Basic metabolism. Basal Metabolism: How to Calculate Metabolic Rate

Basal metabolism, or, as it is also called, basal metabolism, is the number of calories that the body needs to sustain life: the ability to breathe, provide blood flow, and other equally important processes. These calories will be burned even if you lay motionless on the couch all day.

Knowing about the features of basal metabolism is important for everyone who monitors health. But there are people who absolutely need this information: these are those who plan to sit down on a tough one and drastically limit the calorie content of their food.

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If you overdo it and do not provide the minimum required calories, the body will be forced to slow down the metabolism. But this will not help to lose weight, because muscle mass will decrease, and not excess fat. Yes, and such experiments will not affect health in the best way.

What does basal metabolism depend on?

1. Gender
Men have a higher basal metabolic rate because men tend to have more muscle mass than women.

2. Age
The younger a person is, the higher his basal metabolic rate. With age, the metabolic rate gradually slows down.

3. Height and weight
The taller the person and the larger he is, the more heat his body gives off to the environment. Accordingly, the basal metabolic rate of such a person is higher.

4. Body structure
The more muscle and less fat a person has, the more energy he needs.

5. Physical activity
The more a person moves and plays sports, the faster fat is burned and muscle mass increases. As a result, the basal metabolism is accelerated.

6. Nutrition
A sharp decrease in calories consumed slows down the metabolism.

7. The state of the endocrine system
The less hormones produced by the thyroid gland, the pituitary gland and the gonads, the more the basal metabolism decreases.

8. Individual features
All people require different amounts of energy to digest and assimilate food.

9. Body temperature
With an increase in body temperature, the energy costs of the body increase.

10. Climatic conditions
In the middle lane and in the north, people's metabolism is much faster (by 10–20%) than, for example, in the tropics.

Basic metabolism is an individual thing, but if there are no serious health problems, you can calculate it, albeit with a small error, using special formulas.

Formulas for calculating basal metabolism

1. Harris-Benedict Formula

For men: 66.5 + (13.75 × weight (kg)) + (5.003 × height (cm)) - (6.775 × age)
For women: 655.1 + (9.563 × weight in kg)) + (1.85 × height in cm)) - (4.676 × age)

2. Muffin-Jeor formula:

For men: 9.99 x weight (kg) + 6.25 x height (cm) - 4.92 x age + 5
For women: 9.99 x weight (kg) + 6.25 x height (cm) - 4.92 x age - 161

You can use any of these formulas or both at once. The results will be similar: plus or minus 50-100 calories.

3. Ketch-McArdle formula

This formula is considered the most accurate, as it takes into account the structure of the body. To use it, you need to know your body fat percentage. Find out the fat content in the body help in fitness centers.

To calculate your basal metabolic rate, you first need to know your fat-free body mass. With a weight of 55 kg and a total fat content of 20 percent, this figure will be 44 (55-55 * 0.2). Then the result obtained must be multiplied by 21.6 and added to the resulting number 370.

OO = 370 + (21.6 * fat-free mass).

Decided to go on a strict diet? Remember: the calorie content of foods eaten during the day should in no case be lower than the basal metabolic rate. Over time, getting rid of extra pounds, you can gradually reduce the calorie content of food without harming your health and figure.

How to Calculate Total Calorie Expenditure

To find out how many calories you spend during the day, you need to multiply the basal metabolic rate by the coefficient of physical activity.

Physical activity coefficients

• Sedentary lifestyle: coefficient 1.2.
• Training less than three times a week: coefficient 1.375
• Training up to five times a week: coefficient 1.55
• Training 6-7 times a week: coefficient 1.725
• Heavy physical labor: coefficient 1.9.

If you do not want to calculate your calorie consumption manually, use the calorie calculator.

How to use the information received

In order to always be in good shape, it is enough to adhere to the daily calorie intake, calculated taking into account the basic exchange and the level of your activity.

In order to, it is important to create a reasonable calorie deficit. This can be achieved by reducing the calorie content of food or by increasing the time and intensity of training.

For, again, reasonably increase the number of calories eaten. Remember: even the most healthy foods can be high-calorie.

We all know the main principle of achieving progress in sports. 40% training, 20% sleep, and 40% nutrition. But, how to properly calculate nutrition to achieve certain goals? Of course, a plan is drawn up for this, which takes into account the physical and mental needs and costs. But one single factor falls out of this whole formula, which will be considered in the following material - the main metabolism.

What it is?

Basal metabolism is the expenditure of energy for the basic needs of the body. They include:

• Synthesis of major hormones.
• Synthesis of basic enzymes.
• Ensuring basic cognitive function.
• Digestion of food.
• Maintaining immune function.
• Maintaining the ratio in relation to catabolic.
• Maintenance of respiratory functions.
• Transportation of the main energy elements by blood.
• Maintaining a constant body temperature according to Rubner's law.

And this is not a complete list of what is happening in our body. In particular, even when a person is sleeping, most of the processes, albeit in a slower manner, help synthesize new building blocks and break down glycogen into glucose. All this requires a constant influx of calories that a person receives from food. In particular, this basic consumption is the daily minimum norm of how many calories you need to maintain the basic functions of the body.

Rubner surface

Oddly enough, but sometimes the metabolism is determined not only by biochemical processes, but also by simple physical laws. In particular, the scientist Rubner found a relationship that links the total surface area with the amount of calories burned. How does it really work? There are 2 main factors that made his crazy guess right.

• 1st - the size of the body. The larger the surface of the body, the larger the organs, and the greater the leverage in any action, which sets in motion a larger "machine" that consumes "more fuel".
• 2nd - keeping warm. For the normal functioning of the body, metabolic processes occur with the release of heat. In particular, for a person it is 36.6. Moreover, the temperature (with rare exceptions) is evenly distributed throughout the body. So, to heat a large area, you need more energy. All this is related to thermodynamics.

Therefore, from all this we can conclude:

Thick people do expend more energy during their basal metabolic rate. Tall people are most often thin due to a caloric deficit caused by an increased basal metabolic rate and the expense of keeping warm for more body area.

If we consider the level of basal metabolism as a dynamic system, mobile, then there are factors that determine the basic background, and the amount of energy distributed:

• The amount of incoming energy. The more frivolously a person relates to his diet (a constant excess of calories, frequent snacks,), the more actively the body spends them even in a passive mode. All this leads to a constant hormonal background and a general increase in the load on the body, and, as a result, a faster failure of individual systems.
• The presence of artificial stimulants of metabolic rate. For example, people who use caffeine have a lower basal metabolic rate when they cut out caffeine. At the same time, their hormonal system begins to malfunction.
• General human mobility. So, during sleep, the body transports glucose from the liver to the muscles, synthesizes new amino acid chains, and synthesizes enzymes. The amount (and, therefore, resources) that are spent on these processes directly depend on the total load on the body.
• Change in basal metabolic rate. If a person has taken himself out of balance (natural speed), then the body will spend additional energy on restoring and stabilizing all processes. And this applies to both acceleration and deceleration.
• The presence of external factors. A change in temperature will force the skin to generate more heat to maintain the overall temperature, which can change the dynamic factor that affects the overall level of basal metabolic rate.
• The ratio of absorbed and excreted nutrients. With a constant surplus of calories, the body can simply refuse excess nutrients, in this case, basal waste will increase by the process of converting useful nutrients into transportation slag.

In addition, it is worth highlighting the main end products of metabolism, which are excreted from the body, regardless of its speed.



What is regulated?

Now we need to determine not only what the main energy is spent on during the general metabolism, but also how the amount of energy expended is regulated.

• First, it is the initial metabolic rate, which is defined as the ratio of total mobility to the presence of excess energy.
• Secondly, basal metabolism is regulated by the initial level of hormones in the blood. For example, for diabetics, or for people suffering from gastrointestinal problems - the overall metabolism will differ in speed and, accordingly, in costs from the average.
• Third, age. Oddly enough, however, with age, basal metabolism slows down, this is due to the optimization of the body's resources, in an attempt to extend the life of the main systems for a longer time.
• An abundance of oxygen. Oddly enough, but without the oxidation of complex polysaccharides to the level of simple monosaccharides, energy release is impossible. More precisely, the mechanism of its isolation changes. With a large amount of oxygen, the rate of excretion increases, which increases the cost of basic metabolism. At the same time, in conditions of lack of oxygen, the body can switch to the heating of fatty tissues, which is radically different in speed and cost.

Continuing to draw analogies with machines. This is a reduction in speed in order to reduce the oil consumption in the engine, and, accordingly, reduce the overall wear of the engine, thereby extending the life of the individual part.

imbalance

The calculation of the basic metabolism takes into account dynamic stresses. So, for example, playing sports takes the body out of balance, forcing it to gradually speed up the metabolism, and completely rebuild itself under new conditions. This, in turn, causes resistance (which is characterized by a large loss of nutritional potential, and, possibly, for some time, the removal of most body systems from normal mode).

In addition, to regulate the effects of stress, the costs of maintaining the emotional background increase. Well, plus, if the balance is finally brought out, the body begins to completely rebuild itself under the new regime with a new metabolic rate. So, for example, a sudden change in diet, followed by a slowdown in metabolism, is also a sufficient factor to change the level of basic consumption. When the system is out of balance, it will tend to it. This determines the current level of enzymes and hormones.



Formulas for calculating basic needs

The formula for calculating the basic metabolism is imperfect. It does not take into account factors such as:

• Individual metabolic rate.
• The ratio of subcutaneous and deep fat.
• Presence of glycogen storage.
• Outside temperature.

However, for a general estimate, such a formula is also suitable. Before the table, we insert explanations:

• MT - body weight. For the most accurate calculation, it is better to use a net mass (excluding adipose tissue).
• R - growth. The formula is used because of Rubner's theorem. It is one of the most inaccurate coefficients.
• The free coefficient is a magic figure that adjusts your result to the norm, proving once again that without such a coefficient (individual for each case), it will not be possible to obtain an adequate calculation of basal metabolism.

Floor	Age	The equation
M	10-18	16.6 mt + 119R + 572
AND	10-18	7.4 mt + 482R + 217
M	18-30	15.4 mt + 27R + 717
AND	18-30	13.3 mt + 334R + 35
M	30-60	11.3 mt + 16R + 901
AND	30-60	8.7mt + 25R + 865
M	>60	8.8 mt + 1128R - 1071
AND	>60	9.2 mt + 637R - 302

It is important to understand that the calculation formula does not take into account the uneven consumption of calories throughout the day. So, for example, during the day during a meal or after a workout, an accelerated metabolism causes the body to consume more energy, even if it does not use it so rationally. While in sleep, metabolic processes are optimized as much as possible, which allows you to achieve the optimal result for your goals.

General metabolism

Naturally, the main stages and processes occurring in the body during the main metabolism are not the only expenses. When creating a nutrition plan, say, for weight loss, you need to perceive basal metabolism not as a constant (calculated according to the formula), but as a dynamic system, any change in which leads to a change in the calculations.

First, in order to consume the full calorie content of food, you need to include in the list of calorie waste for all actions performed.

Note: The calculation of the motor and mental needs of a person was considered in more detail in the article "".

Secondly, a change in the metabolic rate that occurs just in the course of physical activity, or its absence. In particular, the appearance of a protein and carbohydrate window after training stimulates not only the acceleration of metabolism, but also a change in the body's expenditure on digestion. At this time, basal metabolism increases by 15-20%, albeit in the short term, not counting other needs.

Outcome

The calculation of basal metabolism for an athlete, of course, is not a necessary and determining factor for achieving optimal growth. The imperfection of the formulas, the change in constant processes, requires regular correction. However, when initially calculating calorie expenditure to create a surplus or deficit, basal metabolism will help you understand how to adjust the resulting numbers.

This is especially important for those who are accustomed not to draw up a meal plan on their own, but to use ready-made diets. We all understand the principles of losing weight, and, therefore, any diet needs to be adjusted to suit ourselves. And, that for a 90-pound fat man, losing weight, for a 50-pound phyton, can be harmful and excessive.

BX– what does this term mean? Probably, something is being exchanged, and there are other exchanges besides the main one? Yes, dear reader, you are on the right track. Your basal metabolic rate is the number of calories your body burns to keep your body alive. In simple terms, the body burns calories for the body's work (breathing, metabolism), even without physical exertion. This exchange accounts for up to 75 percent of the calories consumed by our body. Of course, each person is unique, which means that each person will have their own basal metabolic rate.

Rubner's surface law and, where does the main exchange

This is a law derived by the German physiologist and hygienist Max Rubner which states: Energy expenditure in warm-blooded species is proportional to the body area of ​​the organism. According to this law, regardless of the size of a warm-blooded organism, the same amount of heat is dissipated from a surface of 1 square meter. Another conclusion from this law is that basal metabolism is directly related to height and weight.

Factors affecting basal metabolism

1) Gender: In men, all other things being equal, the average basal metabolic rate is higher than that of women. This is due to the fact that nature has endowed men with more muscle mass than women.
2) Body structure: Muscle mass is more active than fat mass and requires more energy for its maintenance. The conclusion is you need more muscle, and less fat.
3) Weight: The greater the weight, the greater the surface, and according to the law of the surface, we give off more heat and thus the greater the value of the main exchange.
3) Growth: Growth is one of the components of Rubner's surface law, thus the higher the growth, the greater the basal metabolic rate.
4) Age: Babies have a high SVR. With age, the basal metabolism slows down.
5) Sports and exercise: Systematic exercise helps to improve health, burn fat, increase muscle mass, which will lead to an acceleration of basal metabolism. A good example of a fat burning workout is
6) Nutrition: Fasting or drastically reducing calories will not help you lose weight. But ruining your health and slowing down your metabolism is easy. Which will lead to the fact that you will gain weight more easily or to more terrible consequences such as anorexia.

Summing up the intermediate result. Basal metabolism is the amount of calories consumed by the body in a state of complete rest, to ensure the vital activity of the body, that is, ensuring the functioning of organs and maintaining a stable temperature. Simply put, the number of calories that you would burn if you lay in bed all day is your basal metabolic rate, which depends on the above factors.

How to Calculate Basal Metabolic Rate

There are many formulas for calculating the basal metabolic rate.
The Harris-Benedict formula was described in 1918.

Male equation = [ 13.7416 * weight in kilograms ] + [ 5.0033 * height in centimeters ]
– [ 6.7500 * age (full years) ] + 66.4730

Female equation = [ 9.5634 * weight in kilograms ] + [ 1.8496 * height in centimeters ]
– [ 4.6756 * age (full years)] + 665.0955

Revised Harris-Benedict Equation Formula, created in 1984. More modern.

Male equation = [ 13.397 * weight in kilograms ] + [ 4.799 * height in centimeters ]
– [ 5.677 * age (full years)] + 88.362

Female equation = [ 9.247 * weight in kilograms ] + [ 3.098 * height in centimeters ]
– [ 4.330 * age (full years)]+ 447.593

Formula-Equation of Mifflin-St. Jeor
The modern formula, with the help of which the basal metabolic rate (BMO) is now determined. It is this formula that is used in the HiKi Calorie Calculator program.

Male equation = [ 10 * weight in kilograms ] + [ 6.25 * height in centimeters ]
– [ 5.0 * age(full years)] + 5

Feminine equation = [ 10 * weight in kilograms ] +
– – 161

Now you know how to calculate your SBI, but for accuracy, you need to make adjustments using activity coefficients. That is, we take the value of your metabolism and multiply it by the coefficient from the table. The higher the load, the higher your coefficient.

The two formulas in the calculator below calculate the amount of calories your body needs based on gender, age, body weight, waist circumference, and daily physical activity (or exercise) level.

Female Male What's your gender Your age in years Your height in cm Your weight in kg. Waist in cm minimum physical activity 1-3 times a week physical activity 3-5 times a week physical activity 6-7 times a week hard physical work + training 2 times a dayPhysical activity
Formula

Before proceeding to the calculation, let's define medical terms.

What exactly is metabolism? Metabolism, or metabolism, is a complete process of chemical reactions in the body, which ensures its vital activity, growth, and physical activity.

Basal Metabolism- this is the main metabolism that provides breathing, blood circulation, digestion of human food in a state of minimal physical activity. This is the amount of heat calculated per 1 kg of the human body per day. To carry out the calculation, the experimental patient can be placed in a respiratory chamber or, by measurements, a certain respiratory coefficient can be derived for him.

It is clear that since the metabolism is basal (basic, lower), it is better to conduct an examination at the moment of complete relaxation, in the morning on an empty stomach, and also taking into account those factors that affect the acceleration or deceleration of metabolism. These factors are from the field of endocrinology, and an example is thyroid dysfunction. These diseases affect body weight no matter how much you eat. You can starve, but still be a fat man, and even then there is definitely a direct road to the endocrinologist.

The effect of food intake on metabolism should be considered from the main point of view - the acceleration or deceleration of metabolism.

For example, all food, being a source of energy for the body, thus carries a thermal effect. However, the effect of some foods is much greater, longer: these are carbohydrates rich in fiber, as well as protein foods, such as meat, fish. The body spends about 30% of calories on their digestion - which means that the metabolism works to burn your extra pounds.

There is another indicator glycemic index. It is high in those foods from which sugar is absorbed instantly, going into the blood. These are the so-called simple carbohydrates. But if you consume carbohydrates with a low glycemic index, that is, long-digestible (vegetables, cereals), then the metabolism again works for you, being in good shape.

Calculation formulas:

Muffin-Jeor Formula, derived in 1990, considers this:
P = 9.99 * weight (kg) + 6.25 * height (cm) - 4.92 * age (years) + constant (different for men and women).

Ketch-McArdle Formula takes into account the ratio of muscle mass to body fat:
P = 370 + 21.6 * LBM (kg), where LBM is body weight minus fat.

If you are interested in doing your own calculations, in your opinion, more accurate - calculate the proportion of body fat in your body, using the other health calculators available on the site.

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