What is a ketogenic diet?

What the science of ketogenic diets says and why they don't help you "dry out" much.

There are different types of food, many of which have beautiful names, such as South Beach Diet, Weight Watchers Diet, Atkins Diet, HCG Diet, Volumetric Diet, Paleo Diet, IIFYM (literallyif it fits your macro ”-“ if it fits your KBJU ”), carbohydrate reverse (carbohydrate reload), ketogenic diet, will be discussed today.

One of the most commonly used diets is ketogenic. Although many people use it to burn fat, this diet is surrounded by a lot of misinformation.

The most misconception about a ketogenic diet is how it affects athletic performance and muscle mass gain and strength.

Ketogenic diet - from the word "ketosis"

Ketosis is a metabolic condition in which the amount of carbohydrates in a food is too low, forcing the body's metabolism of fatty acids and ketone bodies to use energy. Everything seems simple, but let's understand this process in order to understand why our body is in a state of ketosis.

Our bodies need enough energy in the form of ATP to function.

ATP is a universal energy source for all biochemical processes in living systems.

A person needs an average of 1, 800 kcal per day (calculated from a fitness calculator) to develop enough ATP and maintain vitality. At the same time, the midbrain requires about 400 kcal per day and uses almost exclusively glucose as energy. Therefore, a personneeds to consume 100 g of glucose per day to ensure the normal functioning of the brain.

What does this have to do with ketosis? With a ketogenic diet, we eliminate almost all carbohydrates from the diet, thus depriving our brain of glucose. But we need our brains to work in some way. Fortunately, the liver stores glucose in the form of glycogen and is able to supply some of it to the brain to keep it functioning. Our liver can store an average of 100-120 grams of glucose. Because the brain does not have enough carbohydrates to function, the liver is able to function normally throughout the day. But in the end, the liver’s glucose reserves can’t be restored quickly, and carbohydrates aren’t just needed by the brain, so we have problems.

Our muscles are the largest store of glucose - they contain 400-500 grams of glucose in the form of glycogen stores.

However, glycogen stores are not primarily designed to nourish the brain. Unfortunately, due to the lack of an enzyme that breaks down glycogen (glucose-6-phosphate dehydrogenase) in our muscles, our muscles cannot break down glycogen and feed our brains.

In the absence of carbohydrates, the liver begins to produce ketone bodies, which pass through the blood to the brain and other tissues that do not use fat for energy.

Let's take a quick look at the biochemistry of these processes. When you "burn fat, " the fatty acid molecules in your body are converted to acetyl-CoA, which in turn combines with oxaloacetate to start the Krebs cycle.

As our liver uses a lot of energy during ketosis, excess acetyl-CoA begins to produce ketone bodies (beta-hydroxybutyrate, acetoacetic acid, and acetone).

Gradually,with a persistent deficiency of carbohydrates, the body reaches such a state that this process begins to be continuous and the level of ketone bodies in the blood rises significantly, so we can officially say that we are in a state of ketosis.

What is a ketogenic diet and how is it different from a "low carb" diet?

A low-carb diet and a ketogenic diet are not the same thing.

Low carb diets use fat and carbohydrates for our daily energy needs. Our bodies do not store ketone bodies in the blood, and our tissues do not use energy as ketones.

With a ketogenic diet, our bodies produce large amounts of ketone bodies and reach the point where they can be used as fuel. During ketosis caused by such a diet, beta-hydroxybutyrate levels may be between 0, 5 and 3. 0 mm / l. You can even buy blood ketone test strips and measure them yourself.

A low-carbohydrate diet limits the amount of carbohydrates in the diet (usually less than 100 grams per day), but beta-hydroxybutyrate levels do not reach 0, 5 and 3. 0 mm / l.

How to eat on a ketogenic diet

As discussed above, a ketogenic diet should be high in fat and low in carbohydrates.

In traditional and strictly ketogenic diets, 70-75% of daily calories should come from fat and only 5% from carbohydrates. The amount of carbohydrates you consume during ketosis varies from person to person, but you can usually eat up to 12% of your carbohydrate calories and stay in ketosis.

Protein intake is also very important. Most exercisers have begun to think that they need to drink more protein, which is probably one of the factors in unsuccessful ketogenic diets.

As discussed above,protein can break down into glucose (during gluconeogenesis) when used in high doses, so you can't get into ketosis.In general, if you consume more than 1. 8 grams of protein per kilogram of body weight, this amount is enough to get rid of ketosis.

To improve ketogenic status and maintain lean muscle mass, your diet should be about 75% fat, 5% carbohydrates and 20% protein.

"Adaptation" phase on ketogenic diet

If you read the ketosis literature, you can see a general trend. People have a very special "adaptation" phase, when they are exposed to a clouded mind, feel slow and lose their strength. In general, people feel unwell in the first weeks of a ketogenic diet. This is probably due to a lack of enzymes needed to effectively oxidize certain elements.

In order to survive, our body uses other energy resources and tries to learn to rely on fat and ketone bodies again. Typically, all of these symptoms disappear after 4-6 weeks of adaptation to a ketogenic diet.

Ketosis and Sports Indicators: A Review of Scientific Research

Consider a few studies that answer this question.

окуу1 reading

The first study included 12 people (7 men and 5 women aged 24-60 years) on an average of 38 days of ketogenic diet. Subjects underwent moderate to severe exercise, and their blood counts, body composition, and maximum oxygen consumption were measured.

The authors of the study concluded: “The radical reduction in carbohydrates did not have a statistically significant effect on circulatory function, as subjects began to lose weight and had higher oxygen consumption than the maximum oxygen consumption, participants lost 3 kg of fat, 3 kg of fat, and 3 kg of fat. increased muscle mass. "

Thus, study participants lost weight, but there was no significant change in athletic performance. Subjects also reduced the body's ability to regenerate.

окуу2 readings

Another study involved 8 men, approximately 30 years old, with at least 5 years of experience. Subjects sat on a 4-week mixed + ketogenic cross-style diet and trained for a long time on a regular bike of varying intensity.

As in the first study, the ketogenic diet had a positive effect on body composition.

Interestingly, the relative importance of maximal oxygen consumption in the ketogenic diet and oxygen consumption at the anaerobic threshold has increased significantly. The increase in maximum oxygen consumption is explained by a decrease in body weight. However,maximum workload and anaerobic threshold workload were lower after a ketogenic diet.

Consequently, theketogenic diet led to weight loss, but the explosive power was significantly reduced and the ability to exercise at high intensity. Do you want to be stronger and train more? Then don't think that a ketogenic diet is a good solution for this.

№3 readings

The third study looked at how a 30-day ketogenic diet (4. 5% of carbohydrates) works in the following exercises: lifting a leg, lifting the floor, pushing on the floorpole vault, stand-up, high jump and 30-second jump. The researchers also measured the participants' body composition.

Results:

1. The ketogenic diet caused a "spontaneous reduction of calories" compared to a normal diet.
2. No loss of effectiveness was found with ketogenic diet exercise, but no improvement in performance was found.

As with other studies, there were significant differences in body composition after the ketogenic diet: participants were able to lose weight. It should be noted that participants selected for this study were already dry (approximately 7% body fat).

It is also important to note that none of these tests considered the glycolysis process as a source of energy, but rather more tests that tested explosive power, the phosphagen system, and muscle fatigue.

№4 readings

In this study, 5 experienced cyclists were tested for maximum oxygen consumption and fatigue time (TEE) before and after a 4-week ketogenic diet.

Since this study is so long, I would like to focus only on the performance aspect and muscle glycogen levels. The TEE test showed a big difference between the participants. One lesson improved TEE scores by 84 minutes in 4 weeks, another by 30 minutes, and two subjects decreased by a total of 50 minutes, leaving one subject unchanged:

Regarding muscle glycogen stores, a muscle biopsyshowed that glycogen stores following a ketogenic diet were almost half of their normal values ​​. Suffice it to say that this fact can be said goodbye to high figures.

Results of research on ketogenic diets

Let's look at the generality of these 4 studies:

• Improved body composition.Each study led to a qualitative improvement in body composition. However, it is a debatable fact that this is not a spontaneous calorie restriction, but a miraculous effect of a ketogenic diet. This is because if you do any research on different diets and body composition, any diet that restricts calories will improve the body's composition.

  In the third study, subjects consumed an average of 10, 000 kcal (minus 333 kcal per day) in 30 days than a normal diet, and of course, they lost weight.

  Ketogenic diets can still provide additional benefits in terms of changes in body composition, but studies have not shown this.

  There is no literature to support the idea that a ketogenic diet helps build muscle. It only helps to lose weight.

• Deteriorated in high-intensity training. The first two studies showed a decrease in the ability of subjects to exercise at high intensity. This is possible for two reasons: first, a decrease in muscle glycogen, and second, a decrease in the liver's glycogen stores during high-intensity exercise.
• Decreased glycogen stores in muscle. Studies show that a decrease in athletic performance during high-intensity exercise is a sign of a decrease in muscle glycogen levels. It can also negatively affect the recovery and muscle mass of athletes who exercise.

Mistakes made by people on ketogenic diets

While there is no benefit to normal calorie restriction, ketogenic diets can be an excellent tool for weight loss. If you want to lose weight (probably through muscle mass), then you should give it a try. Now let’s look at the mistakes that people on a ketogenic diet make so often that you don’t.

1. Lack of a suitable adaptation phase

   Switching to a ketogenic diet can be very difficult for some people. In most cases, people leave the diet without completing the adaptation phase. The adaptation phase can last for several weeks, during which there is a feeling of weakness and loss of consciousness, but after 2-3 weeks the energy level is restored.

   If you want to try a ketogenic diet, take a long time to adapt.

2. Eating Excess Protein

   As we already know, too much protein prevents ketosis. It is a mistake for people to replace the most common carbohydrates in a ketogenic diet with high protein.

3. Using a ketogenic diet for high-intensity exercise

   When performing high-intensity anaerobic exercise, our body relies primarily on blood glucose stores, liver and muscle glycogen, and gluconeogenesis.

   Because a ketogenic diet lowers muscle glycogen levels, it is very difficult to exercise at high loads.

   Try a carbohydrate replacement diet instead of a ketogenic diet if you want to exercise at a high level.

4. Ketogenic diet prevents muscle growth

   Ketogenic diets help you lose weight, but do not increase muscle mass.

   CDs prevent you from training at a high intensity and increasing lean muscle mass, so if you are pursuing these goals in your workout, it is best to abandon the idea of ​​exercising with a CD.

Combining both protein and carbohydrates has a greater anabolic effect than eating these foods alone. In a ketogenic diet, you can reduce carbohydrates. You also need one or two of these essential nutrients, as you also need carbohydrates and proteins for optimal muscle growth.

Conclusion: Ketogenic diets are neither optimal nor effective for increasing muscle mass and improving athletic performance. However, they do help you lose weight - like any restrictions on individual calendar calories.