CC BY
80
DOI 10.14526/2070-4798-2019-14-1-207-218
The influence of complex step loads on cardiorespiratory system indices of
students-athletes
Elena Yu. Kolchina*
St. Luka State Medical University, Lugansk, LNR kolba76@yandex.ua*
Abstract: Scientific validity of different forms and methods of physical upbringing and necessity of medical control over the athletes' health is the distinctive feature of a national system of physical culture. In this connection it is important to study the influence of systematic physical exercises and sport, in terms of teaching at a higher educational establishment, on a functional state of the main systems of an organism. It is done in order to take into account physical loads effectiveness and correct educational-training process of students. Materials. Studying complex step loads influence on cardiorespiratory system indices of students-athletes. Research methods. Information sources analysis and summarizing, electrocardiography, hemodynamics indices analysis, lung capacity (LC), respiratory excursion and chest circumference; methods of mathematical statistics. Results. The characteristics of ECG indices and their dynamics are defined during the course of physical upbringing among students-athletes. During physical upbringing at a higher educational establishment with sports specialization (basketball, volleyball, powerlifting) within 2 years of studying (2 times a week) the indices of external respiration improve among men. Among women there is some external respiration indices deficiency. The features of myocardium function economization are more distinct in 2 years of sports systematic specialization lessons. The features of function economization and stabilization are more marked among men. We also see the features of myocardium hypoxia among students in terms of the defined over-tension features. Conclusion. Hemodynamic parameters study according to recommended by us methodology, dynamic electrocardiographic observations and real lung capacity comparison with the due one should be included into the volume of medical control over students, who go in for physical culture and sport. Physical culture in a form of sports specialization should be held during a long-term period, especially among people with insufficient cardiovascular system (CVS) functional state. Keywords: cardiovascular system, physical load, students, athletes, lung capacity, respiratory excursion, chest circumference, bradycardia, electrocardiography, hemodynamics.
For citation: Elena Yu. Kolchina*. The influence of complex step loads on cardiorespiratory system indices of students-athletes. The Russian Journal of Physical Education and Sport. 2019; 14(1): 175-185. DOI 10.14526/2070-4798-2019-14-1-207-218
Introduction
Physical culture and sport lessons provide functional state of cardiovascular system and respiration improvement. They provide high level of adaptability to different physical loads. Even in case of some functional cardiovascular system disorders trained people preserve and develop working capacity of their cardiac muscle.
Physical culture at higher educational establishments has to provide healthy, physically fit, physically trained and strong specialists upbringing.
However, physical culture system,
unfortunately, is not perfect and its effectiveness needs thorough study in terms of further development and firm scientific base creation [1;6;8;10].
Material and methods
During 2 years we examined 295 young students (18-26 years-old) of St. Luka State Medical University. 239 students studied according to the program of sports specialization during 2 years, and 56 students had the 1st and the 2nd categories of the corresponding specialization. There were 191 men
and 104 women among the respondents.
In order to characterize cardiovascular system (CVS) state we used electrocardiography results and hemodynamic indices. Functional state of external respiration was characterized by the volume of lungs capacity (LC) in comparison with the due indices. We also studied respiratory
Table 1 - The indices of chi
excursion and chest circumference. All studies were held in the dynamics during 2 years of physical culture and sport lessons.
External respiration indices analysis. The results of observation over the dynamics of chest circumference and respiratory excursion average indices are presented in tables 1 and 2.
t development among men
Research period Chest circumference Chest excursion
M ±0 m M ±0 m
At the beginning of the research 93,5 4,8 0,5 7,31 1,9 0,2
At the end of the research 94,5 5,4 0,5 7,57 1,9 0,1
Table 2 - The indices of chest development among women
Research period Chest circumference Chest excursion
M ±0 m M ±0 m
At the beginning of the research 89,3 2,2 0,3 5,51 1,8 0,2
At the end of the research 83,9 7,5 1,0 6,43 1,5 0,18
The presented in the table results show not evident, but positive dynamics of chest and respiratory excursion development among male students and chest perimeter decrease among female students in 2 years of lessons in sports specialization. Chest perimeters decrease among female students could be explained by excess fat deposition loss as
Table 3 - Weight and height indices dynamics
a result of systematic physical exercises and it is proved by their weight stabilization in terms of the increasing body length increase.
Tables 3 and 4 prove the expressed theory, as the chest excursion among women increased.
Research period Men Women
weight height weight height
M ±0 m M ±0 m M ±0 m M ±0 m
At the beginning of the research 67,8 6,3 0,5 173,4 5,6 0,4 61,8 5,9 0,7 162,3 1,4 0,1
At the end of the research 69,6 6,1 1,5 180,9 8,0 0,6 61,9 6,5 0,7 163,3 1,4 0,8
Table 4 shows that during the observation LC among men increased and achieved the level of due LC. Among women relative real LC decrease could be conditioned by height increase and weight stability. It is proved by the tendency of LC normalization towards due LC. It should be noted that among
women LC was still insufficient by the end of the observation period.
There were no considerable differences in external respiration indices among students depending on the kind of sports specialization. These differences are revealed among the athletes of the highest sports
specialization (the 1st and the 2nd categories). Tables presents the results of the additional studies, held in 5 and 6 prove all mentioned above: the numerator 2 years of systematic trainings. presents the initial indices and the denominator
Table 4 - Real LC percentage towards due LC in liters
Index At the beginning of the observation At the end of the observation
Men
LC % LC towards Due LC 4,5 l. ±0,04 96,4% ±1,0 5,2 l. ±0,05 100% ±0,06
Women
LC % LC towards Due LC 3,8 l. ±0,04 91,1% ±1,3 3,19 l. ±0,03 94,5% ±1,2
Table 5 - External respiration indices among male athletes
Kinds of LC % LC towards Due LC Weight Height
M M (kg) (cm)
sport m m
4,8 0,51 110,8% 11,4 65,8 168,7
Basketball 5 0,6 113% 10,5 66,6 171
5,6 0,54 112% 12,3 79,1 182,8
Volleyball 5,7 0,7 115,8% 9,1 66,6 182,8
4,6 0,47 98,7% 7,4 75,7 164,4
Powerlifting 4,7 0,21 99,6% 9,2 76,2 165
In spite of the fact that for the athletes, sports specialization, not only real LC, but also the who are in the state of sports fitness, it is typical percentage of LC towards Due LC even in terms of to have indices stabilization. We revealed the the existing relatively high initial results. average indices increase according to all kinds of
Table 6 - External respiration indices among female athletes
Kinds of sport LC % LC towards Due LC Weight Height
M m M m (kg) (cm)
Basketball 3,24 3,5 0,6 0,4 102,3% 109,3% 9,1 10,2 51,5 53,9 160 160
Volleyball 4,38 4,5 0,7 0,7 123,2% 128,8% 8,93 7,4 7 7 10 10 172,5 172,0
All this proves considerable reserve capacity of external respiration apparatus among the trained athletes. The presented results of the athletes differ considerably from the same indices among students. It demands special attention during educational process planning at a higher educational establishment. The conditions creation for external respiration apparatus development and
improvement among students-athletes.
Some indices of CVS state indices characteristic is presented according to ECG and hemodynamics. ECG is widely used in medical-sports practice, especially if it is used before and after the dosed loads. According to the final part of the ventricular complex we judge the processes of repolarization, the features of sports heart over-
tension.
The features of hypertrophia, heart rate rhythm disorder, myocardium hypoxia also find the corresponding refraction during sports ECG analysis. They very often surprise scientists with the features of pathology. However, these features have temporary character. They are more often met during the period of introduction and disappear not only during the rehabilitation period, but also in the main part of the lessons. Some authors consider deviations, especially heart rate deviations, the
Table 7 - Initial ECG indices among students-athletes
result of high mobilization readiness of CVS and other systems of an organism [2,4,9].
Results and Discussion
One of the objectives of the research was to define the characteristics of ECG indices and their dynamics during the course of physical upbringing among students-athletes [3,7]. The main initial ECG indices characteristic among students-athletes is presented in table 7.
Groups Basketball players Volleyball players Powerlifters
Indices Men Women Men Women Men
Prevailing rhythm Sinus arrhyth mia Sinus arrhyt hmia Sinus arrhyth mia Sinus arrhyth mia Sinus arrhythm ia
Pulse rate 74,2±0,5 79,0±0,9 77,0±0,9 74,0±0,9 76,0±0,6
P-Q 0,13±0,08 0,12±0,003 0,12±0,05 0,12±0,005 0,12±0,06
0- S 0,09±0,004 0,09±0,007 0,08±0,001 0,08±0,002 0,08±0,003
Voltage R spikes 14,3±1,1 13,0±0,5 13,2±0,9 12,0±0,7 13,0±0,9
Voltage T spikes 3,1±0,1 3,2±0,1 3,5±0,2 3,8±0,3 4,7±0,1
T spike in chest leads giant 30% negative in Vi -9% negative in Vi in 65% negative in V, - 40% etc. - 20% negative and numps in V] U 88% negative in Vi-30%. giant 35%
Stroke volume ind ex in % 95,6±2,9 I04,0±l ,1 99,62±0,9 98,6±0,6 98,0±1,5
S-T in 80%+llmin B Vl2J,4 at isoline/=/ 10%±1 in chest leads = Single +2mm in uy
Presented in the table results don't have any specific peculiarities. However, we should pay attention to giant T spikes in the first and other chest leads (10-20%) together with moderate S-T interval shift for ±1 m/m among volleyball players and among male gymnasts. Women of this group had T spikes form and direction change without S-T interval shift only in the 1st chest lead, which in sports medicine is considered as physiological feature.
Functional myocardium adaptability to 178 physical loads reflect ECG shifts after standard
physical loads fulfillment. Table 8 presents ECG indices. They characterize the reaction to the load of 20 squats within 30 seconds. Considering the reaction to physical load in general, its favorable character should be noted. There was the increased pulse rate within the following limits: 23-27 beats, some sinus arrhythmia increase. It is accompanied by decrease (mostly among those who go in for basketball) or not changed character (among volleyball players and powerlifters), normal volume of stroke volume index preservation (SVI) and almost all respondents had isoelectric S-T interval
position. R and T spikes voltage decrease was among volleyball players (men and women) and powerlifters and steadiness decrease among women and most men. T spikes forms and directions change was mainly in the 1st chest lead. A great number of giant T spikes appeared among male volleyball players. The reaction on the same load at
the end of the observation period didn't have distinct quantitative changes. Sinus arrhythmia increased a little, the volume of reactions decreased (according to pulse frequency), time indices stabilized. There were no pathologic reactions. It in general proves heart muscle function economization.
Table 8 - Reaction to standard load among students-athletes according to ECG indices
Groups Basketball players Volleyball players Powerlifters
Indices Men Women Men Women Men
Prevailing rhythm Sinus arrhythmia Sinus arrhythmia Sinus arrhythmia Sinus arrhythmia Sinus arrhythmia
Pulse frequency +27 +26 +23 +25 +24
P-Q - 0,006 - 0,005 -0,008 = =
O- S -0,01 - 0,005 = = =
R spikes Voltage -0,2 = - 1,2 -0,6 - 1,4
T spikes Voltage = = -0,9 - 1,3 -0,9
Form change Form change
T spike in chest Form change into Vi rarely and orientation in v, 60% of giant into Viand tardy V2 and others. =
Stroke volume Within the Within the Within the Within the Within the
index normal range normal range normal range normal range normal range
C T single = 1-2
¡3 1 in Vi
General dynamics of the initial ECG indices among students-athletes during 2 years of physical upbringing in sports specialization is presented in table 9. For the comparison we studied the dynamics of ECG indices among athletes of the highest sports category. We saw pulse reaction decrease, Т spikes voltage increase among women and R spikes voltage increase among men and also some disorders in repolarization processes.
The initial ECG indices among the athletes of the 1st and the 2nd categories are presented in table 10, reactions to an adequate physical load in
table 11 and the dynamics of ECG indices within 2 years in table 12.
The presented results of the initial indices, reactions to load and the dynamics of the initial results according to ECG indices among qualified athletes have the definite peculiarities and differ from the same indices among students-athletes.
Table 9 - ECG peculiarities among students-athletes
^^ Groups Indices and rhythms Men Women
Prevailing rhythm Tendency to normalization Still sinus arrhythmia
Pulse frequency -4 -6
P-Q + 0,03 + 0,04
O-S -0,016 -0,010
R spikes Voltage + 0,2 =
T spikes Voltage = + 1
T spikes in chest leads In some cases the features of repolarization disorder. Giant spikes appearance
Stroke volume index Became normal = /-/
S-T 50% of shifts became normal = 1-1
Table 10 - The initial ECG indices among the 1st and the 2nd category athletes
ECG indices Basketball players Volleyball players Powerlifters
Men Women Men Women Men
Prevailing rhythm Sinus Sinus arrhythmia Sinus arrhythmia and bradycardia Sinus arrhythmia Sinus arrhythmia
Pulse frequency 65,5+2,4 79,6+3,4 61,1+3,2 64,0+2,7 70,0+2,4
P-Q 0,14+0,006 0,14+0,005 0,15+0,006 0,16+0,01 0,15±0,06
O-S 0,08+0,002 0,07+0,004 0,08+0,005 0,08±0,002 0,08±0,003
R spikes Voltage 11,0+0,87 9,2+0,75 13,0+0,68 10,0+0,82 11,0+0,71
T spikes Voltage 3,7+2,6 2,6+3,1 3,1+3,6 2,1+2,2 3,7+2,1
T spikes in chest leads 50% / - / in Yu in y2 / -/ 20% /-/in Yu Y 70% giant y 20% in Yi /-/, y 77%, in y2.3 /-/y 55% in Yx /-/, Y 70%,in Yi and others 50% /-/in yu Y 50% more than in 2 leads y 30%
Stroke volume index in % 99,9+2,2 98,2±2,8 98,0±1,23 102,0±1,6 98,0±1,56
S-T Y 20-40%+1 displacement - Within +1,0 about 50% Y 50% for -1,0 in Yvti -
The initial results are characterized by sinus rhythm prevalence among male basketball players and sinus arrhythmia among all other respondents (female basketball players, volleyball players-both men and women, powerlifters), slow heart rate frequency, especially among volleyball players, normal time indices (p-Q and Q-S).
ECG voltage, defined according to R spike 9-13 mm, was the greatest among volleyball players.
T spike (volume-2,1-3,7 mm), according to the form of changes (smoothed and negative), mostly in the 1st chest lead and very often in the 2nd and the 3rd chest leads, especially among volleyball players. Stroke volume index is close to 100%. S-T interval in some chest leads has ±1 mm displacement, mainly among volleyball players (50% of the respondents), which is typical for the athletes and is not considered a pathological feature.
Table 11 - Reactions to standard load (in the initial state and at the end of the observation in 2 years, the
1st and the 2nd categories)
Groups Basketball players Volleyball players
ECG indices Men Women Men Women
Prevailing rhythm I- Sinus arrhythmia increase el At the end D S « « D J3 H ÏÏ, Less sinus arrhythmia & At the end a> E es m <U .c H Sinus arrhythmia and ¡P. EL brad.arythmia At the end O) p ce Vj f— B rady vardi a arythirimia and sinus arythmia At the end OJ p ce Vj f—
Pulse frequency +16,8 +4,4 + 17,4 = + 11 +9,8 6,5 +7,0
P-Q -0,008 -0,006 -0,003 -0,006 -0,015 -0,002 = =
Q-S -0,03 -0,06 = +0,05 -0,08 -0,007 = -0,002
R spikes voltage +0,04 = = -0,4 -0,1 = +0,3 =
T spikes voltage +0,4 = + 1,3 +0,1 +0,1 -1,1 -0,6 =
T spikes in chest leads Less changes More changes in Y: T spikes prevalen ce normaliz ation = More changes in V1,2.3,4.5 giant Distinct T spikes nonnalizatio n
Stroke volume index Norm Norm Norm N
S-T N N N Normal.
Table 12 - Dynamics of the main ECG indices within 2 years of training of the 1st and the 2nd category
athletes
Groups Basketball players Volleyball players
ECG indices Men Women Men Women
Prevailing rhythm Sinus The same, but less distinct Prevailing bradycardia Bradyarythmia
Pulse frequency change bradycardia 52,2 /-13,4 76 /-3,6 bradycardia 52,2 /-13,4 61 /-2,4
P-Q shift = -0,01 /-0,01 / + 0,04
Q - S shift /-0,02 / = /-0,01 =
T spike voltage change +3 = +0,6 -0,01
T spike in chest lead Less T spikes changes in chest lead More changes in y 1,2,3.4 More T spikes changes in Y 2.3,4,5 Less changes and hypoxia
Stroke volume index change norm norm nonn increase till 108%
S-T Not great number ±1 m/h The same More often -1,0 in V3.4.5 The same
Some changes of the final part of the ventricular complex prove relative changes of repolarization processes. They were stated among volleyball players in terms of the initial features of over-tension. Less distinct they were among basketball players.
The reactions to adequate standard loads proved good functional adaptation of heart muscle (moderate pulse increase, time indices decrease, prevailing increase and steadiness of R and T spikes voltage, tendencies to T spikes change normalization).
Additional ECG reactions study to standard loads in 2 years of training, in spite of high training level. It is characterized by functions stabilization. It showed more distinct features of heart activity economization (bradycardia and tendencies to bradycardia, time indices decrease in terms of relatively decreased pulse reaction, Rspikes voltafe steadiness, excluding female basketball players' 182 indices; Stroke volume index change stabilization).
Dynamics of the main ECG indices within 2 years also reflects the features of the increasing heart activity function economization. Volleyball players had P-Q interval increase, probably owing to distincs bradycardia in this group.
It should be noted that in spite of some positive shifts, the features of some disorders in repolarization among the examined qualified athletes preserved by the end of the observation. It in our opinion, is the result of intensive trainings and possible violations of the training regimen. They lead to cardiac muscle over-tension.
During the results of the initial research comparison among the 1st and the 2nd category athletes and students-athletes we revealed increased heart rate among students-athletes, increased ECG voltage, less changeable in a form and T spikes orientation. Higher reactions to an adequate physical load were among students-athletes, T spikes form and orientation change after physical load was less distinct among students-athletes, than
among 1st and 2nd category athletes.
The dynamics of ECG indices shows myocardium function economization among students in 2 years of sports specialization systematic lessons at a higher educational establishment, as well as among the athletes of the 1st and the 2nd category. The features of repolarization process disorder are less distinct. However, there is a considerable increase of giant T spikes cases. They reflect the state of myocardium hypoxia.
Students-athletes have the initial features of myocardium function economization during physical culture lessons at a higher educational establishment. The features of myocardium overtension are not distinct in comparison to the features of the 1st and the 2nd category athletes, especially in dynamics. However, some students have real, though relative indices of myocardium hypoxia. It can be conditioned by regimen moments (overtension, irregular nutrition). But it still demands attention and observation [5,7,11,12].
Taking into account all mentioned above, the volume of observations increased owing to hemodynamic state study among students-athletes
Table 13 - Hemodynamic
according to cardiac stroke volume indices (CSV), minute blood volume (MBV) and the coefficient of reaction to physical loads. Coefficients of regulation calculation according to pulse, CSV and MBV helped to reveal the character of CVS compensation abilities among students-athletes and the definite degree of the training level. It is known that hemodynamic indices and the peculiarities of their reaction to physical loads characterize blood circulation state of all organism. The main hemodynamic parameters of CSV and MBV, studied in dynamics, are the indices of CVS functional state and its working capacity [11]. That is why we think that students' hemodynamic indices contribute to general characteristic. The characteristic contribute to CVS functional state and the shifts within 2 years of study and going in for physical culture.
Hemodynamic state was studied among 263 students of St. Luka State Medical University, who studied according to the program of specialization without taking into account sports specialization (among them 163 men and 100 women). Hemodynamic indices are presented in table 13.
indices among students
Men Women
Initial Additional studies Initial Additional studies
Pulse 72,9±55 71,7±,0,90 79,6±0,72 76,8±0,22
P coefficient 1,52±0,005 1,53±0,001 1,5±0,13 1,52±0,027
CSV 68,1±0,43 67,6±0,88 68,1 ±0,8 5 65,40±1,01
CSV coefficient 1,2±0,12 1,27±0,02 1,2±0,015 1,26±0,032
MBV 4,94±0,49 4,8±0,1 5,3±0,086 5,1±0,16
MBV coefficient 2,0±0,07 2,0±0,1 1,3± 2,G±
Systolic pressure (SP) 115,0±0,82 115,4±1,269 114,5± 1,01 111,9±2,319
Diastolic pressure (DP) 68,1±0,19 70,3±0,962 68,5±0,747 67,6±1,85
SP coefficient 1,15 1,16 1,17 1,18
DP coefficient 0,87 0,88 0,87 0,85
The table shows that the average values of cardiac stroke volume correspond with the indices of healthy people of the same age. However, CSV value among students is lower than typical for the athletes results. Pulse and blood pressure were also within the age norm, but without any tendency to bradycardia and hypotonia. Pulse and CSV reaction coefficient reflects favorable character of hemodynamic shifts owing to simultaneous pulse and cardiac output volume reaction.
After two years of systematic lessons according to sports specialization program the following changes in hemodynamics state were revealed: heart rate slow down, some CSV decrease, tendency to relative reaction coefficient increase owing to cardiac stroke volume in comparison to pulse, some MBV volume decrease in terms of predominant MBV reaction coefficient stabilization. In the initial indices of blood pressure and reactions to the load there is also the tendency of stabilization.
Thus, all mentioned above proves CVS function economization (pulse reaction coefficient, CVC, MBV) according to the main indices of hemodynamics and also blood pressure indices stabilization. However, it should be noted that the mentioned shifts demand further attention to hemodynamic parameters using recommended by us reaction coefficient indices calculation and their development by means of further physical culture lessons.
Conclusion
Summarizing all mentioned above we come to the following conclusion: during physical upbringing process at a higher educational establishment in sports specialization (basketball, volleyball, powerlifting) during 2 years of studying (2 times a week) the following indices are improved: external respiration indices are mostly improved among men, women have some insufficiency of external respiration indices.
The dynamics of these indices in comparison with the dynamics of the athletes is not distinct enough. Myocardium functional state among students in the average is good. The features of myocardium function economization are more distinct in 2 years of systematic lessons in
sports specialization. The features of the function economization and stabilization are more distinct among men. Together with the mentioned above students have the features of myocardium hypoxia in terms of the evident over-tension features. The athletes of the 1st and the 2nd category in contrast to students have distinct features of repolarization disorder, the final part of ventricular complex change. It proves partial myocardium over-tension.
Hemodynamic indices among students prove the increasing CVS function economization during 2 years and relative hemodynamic indices stabilization. However, quantitatively these features are not distinctly demonstrated.
We come to the conclusion that during physical upbringing process in sports specialization students. They study at a higher educational establishment. They are functional state of external respiration and CVS improvement.
Two years of physical upbringing course is not enough for the distinct training features formation.
During physical upbringing of students more attention should be paid to respiratory function development and improvement, especially among women.
Hemodynamic parameters study according to recommended by us methodology, dynamic electrocardiographic observations and real lung capacity comparison with the due one should be included into the volume of medical control over students. They go in for physical culture and sport. Physical culture in a form of sports specialization should be held during a long-term period, especially among people with insufficient cardiovascular system (CVS) functional state.
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Author's information:
Elena Yu. Kolchina* - Candidate of Biological Sciences, Associate Professor, St. Luka State Medical University, 91045, LNR, Lugansk, 50-letiya Oborony Luganska str., House ig, e-mail: kolba76@yandex.ua*
