Dr.Med., Professor A.L. Korepanov¹
Dr.Hab., Professor О.N. Golovko¹
PhD, Associate Professor I.Yu. Vasilenko¹
PhD, Associate Professor S.E. Motornaya^1
1Sevastopol State University, Sevastopol

 

Keywords: adolescent boys, boys, physical development, myocardial functionality.

 

Introduction. The growing popularity of sports and healthy lifestyle among adolescents and young men leads to the advancement of the sports science founded on the conception of the human motor activity age-related evolution and implemented on the basis of anthropic educational technologies [8]. The level of the functional state of the circulatory system can be viewed as a key indicator of balance of the body and environment [1]. A disease that is not timely diagnosed may cause cardiac and vessel pathological changes in a training process [2]. The number of cases of pediatric cardiac pathologies has recently increased [5]. The number of adolescents with high arterial blood pressure increases with age, 50% of students demonstrate an unfavorable response to dosed physical load [6]. The analysis of hemodynamics in adolescents revealed that the cardiac contractility rate depends on the level of physical development and is lower in the children with high growth rates [7]. The students were found to have reduced circulatory efficiency, adaptation potential, and cardiovascular system functional tension [4]. The cardiac remodeling processes in adolescents may cause pathological cardiac transformation, which leads to the development of organic cardiovascular disease [11]. The problem of sudden death remains urgent: 1 out of 50 thousand young athletes dies when training due to heart diseases such as cardiomyopathy, carditis, artery anomalies, etc., that have not been promptly diagnosed [12]. The foregoing determines the relevance of the study of the cardiovascular system functionality in adolescents and young men prior to sports training, as well as the need to develop reliable methods of prenosological diagnostics and prevention of cardiac pathologies in young athletes.

Objective of the study was to make a comparative analysis of the Sevastopol young men’s population heart functionality test data using polycardiography.

Methods and structure of the study. Subject to the study was the sample of 61 people including 13-14 year-old adolescents (n=22), 17-18 year-old first-year males (n=16) and 21-22 year-old fifth-year males (n=23). The study was conducted in the Physiology Laboratory of Sevastopol State University. The cardiac performance characteristics (heart rate, cardiac cycle phase structure indices and myocardial function indices) were studied by means of computer polycardiography using the cardioanalyser MTC-30 (city of Krasnodar) [10]. There were registered 3 ECG leads according to W. Einthoven's system, phonocardiogram (PhCG), and carotid artery differential sphygmogram (DSG). The automated interpretation of ECG, PhCG and DSG was conducted in accordance with cardiac cycle phases. Upon recoding the signals (6.3 s) and entering the testees’ sex, age, height, body weight and blood pressure (BP) indices into the program, the following indices of the cardiac cycle phase structure were determined in accordance with the operating algorithm of the program: asynchronous contraction phase, isometric contraction phase, tension period, ejection period, acoustic systole, total systole, and aortic open valves period. The actual heart rate (AHR) was compared with the due heart rate (DHR) [9]. The following indices of myocardial contractility and myocardial functional status were determined: mean rate of ventricular pressure rise, myocardial strain index, acceleration of blood pressure rise, cardiac contractile reserve, cardiac mobilization rate, experienced stress level, adaptation potential of the cardiovascular system.

Results and discussion. The study found significant differences in the myocardial contractility in adolescent boys and young men (see Table 1).

 

Table 1. Cardiac performance indices (М±m) in adolescent boys,1st- and 5th-year male students

Note: [1] – р<0.05 when compared with the adolescents’ indices, [2] – р<0.05 when compared with the indices of the 1st-year students.

 

The AHR values corresponded to age norms [3] and did not differ significantly in the study groups. At the same time, the DHR values differed significantly in all study groups: they were the highest in the adolescents, mean – in the 1st-year students, the lowest - in the 5th-year students. When comparing the AHR and DHR we found that HR in the adolescents did not deviate significantly from the proper values ​​(deviation equaled 3.4±0.8%). In the students, the deviation was statistically significant (p<0.05), and amounted to 11.2±0.9% for the 1st-year students and reached its maximum in the 5th-year ones (15.7%±1.3%). The degree of variation of the deviation of the AHR from DHR was significantly (p<0.05) higher in the 5th-year students than in the 1st-year ones and adolescents, and significantly (p<0.05) higher in the 1st-year students than in the adolescents. The AHR deviation from the DHR is a sensitive parameter reflecting the nature of sympathetic-parasympathetic relationships, and it increases with the increase of the tone of the sympathetic division of the ANS [10].

The majority of the parameters of the cardiac cycle phase analysis (asynchronous contraction phase, tension period, ejection period, acoustic systole, total systole, and aortic open valves period) did not display any significant inter-group differences; yet, the tendency to the phase of isometric contractility increasing in the 5th-year students in comparison with the adolescents was detected, which correlates with the general dynamics of contractility decrease in the students. Essential intergroup differences were seen from more significant indices of myocardial contractility. Thus, the myocardial strain index was significantly higher in the students versus the adolescents, which reflects the decrease of the myocardial contractility function. The cardiac mobilization rate as the most objective index of myocardium workload was significantly higher in the students rather than in the adolescents. Extra cardiac mobilization in the students, that might be associated with an increase of post-workload by the peripheral vascular resistance, was reflected in the increase in the acceleration of the left ventricular pressure rise, as compared with the adolescents. The adaptation potential of the cardiovascular system, that characterizes the strain of the adaptive-regulative systems of the body in general and the rate of myocardium function economization [1], was significantly higher in the 5th-year students as opposed to the 1st-year students and adolescents (the lower the index, the higher the rate of adaptation). The experienced stress level was above average in all study groups, moreover, in the 5th-year students it was significantly higher than in the adolescents. During the university studies, the adaptation resource of the heart was decreasing while the role of the sympathetic unit of the autonomous regulation was increasing, as confirmed by the significant decrease in the adaptation potential and increased differences between the actual and due heart rate values in the 5th-year students as compared to the 1st-year ones.

Conclusion. The analysis of the parameters of contractility revealed a decrease in the level of contractility in the students as opposed to the adolescents, and its degree increased from the 1st to the 5th year of study. The myocardial performance of the students was less effective than in the adolescents, which was confirmed by the statistically significant increase of the isometric contraction phase, decreased adaptation potential, increased myocardial tension index, cardiac mobilization rate and stress level, increased differences between the actual and due heart rate values in the students as compared to the adolescents. The influence of negative factors on the students (significant information loads, hypodynamia, nutritional disorders, bad habits) results in the tension of the adaptation processes of the cardiovascular system and decrease in its functional reserves. The obtained data on the dynamics of the cardiac functionality and contractility rates in the Sevastopol adolescent boys and young students will be applied to develop the academic training process optimizing models to prevent pathological heart conditions in the adolescent and youth population groups.

 

References

1. Bayevskiy R.M., Berseneva A.P. Otsenka adaptatsionnykh vozmozhnostey organizma i riska razvitiya zabolevaniy [Assessment of bodily adaptive capability and risk of development of diseases]. Moscow: Meditsina publ., 1997, 253 p.

2. Balykova L.A., et al. Izmeneniya serdechno-sosudistoy i immunnoy sistem u yunykh sportsmenov: polozhitelnye effekty L-karnitina [Changes in cardiovascular and immune systems in junior athletes: positive effects of L-carnitine]. Pediatriya. App. «Consilium Vedicum», 2014, no. 4, pp. 20-24.

3. Baranova A.A., Shcheplyagina L.A. Fiziologiya rosta i razvitiya detey i podrostkov. Prakticheskoe rukovodstvo [Physiology of growth and development of children and adolescents. Practical guide]. Moscow: GEOTAR – Media publ., 2006, 432 p.

4. Voronina I.Yu. Sostoyanie serdechno-sosudistoy sistemy u studentov professionalnogo litseya vo vremya proizvodstvennoy praktiki [State of cardiovascular system in professional lyceum students during job practice]. Biologicheskie nauki, 2016, no. 45 (3), pp. 8-10.

5. Dolgikh V.V., Prokhorova Zh.V., Fomina N.A. Rol psikhoemotsionalnykh i sotsialnykh faktorov v razvitii essentsialnoy arterialnoy gipertenzii u podrostkov [The role of psycho-emotional and social factors in development of essential arterial hypertension in adolescents]. Pediatriya, 2011, no. 5, pp. 25-28.

6. Katashinskaya L.I. Funktsionalnoe sostoyanie serdechno-sosudistoy sistemy shkolnikov i studentov g. Ishima [Functional state of cardiovascular system of schoolchildren and students from Ishim]. Vestnik Tyumenskogo gosudarstvennogo universiteta. Sotsialno-ekonomicheskie i pravovye issledovaniya, 2009, no. 3, pp. 175-181.

7. Korepanov A.L. Funktsionalnye pokazateli deyatelnosti serdtsa u podrostkov s raznyimi tempami fizicheskogo razvitiya [Functional indices of cardiac performance in adolescents with different rates of physical development]. Teoriya i praktika fiz. kultury, 2016, no. 12, pp. 49-51.

8. Lubysheva L.I., Zagrevskaya A.I. Kineziologicheskiy podkhod kak metodologiya sovremennoy sportivnoy nauki i praktiki [Kinesiological approach as methodology of modern sport science and practice]. Teoriya i praktika fizicheskoy kultury, 2015, no. 12, pp. 3-6.

9. Sheykh-Zade Yu.R., Zuzik Yu.A., Sheykh-Zade K.Yu. Opredelenie dolzhnoy chastoty sokrascheniy u cheloveka v pokoe [Measurement of due heart rate in man at rest]. Fiziologiya cheloveka, 2001, no. 27 (6), pp. 114-116.

10. Sheykh-Zade K.Yu. Funktsionalnaya otsenka serdtsa v norme i pri rannem skrytom sifilise. Avtoref. dis. kand. med. nauk [Functional assessment of heart in norm and at early latent syphilis. PhD diss. abstract]. Krasnodar, 2001, 19 p.

11. Basavarajaiah S., et al. Physiological left ventricular hypertrophy or hypertrophic cardiomyopathy in an elite adolescent athlete: role of detraining in resolving the clinical dilemma. Br. J. Sports Med., 2006, no. 40, pp.727–729.

12. Maron B.J. Strategies for assessing the prevalence of cardiovascular sudden deaths in young competitive athletes. Int J Cardiol., 2014, vol. 72, pp.173-369.

 

Corresponding author: akorepanov2006@rambler.ru

 

Abstract

Objective of the study was to make a comparative analysis of the youth population heart functionality test data in Sevastopol. Subject to the study was the sample of 61 people including 13-14 year-old adolescents (n=22), 17-18 year-old first-year students (n=16) and 21-22 year-old fifth-year students (n=23). The junior population heart functionality and myocardial contractility test data were obtained by a modern computerized polycardiograph. The test data showed the myocardial activity in the student groups being less effective than in the adolescent group as verified by myocardial stress indices, heart mobilization rates and adaptation resource rates. It was found that the negative trends in the heart functionality and contractility rates tend to stay throughout the academic educational period. The study data are indicative of the cardiovascular system functionality resource notably sagging in the academic educational process. The study findings will be applied to develop the academic training process optimizing models to prevent pathological heart conditions in the adolescent and youth population groups.