabolism
Another function of insulin that is beneficial in bodybuilding is that it prevents muscle breakdown. Its anti-catabolic function is just as important for gaining mass as its anabolic effect.
Every day, our body creates and breaks down proteins. To gain muscle mass, it is necessary for more protein to be synthesized than is broken down. Insulin helps shift this ratio in the right direction by facilitating more effective delivery of amino acids into muscle cells.
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3 Insulin improves the delivery of amino acids into muscle cells
Insulin facilitates the entry of amino acids into muscle cells, making the process of their recovery and growth more effective.
Among all amino acids, BCAA amino acids are particularly significant due to their colossal role in muscle mass gain.
4 Insulin enhances glycogen synthesis, making muscles bulkier
Insulin increases the activity of certain enzymes that stimulate glycogen synthesis. This means that it helps store glucose in muscle cells, thereby improving efficiency, recovery, and literally increasing muscle size.
The accumulation of glycogen in muscles makes them denser and bulkier, as it retains water: every gram of glycogen “binds” approximately 2.7 grams of water.
Insulin stimulates glycogen accumulation in muscles, making them denser and bulkier by retaining more water
We have understood the anabolic properties of insulin in bodybuilding. Now let’s look at the other side of the coin…
Cons of using insulin in bodybuilding: impact on fat loss
The same mechanism that explains the anabolic properties of insulin is the reason for another, but negative side effect of its use in bodybuilding – gaining fat mass.
When we consume a lot of carbohydrates and the glycogen stores in the liver and muscles are filled, the excess sugar in the blood is then sent to fat stores with the help of insulin.
That is, alongside stimulating muscle growth, insulin accelerates the process of lipogenesis (fat formation).
This is particularly important for those sports where weight categories are considered: using insulin can easily cause one to fall out of their category.
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The mechanism of insulin action in gaining fat mass is as follows:
1 Insulin converts excess carbohydrates into fat
Carbohydrates, or more specifically glucose, are the primary source of energy for cells.
Insulin “opens” cell membranes for glucose to enter them.
If there is too much glucose in the blood, the excess beyond the current energy needs is first stored in glycogen stores in the liver and muscles, and after they are filled, it is sent for storage as fat.
2 Insulin prevents the use of fats for energy
The main function of insulin is to supply energy through carbohydrates, not fats. Carbohydrates (glucose) are the primary source of energy for all cells.
This means that as long as there are carbohydrates in the system, energy for cell functioning will be derived from them, while fat stores will remain closed.
Some weight loss diets are based on this principle to activate the fat-burning process. In particular, intermittent fasting and the ketogenic diet.
In the case of intermittent fasting, food is consumed only within an 8-hour window during the day. The result of such a time restriction, during which eating is allowed, is the complete depletion of glycogen stores over the remaining 16 hours of the day and the initiation of the process of using fat for energy.
On the ketogenic diet, carbohydrates are almost completely excluded from the diet, which keeps glycogen stores always unfilled, leaving the body no choice but to burn fat for energy.
3 Insulin blocks the action of the enzyme that activates the fat-burning process
This enzyme is called hormone-sensitive lipase and it is responsible for breaking down fat molecules.
Fat burning always begins with its breakdown to the level of fatty acids, which are then used for energy. It is clear that disrupting the first stage hinders the weight loss process.
4 Insulin promotes the synthesis of fatty acids
Insulin increases the synthesis of fatty acids in the liver, from which the process of lipogenesis or the creation of body fat begins.
A high level of insulin negatively affects weight loss. It prevents the use of fats for energy and promotes the formation and accumulation of fat.
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How to use insulin in bodybuilding for mass gain or weight loss (without drugs)?
The anabolic properties of insulin in bodybuilding can be utilized in two ways: through the construction of a proper diet and injections.
Since insulin secretion is a response of the body to carbohydrate intake, by regulating their content in food, one can manage insulin levels: when it needs to be raised and when it needs to be lowered.
Injectable insulin preparations are used in bodybuilding for a more significant and rapid effect on its blood levels at critical moments.
Insulin for muscle mass gain
To ensure muscle growth, it is necessary to maintain a high level of insulin in the blood throughout the day, especially during, before, and immediately after workouts.
This is why, according to the principles of proper nutrition for muscle mass gain, carbohydrates are just as important as protein, although a very common misconception is that only protein is responsible for mass gain, while carbohydrates should be minimized to achieve a dry physique.
A high level of insulin in the blood is important for muscle mass gain.
Insulin for weight loss
If the goal is to lose weight, it is necessary to limit insulin levels throughout the day. This is why many diets are based on the principle of completely excluding fast carbohydrates (sweets).
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However, an intelligent approach is important. “The less, the better” does not work here, especially for physically active individuals.
A lack of carbohydrates during exercise will inevitably lead to muscle weakness, decreased endurance, and can also cause muscle catabolism: muscle mass will be lost along with fat mass.
To lose weight, it is necessary to limit insulin levels in the blood to stimulate fat burning; but without fanaticism: insulin is necessary to avoid a catabolic state and to provide energy for workouts.
Insulin for muscle mass gain and weight loss
This is the ideal goal for most athletes in fitness and bodybuilding. Almost all athletes strive for it.
In bodybuilding, it is believed that it is impossible to burn fat and gain muscle mass simultaneously. This is why in professional sports, there is a constant alternation between bulking phases, during which the body fat percentage is high and mass increases, and cutting phases, which aim to reduce body fat percentage while preserving muscle mass.
However, it is possible to do this within certain limits.
When blood glucose levels are high, insulin is released, and glucose is stored in muscle glycogen or liver glycogen – favorable conditions for gaining muscle mass.
When blood glucose levels are low, insulin secretion decreases, and fat becomes the primary source of fuel in the body – favorable conditions for weight loss.
Insulin levels act as a switch that can be controlled, toggling between “muscle mass gain” or “fat mass reduction” when necessary.
Every day, you need to plan in such a way that you can initiate the muscle mass gain process at the right time, and when necessary, fat burning.
If you want to gain mass – stimulate insulin secretion. This is especially important during training, before and after it.
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Insulin does not convert glucose into fat if it can first store it as glycogen. Glycogen stores are depleted during physical activity, so consuming carbohydrates during and after training will not lead to fat accumulation in the body.
Immediately after an intense strength training session, when glycogen stores in the muscles and liver are depleted, consume protein along with carbohydrates. They do not have to be sports-specific. This could be a gainer, whey protein with bread, or protein-rich food with porridge.
At other times of the day, limit the amount of carbohydrates in your diet to avoid gaining fat mass. Although small insulin boosts a few times a day can still be beneficial.
If your goal is to gain muscle mass and lose weight, then build your diet flexibly: stimulate insulin secretion during, before, and after training (by consuming fast carbohydrates) and suppress it at other times of the day by limiting carbohydrate intake.
