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01. What is health

Traditional clinical medicine fights disease: even if you feel unwell, but there are no obvious pathological symptoms, the clinic doctor will consider you healthy. Engy Health is based on a fundamentally different approach that is used in sports, industrial and space medicine.

You are healthy if you are able to effectively and effectively adapt to changing, often stressful, external and internal conditions. And at the same time functional reserves are sufficient to maintain homeostasis , that is, the integrity of the body's systems.

Health components can be in different training states. And therefore, a special space is distinguished between health and illness - pre-painful, or "prenosological" , conditions. Engy Health records the imperceptible transition from health to pathology and notifies you about it.

You take action on time and return to a state of health when the body itself is already successfully resisting diseases.

What is homeostasis?

The ability of the body to maintain its own integrity and balance, to adapt to stress is homeostasis. This balance, though constant, is dynamic. And our regulatory systems interact continuously to keep the body in a state of health.

What is adaptation?

The property of the body to adapt to changing circumstances. It is a state where the processes of relaxation and tension are in balance, when the body easily tenses to do work and easily relaxes for good rest in order to accumulate energy for subsequent tasks.

What is a resource and
functional reserves?

In a state of relative rest, a person practically does not need to spend energy. But as soon as a task appears, work begins. To solve it and maintain its balance, the body uses functional reserves. These include physiological, biochemical and psychological.

Physiological reserves are the ability of organs and organ systems to change their activity for the optimal functioning of the body at the moment. Biochemical reserves are the possibilities of accelerating or increasing the volume of biochemical processes. Mental reserves are the capabilities of the psyche: the ability to concentrate, increase motivation, withstand emotional stress, control behavior, etc. Simply put, functional reserves are the range of the body's capabilities, changes in the activity of its mechanisms in order to adapt to stress factors.

02. State of the body

The disease does not arise from scratch. Studying the well-being of astronauts before and during flights, scientists noticed that between health and illness, a number of body conditions can be identified, which reflect the degree of readiness to adapt and use their functional reserves:

Premorbid conditions

Adaptation to external factors is unsatisfactory, and functionality is reduced. Homeostasis is preserved due to significant tension of regulatory systems or the inclusion of additional compensatory mechanisms.

Pre-nosological conditions

To maintain health, such conditions already require the mobilization of functional resources, that is, the tension of regulatory systems. The body's adaptive capabilities have not yet been reduced, but the ability to adapt to stress is reduced. Homeostasis is maintained only through additional tension.


This condition is characterized by a sharp decrease in the functional capabilities of the body. Homeostasis is impaired and pathological changes begin to develop at the systemic level. In other words, a person gets sick.

This classification of health conditions is the basis of the Baevsky diagram, a key element of the Engy Health application.


It is characterized by satisfactory adaptation of the organism to the environment. This means that you have enough functionality to overcome stress and overload. Homeostasis is maintained at a minimum voltage of regulatory systems.

Baevsky diagram is a key element of Engy Health application
03. Heart rate

How to measure health status and transition to borderline prenosological states? The answer was given by scientists: the heart. The heartbeat is the Morse code of the body. The heart is a unique organ with its own autonomous conducting system and the only one whose work we ourselves hear.

Through the work of the heart, you can assess the state of the whole organism. The analysis of heart rate variability (HRV) will help with this. HRV allows one to study the mechanisms of regulation through the ability of the heart to effectively accelerate or decelerate. At the same time, we receive invaluable information for a comprehensive health diagnosis.

03.1 Levels of regulation

Here is an interactive diagram of the interaction of external and automatic regulation loops. Hover over an item or arrow to learn more about it,

04. Pulse and methods of its analysis
04.1. Pulse

Pulse is the heart rate per minute. It shows the current level of functioning of the cardiovascular system. An increase in heart rate from 90 to 150-180 beats per minute in healthy people occurs during physical and emotional stress and is called sinus tachycardia.

A decrease in the pulse rate to 59-40 with the correct sinus rhythm is called sinus bradycardia. Among healthy people, it is often seen in athletes. The mathematical analysis of the pulse makes it possible to translate biological processes into the language of numbers and mathematics. At the same time, within the framework of the scientific approach to the analysis of heart rate variability, the following methods are used:

Pulse is the heart rate per minute. It shows the current level of functioning of the cardiovascular system.
04.2. Statistical analysis of HRV

Based on the measurement of RR-intervals (time between two consecutive heartbeats) and NN-intervals (intervals only between normal contractions, excluding interference and arrhythmias), their comparison and obtaining a quantitative assessment of variability. Engy Health uses statistical analysis to determine the Stress score


standard deviation of all NN intervals. It reflects all periodic components of variability during the recording, that is, it is the total HRV indicator.


evaluation data comparing NN-intervals.


the ratio of NN slots that differ from each other by more than 50 ms, with a total of NN slots.

Fashion (Mo)

corresponds to the number of RR-intervals that occur most often, therefore, they allow to assess the real state of the patient's regulation systems.

Mode amplitude (АМо)

shows the proportion of those intervals that correspond to the value of the mode in the total number of intervals for a certain period of time. This parameter reflects the stabilizing effect of centralizing heart rate control.

Variational span (VAR)

corresponds to the difference between the duration of the largest and smallest intervals.

04.3. HRV spectral analysis

Allows you to quantify the impact on the heart of various regulatory systems . According to the results of the application of the Fourier analysis, several components are distinguished that correspond to fluctuations in the heart rate of different frequency:

The HF component is associated with respiratory movements and reflects the influence of the vagus nerve on the heart, that is, the parasympathetic nervous system. Fluctuations in its activity give rise to changes in the heart rate with a frequency (0.150.4, Hz) and more, forming fast waves (HF - high frequency).

The LF component shows mainly the effect on the heart rate of the sympathetic nervous system and the oscillations caused by it (0.04 - 0.15, Hz), they are called slow waves (LF - low frequency).

VLF-components belong to the slowest system of regulation, humoral-metabolic. It produces very low frequency (VLF) waves corresponding to frequencies less than 0.04 Hz.

This indicator reflects the action of various factors, which include, for example, vascular tone, thermoregulatory system, humoral tone and the influence of the central nervous system.

Further mathematical analysis of LF, HF and VLF waves allows you to build a spectrogram. The abscissa shows the frequency of the waves in Hertz, and the ordinate shows the power in milliseconds squared. It is also convenient to visualize the data of the influence of various regulatory systems through the pie chart of the spectral power of the ranges.

04.4. Nonlinear dynamic methods

Engy Health service uses a nonlinear dynamic method to determine the Load indicator (PARS)

05. Engy Health indicators
The scientific basis of the Engy Health platform is based on the use of statistical, spectral and nonlinear dynamic analysis of HRV.

The technique was developed by the Institute of Biomedical Problems of the Russian Academy of Sciences to monitor the health of astronauts, and later received a worldwide vocation in sports and industrial medicine. Thanks to the mathematical methods of pulse analysis, you can measure the following indicators of your health:

ТP (Total Power) = HF+LF+VLF the power of all vibrations together reflects the volume of work done by the heart to adjust the heart rate to the needs of the body per unit of time.
05.1. Energy or Total Power

Energy (Total Power) reflects the readiness of the heart to flexibly change its rhythm, responding to situations that arise under the influence of signals from regulatory systems (parasympathetic system - relaxation, sympathetic system - tension and the centralized regulatory system - humoral system / CNS). The more optimal this indicator, the healthier and more vital you are. The further from it, the closer you are to the possibility of illness.

Physiological significance:

Energy or Total Power - the total power of the frequency spectrum of the cardiac intervalogram after the Fourier transform, it reflects the degree of impact on the heart rate of all levels of regulation.

The volume of work of the heart to adapt to external changes is calculated mathematically. Since this process is provided by 3 regulatory systems, respectively, three parts of the TR indicator are distinguished: HF, LF, VLF.

How is it considered

TP is calculated by spectral analysis of R-R intervals using the formula:

Total Power Indicators

Interactive Scale: hover over the segment to read the full value description


The vital energy is very small. The body's performance is low. You are in the borderline zone between health and the onset of illness.


You are on the verge of exhaustion, as after physical or mental stress. There is very little vitality. With increasing load, the likelihood of health deterioration is high.


The condition is optimal, you are at the lower limit of the norm. There is enough energy to perform everyday tasks, but with a significant increase in the load, the state of health may deteriorate.


Your body easily and successfully copes with any tasks, all systems are working properly, tension and relaxation are in balance. You have excellent vitality and high productivity!


Your regulatory systems begin to overextend. Check the quality of the recording - it should only be made in a calm, waking state.


You have critical indicators - we advise you to repeat the measurement to check its correctness, taking into account all the recommendations.

05.2. Load (PARS)

PARS - Indicator of the Activity of Regulatory Systems - reflects the degree of stress and the amount of body resources that are necessary to maintain health. This is the price that the body must pay for its own recovery, that is, to return to the state of homeostasis.

Physiological significance:
PARS is a complex, integral indicator characterizing the complex activity of regulatory systems (parasympathetic system - relaxation, sympathetic system, humoral system and central nervous system - 3 levels of stress). Each level of tension corresponds to a certain state of the organism's adaptive capabilities and is measured in points. The more points it shows, the more resources the body must spend on recovery and the longer it will take.

PARS is calculated according to the formula:

Level of functioning + Stability of regulation + Vegetative homeostasis + Activity of the sympathetic vascular center + Degree of centralization of control

PARS indicators

Interactive Scale: hover over the segment to read the full value description


Your body is in working order. Regulatory systems are optimally strained and no additional resources are required.


Moderate stress of regulatory systems, which occurs during vigorous work, stress and negative environmental conditions. To further maintain balance, the body begins to expend additional resources.


The condition is optimal, you are at the lower limit of the norm. There is enough energy to perform everyday tasks, but with a significant increase in the load, the state of health may deteriorate.


Regulatory systems are significantly overstressed. Defense mechanisms do not provide an adequate response to stress. Functional reserves are not sufficient to maintain the balance.


Your regulatory systems begin to overextend. Check the quality of the recording - it should only be made in a calm, waking state.

05.3. Stress level

The Stress metric reflects how much you strain in response to stressors now. Basically, it characterizes the activity of the sympathetic division of the autonomic nervous system, which is responsible for reaction and mobilization under stress. This indicator is very sensitive to any, even minor, physical and psychological stress.

Physiological rationale:
Stress is the body's nonspecific response to any problem and consists in the nonspecific need to adapt and restore homeostasis.

Stress level is the degree of physical and psychological stress in response to the sum of stressors at a given time.

How is it counted?

АМо /(2 * Mо* MxDMn), where

Амо (mode amplitude) is the number of cardiointervals corresponding to the mode value, in% of the sample size.

Мо (mod) is the most frequent value of the cardiointerval in this dynamic range, in seconds

MxDMn (variation range) in sec. reflects the degree of variability of values ​​of cardiointervals in the investigated dynamic series. It is calculated by the difference of the maximum (Mx) and minimum(Mn)

Stress Level Indicators

Interactive Scale: hover over the segment to read the full value description


The body's reserves are depleted, so in response to stress, it does not even strain. Your body does not have enough strength to adequately solve current problems. Such results are typical for a person in a state of long-term severe emotional or physical stress. With this value of the indicator, the following are possible: a decrease in immunity, an increase in blood glucose levels, impaired functioning of the cardiovascular system, cognitive and behavioral changes.


Your body is working to the limit. You cope with the load, but at the expense of the supply of internal energy.


You are good at coping with mental and physical stress. The accumulation and consumption of resources in the body are balanced.


The upper limit of the norm - this means the risk of loss of adaptation. Your body copes with psychological and physical stress, but it uses hormonal responses to do so. They can put stress on the circulatory and respiratory systems.


All your strength is thrown into the fight against stress, and its level is above normal. The body's ability to recover resources is very low. An increased tone of the sympathetic system can lead to anxiety, excessive emotionality and general overexertion.


The reserves for recovery are depleted and your body is in an extremely stressed state. The stress level is very high.


Your heart is working hard and the likelihood of damage to the cardiovascular system is high.

05.4. Pulse

Pulse is the number of heartbeats per minute. Varies depending on the degree of wakefulness. Drops to 45-50 strokes during sleep, rises to 180 during significant exertion.

How it is calculated:
The pulse is calculated by the formula:

60 * 1000 * (n/m), где

n - number of NN intervals in the record
m - duration of recording NN intervals
NN-intervals - the intervals between the normal contractions of the heart.

Indicators Pulse

Interactive Scale: hover over the segment to read the full value description


You have critical heart rate indicators - we recommend repeating the measurement to check its correctness, taking into account all the recommendations.


Pulse below normal. Such indicators can be after sleep, with hypothermia, taking medications, hormonal dysfunction. Low heart rate is common in professional athletes.


Your pulse is normal.


The pulse is above normal. This is permissible after exercise. If the heart rate in a calm state consistently exceeds 90 beats per minute, this is a sign of tachycardia.


Resting heart rate is very high. Such values ​​are characterized by a constant feeling of anxiety.

05.5. Balance LF / HF

The indicator reflects the balance of the divisions of the autonomic nervous system: sympathetic (responsible for tension) and parasympathetic (responsible for relaxation). You can see which of the processes - tension or relaxation - prevails at the moment. Balance is one of the most reliable predictors of life expectancy. Can be improved through training.

Physiological significance

Vegetative balance (LF / HF) is the ratio of low frequency (LF) wave power to high frequency (HF) wave power. It is used as an index of parasympathetic and sympathetic balance, which is an estimate of stress at a given point in time.

Indicators of vegetative balance (LF / HF)

Interactive Scale: hover over the segment to read the full value description


Increased tone of the parasympathetic division of the autonomic nervous system. The sympathetic nervous system, which is responsible for mobilizing the body, is unable to activate it. You are exhausted and may be feeling weak, lack of energy, dizziness, or trouble sleeping.


Your indicators speak of a relaxed state, successful recovery. Your body is trained. And although at the moment the parasympathetic system (responsible for rest) prevails, the sympathetic system is also active and ready for mobilization.


The stress and the rest in your life are balanced. The sympathetic and parasympathetic nervous systems work in concert. This indicator is optimal for morning measurements and ideal for evening measurements.


The predominance of sympathetic influence. The body is mobilized. This is normal to measure during a business day, during times of minor stress. If these are the values ​​of the morning measurement, you are gradually using up your reserves.


The tone of the sympathetic system is increased. You may be experiencing significant physical or psychological stress. Difficulty breathing, increased heart rate, blood pressure are likely.

05.6. Blood circulation index

The ability of the cardiovascular system to adapt to stress, its adaptive potential. Based on the basic characteristics of the state of the body. The higher the indicator, the more resources the heart pumps blood and the more stress is required for adaptation.

How it is considered:

according to a formula that takes into account the following indicators:
HR - heart rate
SBP - systolic blood pressure
DBP - diastolic blood pressure
Age - age, years
Weight - body weight, kg
Height - height, sm

Indicators of the blood circulation index

Interactive Scale: hover over the segment to read the full value description


The circulatory system is in optimal condition. She successfully copes with the effects of everyday stress. Internal reserves are sufficient.

2.6 - 3.1

Satisfactory condition of the circulatory system. This means that your body is coping with the effects of stress, but you have to strain. You are probably on the edge of the norm.

3.1 - 3.5

The body does not adapt well to the effects of stress factors - the risk of the onset or exacerbation of diseases increases.


You have critical indicators - we advise you to repeat the measurement to check its correctness, taking into account all the recommendations, and also check the correctness of the entered parameters (weight, pressure).

Engy Health's HRV analysis demonstrates which lifestyle is optimal for you.

06. How to use Engy Health

With Engy Health, you can figure out which regimen is best for you. You will be able to consciously manage your own health, tracking his reactions to stress, diet, sleep, rest, work. Build optimal, individual work / life balance using mathematical analysis of heart rate.

Engy Health and sleep

Heart rate variability varies with quantity, quality and sleep patterns. Thus, using HRV analysis, you can identify the optimal individual sleep pattern for maintaining health.

1. Funtova, I. I., E. S. Luchitskaya, I. N. Slepchenkova, A. G. Chernikova, and R. M. Baevsky. "Study of the functional state of the body during sleep in conditions of prolonged weightlessness. Space experiment Sonocard." Clinical Informatics and Telemedicine 10 (2013): 59-74.
2. Wayne, A. M., K. V. Sudakov, Ya. I. Levin, E. A. Yumatov, G. V. Kovrov, and K. N. Strygin. "Stages of sleep after psychoemotional influences: personality changes." Physiological journal. IM Sechenov 87, no. 3 (2001): 289-295.
3. Voronin, I. M., and E. V. Biryukova. "Heart rate variability during sleep in healthy people." Arrhythmology Bulletin 30 (2002): 68-71.
4. Chouchou, Florian, and Martin Desseilles. "Heart rate variability: a tool to explore the sleeping brain ?." Frontiers in neuroscience 8 (2014): 402.

Engy Health and stress

Stress as such cannot be considered harmful in itself: it is necessary to increase the tone of life. However, frequent stressful situations and negative emotional influences disrupt the normal activity of the cerebral cortex and centers of the hypothalamic region. The weakening of control on the part of the cerebral cortex leads to a significant increase in the excitability of the vasomotor center and, consequently, to a violation of the vascular tone. HRV methods through assessing the state of the sympathetic nervous system and the balance of the autonomic nervous system allow you to identify the level of stress and control it.

1. Meerson, F.Z. (1981). Adaptation, stress and prevention. Science.
2. Sudakov, K. V. "New accents of the classical concept of stress." Bulletin of Experimental Biology and Medicine 123, no. 2 (1997): 124-130.
3. Sudakov, K. V. "Individuality of emotional stress." Journal of Neurology and Psychiatry. Korsakov's CC 105, no. 2 (2005): 4-12.
4. Dimitriev, D. A., and E. V. Saperova. "Heart rate variability and blood pressure in mental stress." Russian physiological journal. IM Sechenov 101, no. 1 (2015): 98-107.

Engy Health and Leisure

What kind of rest do you recover the fastest? When do you urgently need to rest? How long does it take to recover from a heavy load? The HRV method used at Engy Health provides clear individual answers to these questions.

1. Kovalenko, S. A., and L. I. Kudiy. "Features of heart rate variability in persons with different respiratory rates." Human physiology 32, no. 6 (2006): 126-128.
2. Shcherbakov, NS "Analysis of heart rate variability during functional load and rest." Health and education in the 21st century 13, no. 4 (2011).
3. Amirov, NB, Chukhnin, E.V. "Vegetative regulation of the heart rate in healthy individuals at rest and during functional loads." Basic Research 5 (2009)

Engy Health and Nutrition

In pursuit of an ideal figure, we often forget about health. Losing pounds, we harm the whole body, so after a diet and exhausting workouts, the weight returns. Engy Health uses HRV to track the impact of diet on overall health. With Engy Health, you are aware of the impact of diet on energy, tension, resources and body health

1. Karpenko, Yu. D. Dimitriev D.A. "Influence of body mass index on heart rate variability among students under conditions of relative rest and examination stress." Journal of Siberian Medical Sciences 6 (2012).
2. Meule, Adrian, Rebecca Freund, Ann Kathrin Skirde, Claus Vögele, and Andrea Kübler. "Heart rate variability biofeedback reduces food cravings in high food cravers." Applied psychophysiology and biofeedback 37, no. 4 (2012): 241-251.
3. Matsumoto, Tamaki, Chiemi Miyawaki, Hidetoshi Ue, Tomo Kanda, Yasuhide Yoshitake, and Toshio Moritani. "Comparison of thermogenic sympathetic response to food intake between obese and non-obese young women." Obesity Research 9, no. 2 (2001): 78-85.
4. Schulz, André, Diana S. Ferreira de Sá, Angelika M. Dierolf, Annika Lutz, Zoé Van Dyck, Claus Vögele, and Hartmut Schächinger. "Short-term food deprivation increases amplitudes of heartbeat-evoked potentials." Psychophysiology 52, no. 5 (2015): 695-703.

Engy Health and Sports

Do you have enough reserves to start intense training and how long does it take to recuperate, what type of activity best increases your adaptive potential? All this can be investigated using the HRV method and Engy Health service

1. Igisheva, L. N., E. M. Kazin, and A. R. Galeev. "The effect of moderate physical activity on HRV in children of primary and secondary school age." Human physiology 32, no. 3 (2006): 55-61.
2. Pitkevich, Yu. E. "Heart rate variability in athletes." Problems of health and ecology 4 (26) (2010).
3. Shakhanova, Angelina Vladimirovna, Yakub Kamboletovich Koblev, and Svetlana Stanislavovna Grechishkina. "Features of adaptation of the cardiovascular system of athletes of different sports according to the data on heart rate variability." Bulletin of the Adyghe State University. Series 4: Natural-mathematical and technical sciences 1 (2010).
4. Vikulov, A. D., A. D. Nemirov, E. L. Larionova, and A. Yu. Shevchenko. "Heart rate variability in people with increased physical activity and athletes." Human physiology 31, no. 6 (2005): 54-59.

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