Anabolic (carbohydrate) window is a metabolic state in which the body has an acute need for nutrients (mainly proteins and carbohydrates), which, when consumed at a certain point in time, lead to a maximum anabolic response in the absence of fat tissue gain.
Many experts argue that it is the anabolic window and its timely filling that provide the greatest impetus for muscle growth. In addition, this window plays a more important role than all other meals.
Theoretically, taking protein-carbohydrate foods during the anabolic window in a certain ratio should lead to the launch of muscle fibers and replenishment of energy reserves according to the principle. However, many authors still recognize that the significance and even the presence of this window can vary depending on a number of factors. In addition, the significance and reliability of this information has not yet been subjected to scientific analysis. Moreover, some studies have completely refuted the classical ideas about the anabolic window in terms of the relationship between the time of nutrient intake and the development of anabolic processes.
Opinion of official science
Despite the logical and widespread opinion that immediate consumption of protein and carbohydrate food after training is very important for muscle growth, the scientific evidence for this is still rather weak. Most experiments and theoretical frameworks are based on the condition that training is performed on an empty stomach, accompanied by the breakdown of muscle protein (due to a negative amino acid balance), which persists after the end of training (regardless of the fact that exercise stimulates the synthesis of muscle tissue). It is clear that in this case, the action of the anabolic window can take place - wanting to urgently replenish energy and amino acid reserves, the body will begin to absorb everything that gets into it. Moreover, if the food is balanced in proteins and carbohydrates, then this meal will naturally lead to a positive amino acid balance with all the ensuing consequences (suppression, creation of conditions for new growth of muscle tissue). I don’t think anyone has any questions here.
However, in this regard, another question arises - how will eating before training affect the growth of muscle mass? According to research (Tipton KD, Rasmussen BB, Miller SL, Wolf SE, Owens-Stovall SK, Petrini BE, Wolfe RR: Timing of amino acid-carbohydrate ingestion alters anabolic response of muscle to resistance exercise. Am J Physiol Endocrinol Metab 2001, 281(2 ):E197-206), small doses of amino acids (6 grams) taken before exercise increase blood amino acid concentrations by approximately 130%, maintaining elevated levels for about 2 hours. A little later, research by the same author proved that taking 20 grams before starting a workout increases the concentration in the body up to 440%, maintaining it in this state for 3 hours.
Thus, based on the studies described above, we can conclude that there is no need to urgently take protein immediately after training, since by this time the level of amino acids in the athlete’s blood is still quite high. Therefore, food intake can be delayed by 1-2 hours without compromising muscle growth and recovery.
If you have to go to training after work or school (your last meal was 4-6 hours ago) and there is no opportunity to take a protein-carbohydrate meal or shake, to maintain anabolic processes in the body immediately after exercise, you need to eat or drink a protein shake. In this case, the anabolic effectiveness of the workout will be significantly higher than in the case of no nutrition immediately after the workout.
Correct conclusions
- To fully meet the needs of anabolic processes, it is necessary to take high-quality protein (whey, egg, beef). The size of one serving is 20-40 grams, each of which should be taken before and after training.
- The interval between pre-workout and post-workout meals should not exceed 3-4 hours.
- Taking into account the average workout duration of 45-90 minutes, the anabolic window lasts about 1.5 hours before the start and 1.5 hours after the end of the workout.
- The workout can be shifted closer to the pre-workout or post-workout meal, but with an interval of no more than 3-4 hours between them.
Post-workout nutrition
Everyone knows the recommendations of doctors - to eat after heavy physical exertion no earlier than 2 hours later. And these are not prejudices at all, just recommendations are given for ordinary people with their lifestyle and diet, and not for athletes, who not only have their own food intake, but also a different composition of foods.
Heavy, fatty food in the first hour after exercise will force the already tired body to spend more energy on processing, which can lead to digestive disorders and stomach pain.
Another thing is for athletes whose daily diet consists of carbohydrates, fiber and proteins in the form of drinks, supplements, vegetables and lean meats, such as chicken breast. Such food does not require significant processing costs. But it is not advisable to eat even such food within the first 30-40 minutes after completing a workout. The exception is special sports cocktails.
During heavy exercise or intense training, the body not only expends a huge amount of energy (carbohydrates), but also increases the level of adrenaline and cortisol, which, among other things, destroy protein tissue. This effect is also called the protein-carbohydrate window.
That is, this is the period after training when the body continues to expend energy. Its effect can last for a long period of time - from 30 to 120 minutes after training, depending on the characteristics of the metabolic process in the human body.
Let us also note the fact that there are a number of problems with the evidence base regarding the usefulness or harm of eating food during the protein-carbohydrate window, and the final conclusions have not been proven by research or have not been proven sufficiently to cast aside all doubts. Here is an example of research taken from the Journal of the International Society of Sports Nutrition:
| Researchers | Group of test subjects | Time to take sports nutrition | Control of the composition by a doctor | Completed studies | Type of training | results |
| Esmarck and others | 13 untrained older men | 10 g milk/soy protein consumed either immediately or 2 hours after exercise | Yes | MRI and muscle biopsy | Progressive strength training consisting of several sets of rows, leg presses and leg extensions, performed 3 days a week for 12 weeks | Significant increase in muscle cross-sectional area when using supplements |
| Cribb and Hayes | 23 young male bodybuilders | 1 g/kg supplement containing 40 g whey isolate, 43 g glucose and 7 g creatine monohydrate, consumed either immediately before or after exercise or in the early morning and late evening | Yes | Dual-energy X-ray absorptiometry and muscle biopsy | Progressive strength training consisting of exercises for major muscle groups, performed 3 days a week for 10 weeks | Significant increases in lean body mass and muscle cross-sectional area of type II fibers with supplementation |
| Willoughby and others | 19 untrained young men | 20 g protein or 20 g dextrose consumed 1 hour before and after exercise | No | Hydrostatic weighing, muscle biopsy, size measurement | Progressive strength training consisting of 3 sets of 6-8 repetitions for all major muscles, performed 4 days a week for 10 weeks | Significant increases in total body mass, fat-free mass, and thigh mass with protein and carbohydrate supplementation |
| Hulmi and others | 31 untrained young men | 15 g whey isolate or placebo consumed immediately before and after exercise | No | MRI and muscle biopsy | Progressive, periodized total body strength training consisting of 2-5 sets of 5-20 repetitions, performed 2 days per week for 21 weeks | Significant increase in cross-sectional area of the quadriceps, and in cases of placebo - increase only in the vastus lateralis muscles |
| Verdijk and others | 28 untrained older men | 10 g casein hydrolyzate or placebo consumed immediately before and after exercise | No | Dual-energy X-ray absorptiometry, computed tomography and muscle biopsy | Progressive strength training consisting of several sets of leg presses and leg extensions, performed 3 days a week for 12 weeks | |
| Hoffman and others | 33 young men in good physical shape | Supplement containing 42 g protein (milk/collagen blend) and 2 g carbohydrates consumed either immediately before or after exercise or in the early morning and late evening | Yes | Dual-energy X-ray absorptiometry | Progressive strength training consisting of 3-4 sets of 6-10 repetitions of several full-body exercises, performed 4 days a week for 10 weeks | No significant changes in body weight or muscle mass |
| Erskine and others | 33 untrained older men | 20 g of high quality protein or placebo consumed immediately before and after exercise | No | MRI | Workout consisting of 4-6 sets of elbow curls, performed 3 days a week for 12 weeks | No significant changes in muscle cross-sectional area |
Use for weight loss
This feature of the body is a definite plus for those who want to lose weight. At the same time, in sports literature you can find articles talking about the dangers of the “carbohydrate window”. The main argument in such articles is the destruction of protein tissues necessary for muscle growth.
But, if your goal is only to lose excess weight, then you shouldn’t worry about it. Just don’t forget and don’t be afraid to drink more water, preferably mineral water. This will not affect the process of losing excess weight, but it will compensate for the loss of fluid in the body and help you recover faster.
Drinking water is also very important because during training the heart works harder, but the loss of fluid leads to thickening of the blood, and after training, blood circulation slows down. And blood flow to the muscles is very important for their recovery, especially in the first hours after training. It is water enriched with minerals that will help improve blood circulation and speed up the recovery of the body.
Use for building muscle mass
It’s another matter if the goal of the workout is to increase muscle mass. There comes a time for every athlete when the stage of rapid muscle growth ends and for every millimeter in volume there are hours of hard work in the gym. Of course, such an athlete can be very frightened that after training his own body uses up what he spent several hours on the exercise equipment for.
It is important to quickly close this “carbohydrate window” to neutralize the unwanted effects of adrenaline and cortisol.
What is best to consume during this period?
First, let's look at the most common advice - drink protein and carbohydrate shakes. When consuming “fast carbohydrates,” insulin is produced, which blocks the action of adrenaline and cortisol. Shakes also often contain amino acids, a protein breakdown product, that is, what is necessary for muscle growth. But cocktails should be approached with caution, and not every body reacts the same way to a “pure” product.
Alternatives to cocktails can be:
- dairy products;
- nuts, fruits, honey;
It is believed that during the “carbohydrate-protein window” the body is able to better assimilate these foods and get more benefits from them, so eating during this period is useful.
It has been scientifically proven that using large amounts of protein can reduce the percentage of testosterone. The body is also forced to stop consuming excess protein from post-workout sports shakes, simply throwing it out in the urine. The optimal amount of protein to close the carbohydrate window is 0.4-0.5 g per kg of body.
The required minimum amount of carbohydrates after intense training is 0.15 g per kg of body weight. This amount of carbohydrates will ensure an increase in the percentage of insulin and interrupt the development of catabolic reactions. To quickly gain weight, you need to double your carbohydrate intake. After strength training, the athlete needs to take a large amount of appropriate carbohydrates, various cereals and vegetables in the amount of about 100-150 g. This replenishment will replenish the reserves of glycogen expended during training (complex carbohydrate, the main energy source in muscle work).
It should be especially noted that nutrients taken before exercise are much healthier than those taken after exercise. Energy exercises can increase the effectiveness of strength exercises, and, conversely, exercise with empty stomach syndrome is a waste of energy and time.
Accurate calculation and consumption of the required daily amount of calories (2500-2700 kcal for an athlete 70-75 kg) and a balanced selection of nutrients are much better for the growth of muscle tissue than a single consumption of an energy mixture after training.
To be completely objective, we will also consider the arguments against it, namely those that speak of exaggerating the negative impact of the “carbohydrate-protein window” on muscle growth.
Doesn't the protein-carbohydrate window exist?
In fact, proteins are not burned immediately after completing a workout, but after 20-30 minutes. The basis of training to increase muscle mass in general is damage to muscle tissue, which in turn provokes the body to increase and increase muscle volume in order to subsequently withstand such serious loads.
It’s not for nothing that they say that only 2-3 extreme repetitions in each approach, performed at the limit of strength, are useful. The process of recovery and such desired growth begins after the end of the workout, and takes quite a long time.
Now let’s compare two facts:
- The protein-carbohydrate window begins to act 20-30 minutes after training.
- The process of muscle tissue restoration begins some time after training and lasts a long time (up to several days).
In addition to the above, let’s consider the classic diet:
- Drink more fluids during training.
- Take a protein shake 30 minutes after your workout.
- Eat food 1-2 hours after training.
What conclusion can be drawn from this? Taking a protein shake coincides with the beginning of the “protein window” and reduces the negative impact on muscle growth. And eating food after 1-2 hours allows the body to work normally, without additional stress and negative effects on the digestive system.
In conclusion, we note that the classical diet is justified by years of positive results, and there is still insufficient information about the benefits of intensive food intake during the “carbohydrate-protein window”.
Personal trainer, pharmacologist, nutritionist
Draws up and conducts personal training programs for body correction. Specializes in sports traumatology and physiotherapy. Conducts classical medical and sports massage sessions. Other authors
Many people wonder what foods to eat after a workout. Detailed information about nutrition after exercise, or what it means to “close the protein-carbohydrate window.”
Surely you have identified people in the gyms who, after training drink protein shakes, eat bananas, and some even carry with them a container with buckwheat, for example, and boiled chicken. From the outside it looks quite wild, but people who strictly monitor the quality of their body, concerned about muscle growth and the fat burning process, do this because they know about the existence of the so-called protein-carbohydrate window.
Before you figure out what this window is, you need to define two concepts - anabolism and catabolism.
Anabolism and catabolism
Anabolism is a set of chemical processes aimed at creating new cells and tissues. To put it exaggeratedly, these are the processes of muscle tissue growth. The process absolutely opposite to anabolism is catabolism. Catabolism is the process of metabolic breakdown into simpler substances to release energy. For an athlete, what plays a role in the first place is how exactly this energy is generated. We are interested in the catabolism (breakdown) of proteins, or more precisely, how to prevent this, because in this case, our muscles will be used as an energy source (I wrote in detail about the formation of energy in the article “When is the best time to do cardio?”).
What is the protein-carbohydrate window?
Protein-carbohydrate window- This is the period of time after training when the body is in dire need of replenishment of nutrients and is capable of maximum anabolic response. They often simply say “carbohydrate” window or “protein” window. There is a lot of debate as to how long this “window” lasts. On average they talk about 1-2 hours after training. It is believed that this window opens approximately half an hour after the end of the training.
There is also an expression “close the carbohydrate window”, which implies the consumption of certain foods that reduce catabolism processes and trigger anabolism.
How to close the carbohydrate window when gaining weight?
If your goal is to gain muscle mass, then you must replenish your reserves of both protein and carbohydrates. This is exactly the case when the combination of porridge and boiled chicken or fish works great. Bananas and grapes are good in this case. In order to stop catabolism processes- You need to raise the level of insulin in the blood. Sweets are often used for this. Marshmallows are ideal - they are pure carbohydrates.
Gainers - protein shakes with a high carbohydrate content - have been developed specifically for weight gain.
How to close the carbohydrate window when burning fat?
There is an opinion that to burn fat after a workout you don’t need to eat at all. This opinion is based on the fact that having exhausted all reserves, energy will be drawn from fat. Actually this is not true.
If you finished a workout with a long cardio load and actually used fat as energy during the workout, then muscle breakdown will still begin at the end of the workout. Even if you do not set a goal to increase muscle mass, then losing the muscles that you have is, at a minimum, stupid. Therefore, your task is to consume protein. The most convenient option is protein isolate, i.e. protein shake with minimal fat and carbohydrates. Or it could be any low-fat dairy product.
And to receive more useful information every day, subscribe to ours.
Anyone who has ever tried to learn the basics of proper nutrition has come across the popular belief that after an intense workout, the so-called protein-carbohydrate window opens.
And indeed, all popular fitness magazines, books, and Internet portals promote the same theory, which says: “In the next 20 to 30 minutes after training, you need to eat food rich in protein and carbohydrates. This is the only time when carbohydrates with a relatively high glycemic index, that is, fast carbohydrates, are allowed to be included in the diet. During this period of time, the so-called post-workout, anabolic or protein-carbohydrate window is open in the body. For this reason, post-workout nutrition is necessary mainly for muscle recovery and activation of muscle growth, since almost all nutrients are included in anabolic processes.”
In fact, everything happens a little differently, and if we consider this issue from a scientific point of view, it becomes clear that these are nothing more than facts taken out of context and they contradict human physiology.
After training, recovery processes really begin in the body. After the working state of the body is called the recovery period, a distinction is made between urgent (early period) and delayed recovery (late period).
Urgent recovery is the process of eliminating metabolic products accumulated in tissues (metabolites) during exercise and eliminating the resulting oxygen debt. It occurs immediately after the end of each exercise and continues for 30-90 minutes after completing the training work.
Delayed recovery is a return to the original level of the body’s energy resources, enhancing the synthesis of structural proteins and enzymes. It extends to many hours of rest after work.
During the period of delayed recovery, glycogen reserves accumulate in the muscles and liver; these restoration processes occur within 12 - 48 hours. What is the source of glycogen synthesis? First of all, lactic acid enters the blood. It enters the liver cells, where glucose synthesis first occurs, and glucose is the direct building material for glycogen synthetase, which catalyzes glycogen synthesis.
If glycogen consumption in the muscles was very high and it needs to be synthesized in large quantities, the glycogen content in the liver at the beginning of rest may even decrease slightly due to the increased supply of glucose to the muscles. For the resynthesis of glycogen in muscles, only internal substrate funds are not enough; additional amounts of carbohydrates must be supplied with food.
That is, in simple words - after training, you must definitely consume carbohydrates for recovery, but not in the next 30-60 minutes, but within 12-48 hours. That is, you don’t need to worry so much about eating after a workout.
If you can’t eat right after a workout, that’s okay. The total amount of carbohydrates consumed per day is of primary importance for the body!
After the resynthesis of the body's energy reserves, the processes of resynthesis of phospholipids and proteins are significantly enhanced, especially after heavy strength work, which is accompanied by their significant breakdown. Restoration of the level of structural and enzymatic proteins occurs within 12 - 72 hours.
That is, there is no urgent need to consume large amounts of protein immediately after training. Until the body restores glycogen reserves, protein synthesis will not begin. Again, the total amount of protein consumed per day is much more important.
This is what the situation looks like from a physiological point of view, so stop believing popular fitness magazines, books, diet forums and would-be trainers repeating the same myth. Read biochemistry and physiology textbooks, and trust only scientific facts!
Conclusion:>
There is no protein-carbohydrate window! Or rather, it is there, but it is wide open for 12-72 hours after training.
There is no need to sit down at the table immediately after training; there is no need to be afraid of catabolic processes and muscle breakdown. Your main task is to accurately count the total amount of nutrients you eat throughout the day. That is, you need to know exactly how many proteins, fats and carbohydrates you consume per day.
The carbohydrate window is a conditional period after the end of strength training, during which the athlete’s muscles are most sensitive to the absorption of nutrients (primarily proteins and fast carbohydrates). It is believed that the energy from food consumed during the carbohydrate window is spent primarily on muscle recovery and growth, and not at all on gaining fat mass.
Research suggests that the carbohydrate window ranges from 30-45 minutes after low-intensity strength training to 2-4 hours after an active circuit or HIIT workout¹. In addition, consuming fast carbohydrates immediately before the start of physical training is also beneficial for muscle growth and is included in the concept of the carbohydrate window².
To close the carbohydrate window after strength training, you need about 15-25 g and 10-12 g. This will help lower cortisol levels, stop the process of muscle breakdown and start the process of muscle growth. The maximum amount of fast carbohydrates after training, guaranteeing an increase in body weight without excessive fat growth, is 30-40 g.
Gainer: a source of fast carbohydrates
Gainer is a sports nutrition that is a mixture of whey protein, fast carbohydrates and vitamins. Consuming such a cocktail to close the carbohydrate window causes an increase in body weight - however, both muscle and fat reserves grow. That is why it is recommended only for ectomorphs who are prone to thinness and have problems with muscle growth.
When training for muscle definition (that is, for cutting) or during any training for fat burning, a gainer is categorically not recommended. In most cases, to stop catabolic processes, a portion of whey protein and a sufficiently small amount of simple carbohydrates (about 10 g) in the form of a sports isotonic drink, a small piece of fruit or 100 ml of juice are enough.
Immediately after the end of strength training, the level of glucose (and insulin) in the athlete’s blood is minimal - the body is in a “spending” mode, and not in a “gaining” mode. Eating fast carbohydrates is the fastest way to stop the catabolic processes of muscle breakdown (i.e., reduce the level of the hormone cortisol³) and switch to energy reserve mode (i.e., increase insulin).
Note that the body needs fast carbohydrates - otherwise the absorption of nutrients will take several hours, negating all the benefits of the carbohydrate window. At the same time, consuming fast carbohydrates often plays a much more important role in accelerating muscle growth processes than taking whey protein.
How many carbohydrates do you need?
The minimum dose of carbohydrate intake to close the carbohydrate window is 0.15 g per kg of body weight (3) - that is, approximately 10-12 g for an athlete weighing 75 kg. This amount of carbohydrates is enough to stop catabolic processes and increase insulin levels. If your goal is to gain weight as quickly as possible, increase carbohydrates to 30-40 g.
It is also important that the meal following strength training should include a lot of the right carbohydrates, vegetables and various cereals - a total of at least 100-150 g of carbohydrates. This is extremely important for replenishing the reserves spent during training (that is, carbohydrates stored in the muscles and being the main source of energy for their work).
Proteins after strength training
Although it is traditionally believed that the more protein an athlete consumes, the faster his muscles grow, this opinion is refuted by the latest scientific research. Scientists say that excessive consumption of sports protein not only reduces the percentage and speed of its absorption, but can even lead to a drop in testosterone levels (due to a lack of fat in the diet).
To close the carbohydrate window after strength training, an athlete needs about 15-25 g of whey protein, which completely covers the energy needs of the muscles for recovery¹. However, a much more important role for muscle growth is played by the total protein intake during the day - but even in this case, only enough for each kg of dry body weight.
Amino acids BCAA
Another secret to increasing the effectiveness of strength training (especially when performing) is taking the essential amino acids BCAA. In most cases, we are talking about a dosage of 3-5 g for every 30 minutes of intense exercise. Amino acids dissolve in water and are consumed directly during training.
The reason for use is that they stop various catabolic processes in the body, reduce the feeling of fatigue and ultimately improve strength performance. In addition, creatine is an important supplement for accelerating muscle growth - add about 3-5 g of creatine to a protein shake and consume it immediately after finishing your workout.
Carbohydrate window: truth or myth?
The reason why the carbohydrate window is only a “conditional” period is the lack of clear recommendations about its duration. Modern research suggests that the carbohydrate window does not last 30-45 minutes after training, as was previously thought, but at least 2-4 hours. In this case, the period of active absorption of nutrients by the body can last more than a day.
It also plays a role that sufficient consumption of proteins and carbohydrates before strength training (including) is often much more important than the consumption of these same nutrients after training. In other words, if you come to the gym hungry, it will minimize the effects of strength training - regardless of whether you subsequently close the carbohydrate window according to the rules or not.
***
To close the carbohydrate window after strength training, you need about 15-25 g of whey protein and 10-12 g of fast carbohydrates. This will help lower cortisol levels, stop the process of muscle breakdown and start the process of muscle growth. The maximum amount of fast carbohydrates after training, guaranteeing an increase in body weight without excessive fat growth, is 30-40 g.
Scientific sources:
- Cortisol and physical exercise,
- Nutrient timing revisited: is there a post-exercise anabolic window?,
- Coingestion of carbohydrates with protein does not further augment postexercise muscle protein synthesis,
