CC BY
18https://doi.org/10.32603/1993-8985-2019-22-3-122-129
Nguyen Mau Thach1 Nguyen Trong Tuyen1, Tran Trong Huu2
1Le Quy Don Technical University 236 Hoang Quoc Viet, Hanoi, Vietnam
2Vietnam Military Medical University 160 Phung Hung, Hanoi, Vietnam
METHOD AND SYSTEM FOR ASSESSING OF SPORTSMAN'S PHYSIOLOGICAL RESERVES DURING PHYSICAL EXERCISES
Abstract
Introduction. An assessing of the sportsman's physiological reserve (PR) and its dynamics is important when planning and carrying out a training, forecasting sportsman's results. An importance of this problem increases in highperformance sports, and energy consumption sports. A complexity of solving of this problem is caused by the requirement of taking into account of the complex of the biomedical parameters and formation of an integral parameter. This parameter reflects functioning of various body systems which provide significant income to the sportsman's result achievement.
Objective. Development of the method and the system of PR assessing allowing complex investigation of the PR during the training process.
Method and materials. For achievement of the aim the tasks were formulated and solved using methods of biomedical research and engineering, mathematical processing and analysis of the diagnostically valuable parameters. Results. The complex of the biomedical parameters reflecting sportsman's body metabolism in condition of physical exercises is formed. They are the heart rate, the heart rate variability, the pulse frequency, the systolic and diastolic pressure, the respiratory rate, the blood saturation, and the stress index by Baevsky. It is important for PR assessing to assess parameters characterizing sportsman's physiological reserves at the current moment and its dynamics. The circle diagram is proposed for taking into account of all mentioned parameters and its variation dynamics. The value of the integral PR parameter is an area of a polygon, which is obtained on the circle diagram using normalized values of the diagnostically significant parameters. The method of biomedical investigation of the sportsman and the method of PR assessing based on the complex of the body system parameters are developed. The scheme of assessing of sportsman's body physiological reserves before and after the training is proposed. The scheme allows to assess not only sportsman's body energy consumption during the training but also its recovery after the training. General structures of the biotechnical system and a structures of systems of picking up, registration, processing, and analysis of biomedical signals for assessing of sportsman's physiological reserves are developed. Special attention is given to the development of a wearable device for synchronous registration of the complex of biomedical parameters and algorithms of assessing of the diagnostically significant parameters of sportsman's body physiological reserves. Conclusion. The proposed method of sportsman's physiologic reserves investigation and the structure of the system with spatially distributed architecture allow sport medicine doctor and coach to assess an efficiency of sportsman's training process with respect to his potential capabilities, and efficiently control the training process.
Key words: method, system, assess, sportsman's physiological reserves, statistic and dynamic parameters, recovery of physiological and functional reserves
For citation: Nguyen Mau Thach, Nguyen Trong Tuyen, Tran Trong Huu. Method and System for Assessing of Sportsman's Physiological Reserves during Physical Exercises. Journal of the Russian Universities. Radioelec-tronics. 2019, vol. 22, no. 3, pp. 122-129. doi: 10.32603/1993-8985-2019-22-3-122-129
Source of financing. Initiative work.
Conflict of interest. Authors declare no conflict of interest. Received 19.04.2019; accepted 20.05.2019; published online 27.06.2019
© Nguyen Mau Thach, Nguyen Trong Tuyen, Tran Trong Huu, 2019
Контент доступен по лицензии Creative Commons Attribution 4.0 License This work is licensed under a Creative Commons Attribution 4.0 License
Nguyen Mau Thach1 H, Nguyen Trong Tuyen1, Tran Trong Huu2
Le Quy Don Technical University 236 Hoang Quoc Viet, Hanoi, Vietnam
Vietnam Military Medical University 160 Phung Hung, Hanoi, Vietnam
МЕТОД И СИСТЕМА ОЦЕНКИ ФИЗИОЛОГИЧЕСКИХ РЕЗЕРВОВ СПОРТСМЕНА ВО ВРЕМЯ ТРЕНИРОВОК
Аннотация
Введение. Оценка физиологического резерва (ФР) спортсмена и его динамики актуальна при планировании и проведении тренировок, прогнозировании результатов спортсмена. Актуальность данной проблемы усиливается в спорте высоких достижений, в частности в энергетически затратных видах спорта. Сложность решения этой проблемы обусловлена необходимостью учета комплекса медико-биологических показателей и формирования интегрального показателя, отражающего функционирование различных систем организма, которые обеспечивают значимый вклад в достижение результата спортсмена. Цель работы. Разработка метода и системы оценки ФР, позволяющих комплексно изучить ФР во время тренировочного процесса.
Методы и материалы. Для достижения поставленной цели были сформулированы и решены задачи с использованием методов медико-биологических исследований, биомедицинской инженерии, математической обработки и анализа диагностически значимых показателей.
Результаты. Сформирован комплекс медико-биологических показателей организма, отражающих метаболизм организма спортсмена в условиях физических нагрузок. Это частота сердечных сокращений, вариабельность сердечного ритма, частота пульса, систолическое и диастолическое давление, частота дыхания, сатурации крови, индекс напряженности Баевского. Для оценки ФР важно оценивать показатели, характеризующие физиологические резервы спортсмена в текущий момент времени и их динамику. Предложена круговая диаграмма для комплексного учета всех перечисленных показателей и динамики их изменения. Количественной мерой интегрального показателя ФР является площадь многогранника, полученного на круговой диаграмме по нормированным значениям диагностически значимых показателей. Разработан метод проведения медико-биологических исследований спортсмена и метод оценки ФР на основе комплекса показателей систем организма, предложена схема оценки физиологических резервов организма спортсмена до и после тренировок. Она позволяет оценить не только энергозатраты организма спортсмена во время тренировок, но и его восстановление после тренировок. Разработана обобщенная структура биотехнической системы и структуры системы съёма, регистрации, обработки и анализа биомедицинских сигналов для оценки физиологических резервов спортсмена. Особое внимание уделено разработке носимого устройства для синхронной регистрации комплекса биомедицинских сигналов и алгоритмам оценки диагностически значимых показателей физиологических резервов организма спортсмена. Заключение. Предложенный метод исследования физиологических резервов спортсмена и структура системы с пространственно-распределенной архитектурой позволяют тренеру и врачу спортивной медицины оценивать эффективность тренировочного процесса спортсмена с учетом его потенциальных возможностей, эффективно управлять тренировочным процессом.
Ключевые слова: метод, система, оценка, физиологический резерв спортсмена, статические и динамические показатели, восстановление физиологического и функционального резерва
Для цитирования: Nguyen Mau Thach, Nguyen Trong Tuyen, Tran Trong Huu. Метод и система оценки физиологических резервов спортсмена во время тренировок // Изв. вузов России. Радиоэлектроника. 2019. Т. 22, № 3. С. 122-129. doi: 10.32603/1993-8985-2019-22-3-122-129
Источник финансирования. Инициативная работа.
Конфликт интересов. Авторы заявляют об отсутствии конфликта интересов.
Статья поступила в редакцию 19.04.2019; принята к публикации 20.05.2019; опубликована онлайн 27.06.2019
Relevance. The body physiological reserve (PR) is one of the most significant human biomedical parameter showing energy consumption of the body during physical strain (PS) and the its recovery after end of the exercises. It is advantageous to use the physiological reserve parameter of the body in a sports medicine for assessing of the sportsman's functional reserve. This parameter characterizes the capability of the sportsman to successfully solve assigned tasks. The functional reserves of the sportsman are characterized by his mental strength, skills and experience during solving of the assigned sport task. However, the sportsman's PR role is great, especially in energy consumption sports, as well as in forecasting of the high sporting performance. Therefore, the problem of formation of the biomedical parameters complex, which is significant for PR assessing, and the system for assessing and forecasting of the sportsman capabilities remain actual.
The aim of the investigation is to develop the method and the system of sportsman's PR assessing allowing to investigate sportsman's PR during the training process.
It is necessary to solve the following problems to accomplish a specific aim:
1. Formation of the biomedical parameters complex and the integral parameter characterising sportsman's PR during training process.
2. Development of the method of the biomedical investigation of the sportsman and assess of sportsman's PR based on the complex of body system parameters, which represents body systems functioning.
3. Development of the generalized structure of the biotechnical system and the structure of the system of picking up, registration, processing and analysis of sportsman's biomedical signals.
4. Development of sportsman's wearable device for registration of the physiological parameters complex.
Methods of the problem solving and its results. Formation of the biomedical parameters complex and integral parameter which represent sportsman's PR during the training process.
Carbohydrates are combusting in muscle tissue during the physical activity and aerobic respiration, that leads to production of carbon dioxide, water and heat emission. Continuous intake of carbohydrates and oxygen to the body cells is necessary for realization of this biochemical reaction. Cardiovascular system and respiratory system play an important role in providing of the physical activity. Heart rate (HR), pulse frequency (PF), and respiratory rate (RR) increase while increase of the physical strain. Circulat-
ing blood provides an income of carbohydrates and oxygen to the body cells and getting a carbon dioxide and a water out. Thus, the body PR in the current moment will be determined, first of all, by the following parameters: HR, PF, RR. HR should be changed according to increase of PS. Efficiency of heart rate control could be characterized by the stress index by Baevsky (SIB) [1], [2]. The first signs characterizing metabolism change during PS are the increase of HR, the change of the heart rate variability (HRV). This signs reflect the mechanism of physiological function regulation in sportsman's body and allow to characterize general activity of mechanisms which change parameters of metabolism for achievement of optimal adaptive response and adaptive reaction of the sportsman's body. The values of HRV depends on the activity of interaction between the sympathetic and parasympathetic parts of nervous system. Therefore, HRV is characterized by the heart rate stability and maximum heart potential for given value of PS. In addition, the change of the arterial tension (AT) value and HR reflects the income of carbohydrates and oxygen to the body cells required for doing the physical exercises. The value of heart rate reserve (HRres) displays the capability of the body to do physical exercises on maximum strrain level, characterizes training level and sportsman's recovery. The higher HRres is, the greater capability of standing high physical strain, and wider the range of adaptive mechanisms of sportsman's body [3]-[7].
It is important to provide a rhythmical oxygen delivery to the muscle tissue for increase of the sportsman's performance capability and achievement of high results during the physical activity. It is no coincidence that blood doping is used in many sport discipline that allows to increase the number of erythrocytes. This leads to increase of oxyhemoglo-bin level and oxygen delivery, and allows muscles to perform more stable and decrease its fatigability. The key effect of the procedure is the increase of sportsman's performance. Although the blood doping does not increase the maximum strength, it allows muscles to perform more intense during long time without tiredness. Therefore, the arterial blood oxygen saturation, blood saturation (BS) is important parameter for assessing of sportsman's status. Increase of PS leads to decrease of sportsman's BS. It is necessary to provide larger volume of oxygen to increase training duration but the respiratory systems could not provide it. According to this, application of oxy-hemometry tools is important for control of BS and physical activity, because the estimation of sports-
man's BS dynamics is of a great importance not only during training process but also during recovery period [4], [8]-[10].
The next group parameters, which is changing under the PS influence and characterize oxygen transport system, are RR and duration of inspiration and expiration. The control of sportsman's breath is one of the main tasks of the sport medicine and highperformance sport. Frequency decreases rapidly during the recovery. Therefore, determination of RR dynamics is of the great importance for assessing of sportsman's reserves because of the high information capacity of this parameter [11]-[14]. Thus, the next valuable PR parameters are RR and BS level.
It is important to take into account the performance capability of the recovery during sportsman's monitoring for complex assessing of his PR. The recovery rate is determined by the health status, the training level and PR level of the surveyed sportsman. The following dependence could be observed: the higher body PR is; the quicker recovery up to initial conditions of enhanced PR proceeds. Thus, the following physiological parameters characterizing PR of the body must be used for assessing of sportsman's PR: HR, PF, HRV, SIB, SAT and DAT (the systolic and diastolic AT), RR, BS level. These parameters should be used for integral assessing of sportsman's' body PR.
It is necessary to do a normalization of the particular parameters for integral assessing of the PR by the complex of the diagnostically significant parameters, because they have different dimension. Each of the particular parameters must be estimated not by its absolute value, but using relative scale. The variation range of some of the parameters is the tenth of unit, others is dozens and hundreds. That requires to represent these parameters at the same scale. Therefore, it is suggested to go from the absolute values of HR, PF, HRV, SIB, AT, RR, and BS level to the relative values by using normalization in the terms of chosen values. For example, a particular sportsman's maximum or a particular age-group limit. For example, HR is set to be 190, SAT is set to be 200 mm Hg, RR - 40 breaths per minute, etc. Relative values of particular parameters after normalization will be in the rangy from 0 to 1.0.
Let Pi (t) is the current absolute value of the particular parameter characterizing sportsman's PR, i = 1, N; where N is a number of parameters used for assessing of sportsman's PR, then the relative current particular value of parameter is derived by the ex-
-PF
SAT
Fig. 1. Graphic representation of the integral PR parameter p . (t)
pression pi (t) = —'--, where P\im is the limit
Plim
value of the particular parameter. Integral PR parameter IPpr (t) could be determined either as the convolution of the particular parameters IPpr (t) = = P1 (t)P2 (t)••• PN (t) =nPi (t) or the vector in
N-dimensional feature space or the N-sector circle diagram. In the latter case, integral parameter is characterized by the area of the N-sector diagram (Fig. 1).
The integral PR parameter IPpR (t) is the current value of PR, which is determined by the current values of the particular parameters. Assessing of PR values before training, during training in the moments of the dozed strain change, and after training allows to investigate the reaction of sportsman's body response to various levels of the dozed strain, and adaptive mechanics of the body for acting in extreme conditions. The following sportsman's PR parameters are of the interest for the coach and the sport medicine doctor (SM) - before the training (background value), during the training, after the training, and recovery of sportsman's PR after intensive training. In this connection, it is advantageous to estimate the values of the body PR at a particular point in time, the PR dynamics in time intervals during change of the dozed PS, and also PR dynamics during the recovery of sportsman's body after the training (Fig. 2) [7], [11].
Development of the method of sportsman's biomedical investigation and assessing of sportsman's PR based on the complex of the body system
PF
SAT After training
Fig. 2. Dynamic Parameter of Sportsman's Body PR
parameters, which reflect the body system functioning. During the training procedure the sportsman accomplishes various tasks with PS according to schedule aimed on formation of skills and experience under coach leadership. This process usually includes several stages with brief pauses for task change and PS increase in between. It is important to know for the doctor and the coach how the sportsman's body PR will change during physical strain increase [15]-[17]. The quantity of the training procedure stages depends on a variety of factors: the training schedule, the sport discipline, sportsman's health status, etc. Let us use the following simplified scheme (Fig. 3) for explanation of the methodology of the development of the investigation method aimed on studying of sportsman's body PR.
In accordance with proposed scheme the point in time To, T1, T2, ... , Tk are used for assessing of the sportsman's body potential capabilities.
The point in time To - assessing of the initial (background) value of sportsman's body PR before the training. Training procedure starts right after as-
sessing of PR( To).
The point in time T1 - assessing of the PR(T1 ) after the end of the first stage of the training.
The point in time T2 - assessing of the PR( T2) after the end of the second stage of the training.
The point in time Tk - assessing of the PR( Tk ) after the end of the training process (k-th stage). Then PR (jAt) are assessed on time intervals At for studying of the PR recovery time of the sportsman's body.
It is necessary to carry on following procedure at each stage of investigation of sportsman's body PR [18]:
1. Picking up and synchronous registration of sportsman's biomedical signals, processing and analysis of these signals, estimation of diagnostically significant parameters characterizing body PR: HR, PF, HRV, AT, RR, BS, SIB.
2. Assessing of the particular absolute and relative PR parameters, and the integral PR parameter of sportsman's body. Assessing of the integral PR parameters at different stages of training process, assessing of the characteristics of the PR parameter dynamics and sportsman's PR recovery parameter.
3. Revealing of the laws of changing of the integral PR parameter and the PR recovery parameter depending on the physical strain level used during the training process. Development of the mathematical models of sportsman's body PR changing, which represent the change of body potential capabilities in time.
4. Formation of the schedule and the training process correction with respect to sportsman's body PR dynamics.
Development of the generalized structure of the biotechnical system and the structure of the system of picking up, registration, processing, and analysis of sportsman's biomedical signals. For sportsman's PR research and assessing of his body potential capabilities, the biotechnical system should include the elements providing picking up and regis-
The Point in Time
Source Background
Training Process
Sportsman' s condition
Before 1st After 1st After 2nd Start of End of
Training Training Training Recovery Recovery
Fig. 3. The Scheme of Sportsman PR Investigation Procedure
Formation System of Dozed PS
$
Л
Sportsman
Reading and Registration of sportsman PC
t
s У
/У
/ /
Local Management Loop
/
/ ---------------
Tools for Processing and Analysis of PC and data
SM Doctor
Global Management Loop
Trainer
Fig. 4. Structure of Biotechnical System of Sportsman PR Assessing
tration of sportsman's biomedical signals, processing of the signals and assessing of the diagnostically significant parameters, assessing of the particular and integral PR parameters, assessing of the dynamical characteristics of the integral PR parameter, setting the dozed values of physical strain. Thus, the biotechnical system must have the following general structure (Fig. 4). It includes the below described functions that allow to use proposed system in the tasks of the distant monitoring of sportsman's health status:
- Prolonged continuous synchronous registration of the physiological signal complex (ECG, signals of respiratory movement (SRM), photoplethysmogram (PPG), photo-oxyhemogram, etc.) characterizing current sportsman's PR condition;
- Assessing and storage of the diagnostic parameters in the SM doctor's processing and analyzing device;
- Informational and medical care of the sportsman by SM doctor in the case of a critical condition appearance;
- Rapid review of the training efficiency and the schedule correction carried on by the coach in accordance with the global control loop.
The system assessing sportsman's PR must provide the function of continuous control of sportsman's health status during the training process to eliminate life-threatening conditions of the sportsman. Therefore, the system must have two control levels, which includes both the SM doctor and coach:
1. The first control level assumes the local assessing of PR parameters by using the system of picking up and registration of sportsman's physiological condition (PC) based on sportsman's wearable
device (SWD), the tools for processing and analysis of PC and data based on doctor's laptop computer (DLC). Using this loop, the SM doctor controls the operating regime: picking up and registration of PC, processing method choosing, analysis and displaying of sportsman's PR, choosing and correction of the research process program using the dozed PS.
2. The second loop provides a communication between SM doctor and coach to form sportsman's training activity (training schedule) with respect to the earlier obtained data of sportsman's PR. All sportsman's PR data downloaded to DLC is copied to the server for filling into the stored sportsman's electronic card. Having access to the server, coach can analyze the data of sportsman's PR dynamics during the current training or for a long period of sportsman's training, develop activities and make corrections of the sportsman's training schedule. In the case of emergency threatening to sportsman's life connection between SM doctor and coach must be direct (Fig. 4)
Development of sportsman's wearable device for registration of the physiological signal complex. It is proposed to use SWD, which is the intellectual system for picking up and registration of sportsman's PR, for PR assessing during the training process [19]. Functional purpose of SWD is providing of continuous and synchronous registration of the sportsman's PC complex.
SWD (Fig. 5) provides picking up and registration of SRM, ECG, PPG, muscle activity, characterizing activity of respiratory system, cardiovascular system, locomotor apparatus during the training process. SWR should have minimal dimensions and
ES
г 1 OS 1
ABP
LD
I
PD
APC
CVC
IS ARMS
AS
Fig. 5. Structure of System of Reading, Registration, Processing, and Analysis of Sports-Man's Data
weight, provide usability in the case of the prolonged monitoring, intellectual regimes of picking up, registration, processing, and analysis of biomedical data.
Picking up and registration of ECG is carried out using of the electrode system (ES) and the amplifier of a biopotentials (ABP).
The channel of registration of the wave signals and oxyhemometry includes the optical sensor (OS) based on a light diode (LD) and photodiode (PD), the amplifier of pulsed current (APC), and the current-to-voltage converter (CVC).
The channel of breath registration includes the inductive respiration sensor (IS) and the amplifier of the respiratory movement signal (ARMS).
The channel of muscle activity signal registration includes the digital accelerometer sensor (AS).
All registered signals applied to the input of the microcontroller (MC), analogue signals converts into a digital code using the microcontroller build-in analog-to-digital converter. Then these signals are formed into the files of synchronous recording, which is transmitted to DLC using Bluetooth. It is reasonable to use the low-power microcontrollers for increase of the autonomous functioning of the laptop. Continuous prolonged functioning of the SWD is provided by the autonomous power source (APS).
Thus, the system of assessing of sportsman's body PR have the spatial distributed structure. Such architecture allows to distribute tasks, which are being solved by the monitoring system, to various levels, provide high efficiency of picking up, registration, processing, and analysis of the biomedical signals, assessing of the current value of sportsman's PR level during the training process.
Conclusion. 1. It is necessary to assess sportsman's PR using the physiological signal complexes registered during the training process for assessing of the sportsman's potential capabilities and forecasting of his results. Assessing of the complex of diagnostically significant parameters reflects the efficiency of sportsman's respiratory system, cardiovascular system, and locomotor apparatus. Sportsman's condition should be characterized by the PR parameter in current moment of time, and the dynamics of the parameter during the training process. Assessing of the PR dynamics after the end of the training process allows to assess PR recovery.
2. Proposed method of sportsman's PR investigation and biotechnical structure with spatially distributed architecture allow coach and SM doctor to assess the efficiency of the sportsman's training process with respect to his potential capabilities and efficiently control training process.
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Nguyen Mau Thach - Postgraduate Student of Saint Petersburg Electrotechnical University "LETI". Teacher in Le Quy Don Technical University. The author of 14 scientific publications. Area of expertise: medical instrumentation; biomedical engineering; processing and analysis of biomedical signals. E-mail: thachnguyen@mail.ru
Nguyen Trong Tuyen - Ph.D. in Engineering (2018), Teacher in Le Quy Don Technical University. The author of 29 scientific publications. Area of expertise: medical instrumentation; biomedical engineering; processing and analysis of biomedical signals. E-mail: nguyentuyen1988@gmail.com
Tran Trong Huu - Ph.D. in Engineering (2018). Fellow Worker in Vietnam Military Medical University. The author of 27 scientific publications. Area of expertise: medical instrumentation; biomedical engineering; processing and analysis of biomedical signals. E-mail: trantronghuu2007@gmail.com
