WHAT IS A KETOGENIC DIET

What the science says about ketogenic diets and why they probably won't help you "dry out" much.

The ketogenic diet

There are many different eating patterns, many of which even have pretty names, such as South Beach Diet, Weight Watchers Diet, Atkins Diet, HCG Diet, Volumetric Diet, paleo diet, IIFYM (literally “If It Fits Your Macros” - “if it fits into your KBJU”), reverse carbohydrate loading (carbs-backloading), the ketogenic diet, which will be discussed today.

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

Perhaps the most misunderstood aspect of the ketogenic diet is how it affects athletic performance and your ability to gain muscle and increase strength.

The ketogenic diet - from the word “ketosis”

Ketosis is a metabolic condition that occurs when the amount of carbohydrates in your diet is so low that the body simply has to use fatty acids and ketone body metabolism for energy. It seems that everything is simple, but let's understand this process to understand why our body goes into a state of ketosis.

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

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

A person needs an average of 1800 kcal per day (you can calculate your personal rate on a fitness calculator) in order to produce enough ATP and remain viable. At the same time, the midbrain requires about 400 kcal per day and uses almost only glucose as energy. This means that a personneeds to consume 100 g of glucose per day just to maintain normal brain function.

What does this have to do with ketosis? With a ketogenic diet, we remove almost all carbohydrates from our diet, which means we are depriving our brain of glucose. But we do need our brain to work somehow. Fortunately, the liver stores glucose in the form of glycogen and can donate a small amount of it to our brain to keep it working. Our liver can store 100-120 grams of glucose on average. With a critical lack of carbohydrates for the brain to function, the liver enables us to function normally throughout the day. In the end, however, the liver's glucose reserves cannot be replenished quickly, and carbohydrates are not only needed by the brain, which is why we have problems.

Our muscles are also a huge storehouse of glucose - they contain 400-500 grams of glucose in the form of glycogen stores.

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

In the absence of carbohydrates, the liver starts producing ketone bodies that are carried through the bloodstream to our brain and other tissues that do not use fat for energy.

Let's quickly go over 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 initiate the Krebs cycle.

During ketosis, our liver uses so much fat as energy that excess acetyl-CoA starts producing ketone bodies (beta-hydroxybutyrate, acetoacetic acid and acetone).

Gradually,with a regular deficiency of carbohydrates, the body reaches such a state that this process begins to occur constantly and the level of ketone bodies in the blood noticeably increases, then we can say that we are officially in a state of ketosis.

What is a ketogenic diet and how it differs from a “low carb” diet

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

What is the ketagen diet

The low-carb diet uses fats and carbohydrates for our daily energy needs. Our body does not store ketone bodies in the blood, and our tissues do not use ketones for energy.

With a ketogenic diet, our body reaches the point where ketone bodies are produced in large quantities and used as fuel. During such diet-induced ketosis, beta-hydroxybutyrate levels can be between 0. 5 and 3. 0 mM / L. You can even buy blood ketone test strips and measure your own.

A low-carb diet restricts the amount of carbohydrates in the diet (often just below 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 we discussed above, the ketogenic diet should be high in fat and low in carbohydrates.

On traditional and strict ketogenic diets, 70-75% of daily calories should be obtained from fat and only 5% from carbohydrates. The amount of carbs you can consume while staying in ketosis varies from person to person, but you can usually consume up to 12% of your calories from carbs and remain in ketosis.

Protein intake is also very important. Most of the exercisers have gotten into their heads that they must consume large amounts of protein, perhaps this is one of the factors of unsuccessful ketogenic diets.

As we discussed earlier,protein when consumed in high doses can be broken down to glucose (during gluconeogenesis) and thus you will not be able to enter ketosis.Basically, if you consume more than 1. 8 grams of protein per 1 kg of body weight, then this amount will be enough to get out of ketosis.

Ideally, in order to improve ketogenic status and maintain lean muscle mass, your diet should be approximately 75% fat, 5% carbohydrates, and 20% protein.

"Adaptation" phase on a ketogenic diet

If you read the ketosis literature, you will see one general trend. There is the most distinctive "adaptation" phase in which people experience a clouded state of mind, feel sluggish and lose energy. Basically, people feel very bad in the first weeks of a ketogenic diet. This is probably due to the lack of essential enzymes in our body, which are needed to efficiently oxidize certain elements.

In order to survive, our body tries to rewire itself to use other energy resources and learn to rely only on fat and ketone bodies. Usually, after 4-6 weeks of adaptation to the ketogenic diet, all these symptoms disappear.

Ketosis and Athletic Performance: A Review of Scientific Research

Let's take a look at a few studies that might answer this question.

Study # 1

The first study involved 12 people (7 men and 5 women, aged 24-60) who were on a self-prescribed ketogenic diet for an average of 38 days. The subjects performed moderate to intense training, their blood counts, body composition and maximum oxygen consumption were measured.

The study authors themselves conclude: “Radical carbohydrate reduction did not statistically significantly affect running performance, judging by the time the subjects began to fatigue and the level of maximum oxygen consumption, but the body mass composition improved, the participants lost 3. 4 kg of fatand gained 1. 3 kg of lean muscle mass. "

Thus, study participants lost weight, but showed no noticeable change in athletic performance. Also, the subjects decreased the body's ability to recover.

Study # 2

Another study involved 8 men of about 30 years old with at least 5 years of training experience. Subjects sat on a 4-week mixed + ketogenic cross-style diet and did extended stationary bike workouts at varying intensities.

The ketogenic diet also had a positive effect on body mass composition, as in the first study.

Interestingly, the relative values ​​of maximum oxygen consumption and oxygen consumption at the anaerobic threshold increased significantly on the ketogenic diet. The increase in maximum oxygen consumption can be explained by a decrease in body weight. However,maximum workload and workload at anaerobic threshold were lower after the ketogenic diet.

This means that theketogenic diet resulted in weight loss, but also a significant decrease in explosive strength and the ability to train at high intensity. Do you want to be stronger and train harder? Then don't think that the ketogenic diet is a good choice for this.

Study # 3

A third study examined how a 30-day ketogenic diet (4. 5% calories from carbohydrates) affects performance in the following exercises: hanging leg raises, floor push-ups, parallel bar push-ups, pull-ups, squat jumping, and 30-second jumps. The scientists also measured the body composition of the participants.

Here are the conclusions:

  1. The ketogenic diet caused a "spontaneous reduction in calorie intake" compared to the regular diet.
  2. No performance loss was found with the ketogenic diet exercise tested, however, no performance improvement was found.

As with other studies, there was a noticeable difference in body weight composition after the ketogenic diet: participants were able to lose weight. It should be borne in mind, however, that the participants selected for this study were already quite dry (about 7% body fat).

It's also important to mention that none of these tests looked at the glycolysis process as an energy source, they were more tests that tested explosive strength, phosphagenic system, and muscle fatigue tests.

Study # 4

In this study, 5 experienced cyclists performed the maximum oxygen consumption test and the time to exhaustion (TEE) test before and after a 4 week ketogenic diet.

Since this research is quite lengthy, I want to focus only on the performance aspect and muscle glycogen levels. The TEE test showed a huge difference between the participants. One subject improved TEE scores by 84 minutes in 4 weeks, the second showed an increase of 30 minutes, while two subjects dropped by 50 minutes altogether, and one subject remained unchanged:

Regarding muscle glycogen stores, a muscle biopsy showed thatglycogen stores after the ketogenic diet were almost half of their normal values ​​. This fact is already enough to assert that high performance can be said goodbye to.

Results of research on ketogenic diets

Let's take a look at what these 4 studies have in common:

  • Improved body composition.Each study resulted in a qualitative improvement in body composition. However, it is a controversial fact that this is the miraculous effect of the ketogenic diet, rather than spontaneous calorie restriction. Because if you take any research on any kind of diet and body composition, then any diet that restricts calories will improve body composition.

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

    It is likely that the ketogenic diet may still offer additional benefits in terms of body composition changes, but research has yet to show this.

    It should also be said that there is no literature to support the idea that a ketogenic diet can help build muscle. It only helps to lose weight.

  • Decreased performance at high intensity loads. The first two studies showed a decline in subjects' ability to exercise at high intensity. This is possible for two reasons: first, a decrease in intramuscular glycogen and second, a decrease in hepatic glycogen stores during high-intensity training.
  • Reduction of intramuscular glycogen stores. Decreased athletic performance during high-intensity training is a sign of decreased intramuscular glycogen levels, studies have shown. It can also negatively affect the recovery of the exercising athletes and the ability of the muscles to grow in size.

Mistakes People Make On Ketogenic Diets

While there is no clear benefit over conventional calorie restriction, ketogenic diets can be a good weight loss tool. If you are looking to lose weight (perhaps also through muscle mass), then maybe you should try it. Now let's look at the mistakes that people on a ketogenic diet often make so that you don't make them.

  1. Lack of adequate adaptation phase

    Switching to a ketogenic diet can be very difficult for some people. Very often, people quit the diet during the adaptation phase without completing it. The adaptation phase can last for several weeks, during which weakness is felt, consciousness is clouded, but after 2-3 weeks the energy levels return to normal.

    If you want to try a ketogenic diet, then allow plenty of time to adapt.

  2. Eating too much protein

    As we have already learned, too much protein can prevent ketosis. People often replace low carbohydrates with high protein on a ketogenic diet - this is a mistake.

  3. Using a ketogenic diet at high intensity exertion

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

    Since ketogenic diets reduce muscle glycogen levels, it is very difficult to train with high loads.

    Try a carbohydrate alternating diet instead of a ketogenic diet if you want to train at high intensity.

  4. Ketogenic diets prevent muscle gain

    Ketogenic diets can help you lose weight, but not gain muscle mass.

    CD will prevent you from training at high intensity and gaining lean muscle mass, so if these are the goals you are pursuing in your training, then it is better to give up the idea of ​​practicing CD.

Consuming both protein and carbohydrates together produces a greater anabolic effect than consuming these nutrients alone. On a ketogenic diet, you cut back on carbohydrates. And since you need both carbohydrates and protein for optimal muscle growth, you are missing one or both of these key nutrients.

Conclusion: ketogenic diets are neither optimal nor effective for building muscle and improving athletic performance. However, they can help you lose weight - just like any other calorie restriction below your personal daily value.