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AN­T RO­P O­M O­T O­R Y­K A
2012
REACTIONS OF THE CARDIOVASCULAR SYSTEM
DURING PHYSICAL EDUCATION CLASSES IN FIRST
GRADE PRIMARY SCHOOL CHILDREN
REAKCJE UKŁADU KRĄŻENIA W CZASIE LEKCJI
WYCHOWANIA FIZYCZNEGO U UCZNIÓW PIERWSZEJ
KLASY SZKOŁY PODSTAWOWEJ
Paweł Chmura*, Andrzej Rokita**,
Marek Popowczak***, Ireneusz Cichy****
**** MA, assistant, Faculty of Team Sports Games of University School of Physical Education in Wroclaw, Poland
**** Professor, PhD, manager, Faculty of Team Sports Games of University School of Physical Education in Wroclaw,
Poland
***** PhD, lecturer, Faculty of Team Sports Games of University School of Physical Education in Wroclaw, Poland
***** PhD, lecturer, Faculty of Team Sports Games of University School of Physical Education in Wroclaw, Poland
Key words: early school education, physical activity, heart rate, effort intensity, Polar Team 2 System
Słowa kluczowe: edukacja wczesnoszkolna, aktywność fizyczna, częstość akcji serca, intensywność
wysiłku, Polar Team 2 System
SUMMARY • STRESZCZENIE Aim of the study. Our study was aimed at the analysis of heart rate in school children aged 7 years in
connection with the reaction of the circulatory system to running games employed during physical education
classes.
Material and methods. Our research was comprised of a group of 100 pupils aged 7 years attending first
grade in primary school. During physical education classes, we registered heart rate by means of the Team
2 System of the Polar Company. Five subsequent games of a running nature were introduced. Between the
particular games, there was a 1-minute break each time for regeneration. Prior to the research, written consent
of the participants’ parents was obtained. All the children had valid current medical certificates.
Results. The maximum average heart rate, amounting to 192.2 ± 14.5 beat/min, was observed during the
15th minute of the physical education class. In the cross-section of the first 3 games, we observed a significant
increase (P ≤ 0.001) of heart rate in relation to the rest value. The applied physical load in the next 2 games
brought about a decrease of the studied index. The lowest average heart rate, amounting to 142.6 ± 16.8 beat/
min, was registered during the break between the third and the fourth games.
Conclusions. The conducted research showed a large changeability of intensity of effort during the implementation of the particular running games. This was proven by the sinusoidal course of heart rate. The highest
average value of heart rate occurred during the third game, which can indicate the maximum stimulation of
the cardiovascular system. The recreation processes after the first 3 running games are similar to one another,
but after the completion of the fourth one they distinctly slow down, which may indicate the growing fatigue
of the participants.
Cel pracy. Analiza częstości skurczów serca u siedmioletnich dzieci, jako reakcja układu krążenia na zabawy
ruchowe o charakterze bieżnym w czasie zajęć z wychowania fizycznego.
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Paweł Chmura, Andrzej Rokita, Marek Popowczak, Ireneusz Cichy
Materiał i metody. Badaniem objęto grupę 100 siedmiolatków, uczniów pierwszej klasy szkoły podstawowej.
W trakcie zajęć z wychowania fizycznego rejestrowano częstość skurczów serca za pomocą urządzenia Polar Team
2 System firmy Polar w czasie pięciu kolejnych zabaw o charakterze bieżnym. Po każdej zabawie zastosowano
1-minutową przerwę w celu regeneracji organizmu. Badanie poprzedziło uzyskanie pisemnej zgody rodziców
uczestniczących w nim dzieci. Wszyscy uczniowie mieli również aktualne zaświadczenia lekarskie.
Wyniki. Maksymalną średnią częstość skurczów serca, czyli 192,2 ± 14,5 uderzeń/min, stwierdzono w piętnastej minucie zajęć. Podczas pierwszych 3 gier odnotowano znaczący wzrost (P ≤ 0,001) skurczów serca w stosunku
do wartości spoczynkowej. Zastosowane obciążenia fizyczne w kolejnych dwu zabawach spowodowały spadek
badanego parametru. Najniższą średnią częstość skurczów serca, tj. 142,6 ± 16,8 uderzeń/min, zarejestrowano
podczas przerwy między trzecią i czwartą zabawą.
Wnioski. Przeprowadzone badania wykazały dużą zmienność intensywności wysiłku w czasie poszczególnych
zabaw o charakterze bieżnym. Świadczy o tym sinusoidalny przebieg zmian częstości skurczów serca uczestników badania. Najwyższą średnią wartość uderzeń serca odnotowano w trzeciej zabawie, co może wskazywać na
maksymalną stymulację układu sercowo-naczyniowego. Tempo procesów regeneracyjnych po pierwszych trzech
zabawach o charakterze bieżnym było do siebie podobne, ale po zakończeniu czwartej zabawy bieżnej zachodziło
wyraźnie wolniej, to zaś mogłoby świadczyć o rosnącym zmęczeniu uczestników.
Introduction
In our times, human beings attach more and more significance to being healthy and competent for a long
time. More and more frequently we appreciate physical activity as an indispensable element influencing the
quality of our lives. Those of us who on a regular basis
improve fitness by swimming, running, or practicing other sports have fewer health problems. Also, our level of
self-assessment is higher, we look positively into the future, and we are happier than other persons of the same
age. It seems that the formation of appropriate physical
habits at a young age shall pay off in older age.
Parents want their children to develop well. The
recent dynamic developments of modern technologies and computerization of virtually every domain of
life contributes to the fact that especially children and
young people spend more and more time in front of
TVs or computers, much more than the amount of time
they devote to active relaxation in the open air. On the
one hand, it can result in unattractive forms of spending free time as proposed by the parents, while on the
other hand, there is little interest in developing physical activity and formation of appropriate pro-health
customs. This is also connected to the fact that kindergartens and schools are attended by children whose
physical skills are much worse than several years ago.
Additionally, children’s activity is adversely influenced
by sedentary behavior and their need for spontaneous
movement, which decreases with age. In accordance
with new criteria, school children and youth ought to
engage in moderate and high intensity effort exercise
for 60 minutes per day in a form that is adjusted to their
developmental stage and that is diverse and constitutes
a source of joy [1]. Results of research by Przewęda
and Dobosz [2] carried out in the years 1979–1999 in
numerous groups of children and youth (aged 7.5–19.5
years) in Poland indicate a visible regress of physical
fitness and physical efficiency with youth.
In an attempt to prevent this phenomenon from developing and to make children attending first grades in
the integrated education better absorb new information in
the educational process, we employed the research project “Educational balls – edubal,” by Rokita and Rzepa.
Based on this project, the University School of Physical
Education in Wrocław introduced classes aimed at familiarizing future teachers with educational balls. These balls
contribute to the development of children’s skills in the
scope of simple mathematical operations and basic issues of the Polish language. They teach how to apply the
acquired knowledge in practice, think creatively, and they
also motivate youth to engage in physical activity [3, 4].
Play (including playing with balls) accompanies
a human being beginning in early childhood. It does
not only add colour to life, but also introduces joy, relaxation, and motivates one to make an effort. It also
supports the general physical and mental development
of a child and triggers his/her spontaneous activity. As
early as during early school education, i.e. in grades
I–III, we can observe diverse behavior in children.
Some of them are eager to cooperate and actively seek
partners to play with. Some do not show any initiative
and passively look at other children. Borecka-Biernat
and Węgłowska-Rzepa [5] determined and described
styles of functioning in a group, i.e. managing style, cooperating style, subordinating style, withdrawing style
and destructive style, as relatively constant behaviors
of persons during the performance of mobile activities.
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Reactions of the cardiovascular system during physical education classes in first grade primary school children
School education ought to ensure the extensive development of a child by carrying out tasks in the scope of
acquisition of knowledge and skills in a harmonious and
comprehensive way. Is this so in reality? In this study
we shall attempt to answer a few key questions.
This study was aimed at analyzing heart rate in first
grade primary school children in connection with the
reaction of the circulatory system on running games
employed during physical education classes as well as
answering the following questions:
1. What is the reaction of the cardiovascular system to
the applied running games?
2. What is the maximum heart rate reached by children during the particular games?
3. What is the dynamics of restitution processes upon
completion of each running game?
Research material
Our research comprised a group of 100 pupils attending
first grades of the following primary schools: Primary
School No. 1 and Primary School No. 2 in Wołów. The
children participated in physical education classes in
accordance with the class scenario previously agreed
upon by the teacher. The participants were aged 7
years (born in 2003). Their body weight ranged from
18 kg to 45 kg, and their height ranged from 114 cm to
143 cm. Prior to the research, written consent of the
participants’ parents was obtained. All the children had
valid current medical certificates.
Research method
During physical education classes we registered heart
rate by means of the Team 2 System of the Polar
Company. Recording the data from all the transmitters took place wirelessly and in real time to the base
station from which the information was recorded on
the computer upon completion of the class. The class
time was 45 minutes; however, due to organizational
issues – special belts had to be put on each child with
the purpose of transmitting activity potentials of heart
rate – the effective time of measuring the effort intensity was 27 minutes. The project, which assumed the
realization of pilot research, took place every month
from September 2010 through February 2011 (before
the research proper, the same class scenario was conducted 6 times). During the first class, an employee of
the University School of Physical explained the previously agreed upon class scenario to the children and
the particular class tutors. The program of a lesson unit
comprised 5 running games, and it was consistent with
the principles of lesson plans. The research proper was
carried out in March 2011.
Course of research
The research examinations were started with a 3-minute measurement of heart rate at rest in a cross-legged
squat position. The lowest value of the examined index was taken for the analysis. Each part of the class
was started by the teacher with introductory exercises:
a 1-minute trot around the classroom and 1 minute of
gymnastics performed in the same place. Next, 5 subsequent games of a running nature were introduced, i.e.
Little Tail, Avalanche Tag, Bewitched Tag, Tag with Ball,
Tag in Pairs [6]. Each game lasted 3 minutes. After the
first, second, third and fourth games were completed,
there was a 1-minute break each time during which the
teacher explained the rules of the next game. In the
last part of the class scenario, which lasted 3 minutes,
the monitored children performed breathing exercises
while marching and, afterwards, while sitting.
The registered research results were subject to
basic mathematical and statistical analysis that determined arithmetical mean, standard deviation, as well as
minimum and maximum values.
Research results
During the first 3 minutes of the physical education
class, the lowest average value of heart rate was
103.3 ± 13.0 (Figure 1). At the initial part, we registered
during the trot the significant (P ≤ 0.001) increase of
HR to the value of 176.9 ± 16.5 beat/min, and then
during the gymnastic exercises there was a decline to
143.9 ± 17.6.
During the main part – when the running play character of the class was realized – we observed a large
changeability of cardiac muscle work. In the cross section
of the first 3 games we noticed a significant increase (P ≤
0.001) of heart rate in relation to the rest value. Towards
the end of the first game, “Tag Little Tail,” the examined
variable amounted to 187.0 ± 16.1; in the second one,
“Tag Avalanche,” it was 189.1 ± 17.5; in the third one,
“Tag Bewitched,” 190.7 ± 15.1. The maximum mean value of HR, 192.2 ± 14.5, was observed during the second
minute of the third game. The highest HR max amounted
to 215 beat/min, and the lowest 144 beat/min. The physical load applied in the next 2 games brought about a de-
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Paweł Chmura, Andrzej Rokita, Marek Popowczak, Ireneusz Cichy
200
190
180
Breathing exercises
‘Tag in pairs’
Break
‘Tag with ball’
Break
Tag ‘Bewiched’
120
Break
130
Tag ‘Avalanche’
140
Break
150
Tag ‘Little Tail’
Trot + Gymnastics
160
Rest
Heart rate [beat/min]
170
110
100
0
0
3
6
9
12
15
18
21
24
27
Time [min]
Figure 1. Mean values of heart rate during the conducted physical class scenario
crease of the examined index. During the fourth running
game, “Tag with Ball,” we observed a constant decrease
of heart rate, which at the end of the game was 176.4 ±
21.1. The difference of the mean value of HR between
the first and the third minute oscillated around 8.0 beat/
min and was statistically insignificant. The mean values
of heart rate observed during the last minute of the third
and fourth game varied; this difference was statistically
significant (P ≤ 0.001). The reaction of the cardiovascular
system to the load resulting from the implementation of
the last game, “Tag in Pairs,” oscillated from 181.8 ± 18.5
(during the first minute) to 185.1 ± 18.4 (during the third
minute). The difference between the maximum heart rate
in the third game and the same variable in the last fifth
game was 7.1 beat/min and was statistically insignificant.
Similarly, the difference between the mean value of HR
during the first and the last game was also statistically
insignificant.
Upon completion of each game, a heart rate frequency decreased and oscillated from 142.6 ± 16.8 after the third game to 154.0 ± 12.8 after the fourth game.
The greatest decrease of the examined variable, which
was observed after the third game, was as high as
48.1 beat/min; the lowest was observed after the fourth
game, 22.5 beat/min (Figure 1).
The analysis of the final part of the implemented
physical education class scenario showed a statistically significant (P ≤ 0.001) decrease of a heart rate in
the cross section of a 3-minute regeneration process
from 185.1 ± 18.4 beat/min after the fifth game to 123.9
± 13.2 beat/min. During the last minute of the final part
the diversity of the examined index oscillated from 62
beat/min to 153 beat/min. A heart rate registered during
the last minute of the final part was on average higher
by 20.6 beat/min in relation to the lowest value of the
initial part.
Discussion
The analysis of the research results indicates a large
changeability of the classes, which is evidenced by the
course of changes of heart rate. Throughout the 3 sub-
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Reactions of the cardiovascular system during physical education classes in first grade primary school children
sequent games, i.e. up to the eighteenth minute of the
effort, the studied variable is on the increase, whereas
during the last 2 games intensity slightly decreases between the 20th and 25th minute of the physical education class. HR decline may be caused by emerging
tiredness in organisms of the examined children. We
can suppose that the highest average heart rate (192.2
± 14.5 beat/min) that was revealed during the third running game reflects the maximum stimulation of the circulatory system. Similar values of HR were observed
by Akdur et al. in Turkish children [7].
It must be emphasized that heart rate in children is
significantly higher than in adults, both at rest as well
as during physical effort. This results from, inter alia,
sinoatrial node cells excitability and biological development. Excitability of these cells decreases with age.
Heart work also shows individual personal diversity. It
depends on many factors: biological development level,
body mass, gender, nervous system structure, personal
characteristics, level of physical efficiency, health condition, etc. [8]. Changeability of heart work, expressed
by the abbreviation HRV (Heart Rate Variability), is subject to change depending on emotions, body position,
digestion function, thermoregulation changes, altitude
above mean sea level, climate, as well as various disease conditions such as diabetes, post-infarction state,
ischemic heart disease, and arterial hypertension [9].
In the accessible literature on the subject, we have
not found any publications in which the issue of a curve
intensity of physical education classes of first grade
primary school children would be analyzed. Therefore,
our research results cannot be referred to any literature
examples. There is only some research in this regard,
but referring to older children [10–13]. Upon analyzing
a large population of British children, Van Sluijs et al.
[14] concluded that physical activity with 10-year-old
children in British schools was greater than in these
schools that had a good sports basis. Hobin et al. [15]
emphasized the necessity to attend physical education
classes at least twice a week in order to keep physical activity at an average or high level. Pate et al. [16]
presented research aimed at providing information
on existing methods of measuring physical activity of
kindergarten children. They proved that systems of direct observation of physical activity – accelerometers
– are reliable and commonly recognized methods of
measurement, both in the case of older and younger
children. They also stated that pedometers and monitoring of a heart rate turned out to be very helpful when
controlling physical activity. Among Polish researchers
who have dealt with the topic of physical activity, motor
skills and health of children and young people, we can
mention, among others, Raczek [17]. On the basis of
his own research, he concluded that strength with children, especially with girls, is a feature that is particularly
neglected, and consequently, it is unfavorable with the
functioning of the circulatory system. Relatively low, but
systematically applied strength exercises can lead to
some favorable changes in the cardiovascular system.
Our research indicates that the employed games are
a significant method of increasing adaptation of the
circulatory system with children aged 7 years during
physical education classes in school conditions.
Controlling intensity during physical education classes
has thus far only been conducted by teachers occasionally, and its effects have not been fully objective. When evaluating the class intensity, a dominantly used method is an
intuitional one, on the basis of which a teacher evaluates
child’s reactions to the applied exercises. Measurement of
heart rate by means of palpation on carotid or ray artery
does not solve the problem because of difficulties in performing accurate measurement. The teacher is unable to
carry out these examinations on all the pupils. Individual
measurement by each child is even more error-prone, as
children have neither the experience nor the necessary
skills. Thanks to current technological developments, it
is now possible to monitor cardiac performance in real
time in an accurate and objective way. The teacher is able
to control and correct children’s reactions to the applied
loads and introduce modifications during physical education classes as necessary [18].
In the cross section of our research, we revealed
significant individual differences in heart rates during
the conducted physical education class scenario in its
main part. We could ask why there is such a great diversity of the studied variable. Is it the effect of the loads
applied during physical education classes or rather the
children’s behavior and involvement? Our research
proved that the children’s level of involvement in physical education class is varied. Within the groups, we
revealed a visible diversity with regard to the functioning of individuals in a group. Some of the children are
characterized by a managing style, and they are very
active not only in the research process but also during
the organization of the conducted research. Some of
the children revealed active behaviors directed towards
cooperation without assuming a managing role (cooperative style). Yet another group of children, with regard
to their activity in the group, can be perceived as passive (subordinate style). These children are quiet and are
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Paweł Chmura, Andrzej Rokita, Marek Popowczak, Ireneusz Cichy
limited to only following the teacher’s instructions. They
do not reveal their emotions connected with the performed tasks. It is also possible to notice another group
of children who are not eager to take part in the class
and require additional educational measures (withdrawing style) to be motivated to act. There are very few children who reveal active behaviors that are not connected
with elements of integration with the group – these children disturb the class by introducing some destructive
elements (destructive style). Such behaviors are not directed towards common performance of a group task [5].
All of the aforementioned behaviors directly influence an
individual curve of physical education class intensity and
constitute reasons for such a great diversity of heart rate
during physical education classes.
The physical activity of the participants was also significantly influenced by the nature and form of the conducted games as well as competition and rivalry in the
particular physical games. We could even say that high
motivation and desire to achieve the best results were
more important than the growing tiredness. During the
phase of grade one primary school, the children are characterized by various levels of awareness. Also, personal
direct contacts of a pupil with the teacher had a direct
influence on physical activity. Despite many messages
addressed to the children by the teacher, some of the
children did not perform the proposed games. It largely
depended on their personality and temperament.
We can assume that the effort intensity curve is a result of various levels of adaptation to the loads applied
during physical education classes as well as the diversity
in fitness and efficiency of the particular children. Through
observation we can conclude that with some of the children who were fitter and more efficient the applied stimulus did not result in maximum stimulation. Those children
who were less fit and morphologically different from their
peers were quicker in getting tired and were unable to
release high effort intensity in the subsequent running
games. Summarizing, we can conclude that various dynamics of the young organism’s biological development
and diverse levels of effort abilities have a significant impact on the reaction of the cardiovascular system on the
loads applied during physical education classes.
After each 3-minute running game we noticed a significant decrease in heart rate. This is the effect of the
break during which the children rested in a sitting position while the teacher explained the rules of the next
game. During the first 3 breaks the mean value oscillated around similar levels (146.7 ± 16.1; 143.0 ± 19.0;
142.6 ± 16.8), which indicates the organism regeneration
processes are on a relatively constant level. This means
that the generated tiredness still had nothing to do with
dynamics of recreation processes. Upon completion of
the fourth game, we observed lower dynamics of regeneration in children. This is further confirmed by achieving
a significantly higher mean value of a heart rate (153.9 ±
12.9 beat/min). The difference between the third and the
fourth break was as high as 11.3 beat/min. This proves
the growing tiredness of the participants. It must be
added that during the last minute of the final part of the
physical education class, in which breathing exercises
were conducted to set children’s organisms at rest, HR
amounted to 123.9 ± 13.2 beat/min. The studied variable
was significantly lower (P ≤ 0.001) than the highest value
recorded during the fifth game by 61.2 beat/min. This
dynamic post-effort restitution indicates that during the
implementation of the assumed class scenario no overloading state took place. A heart rate towards the end of
the lesson did not reach the value that was achieved in
resting conditions.
Taking into consideration organizational and didactic difficulties in executing control of physical activity of
grade one primary school children, the research began
only after a 6-month pilot research was completed.
Children and teachers alike for the first time had contact
with this sort of examinations and the newest generation
control and measurement equipment. The first contact
of children with Polar Team2 System, when they had to
put the transmitters on their chests, was rather uncomfortable. During each subsequent class and game the
children paid less and less attention to these devices
and began to accept them over the course of time.
We can assume that persons who reach higher
values of heart rates are able to keep intensity on
a high level in the cross section of the entire lesson
time. Consequently, they are more predisposed to be
professionally involved in playing sports in the future.
Therefore, a very important aspect with children aged
7 years is connected with running numerous games of
various nature that influence fluency and ease of performing movements, speed of adapting to changing situations on the pitch in team games, and ease in learning new physical structures connected with movement.
Conclusions
1. The conducted research proved great variability of
the effort intensity while carrying out the particular running games, as evidenced by the course of
changes in heart rate.
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Reactions of the cardiovascular system during physical education classes in first grade primary school children
2. The occurrence of the highest mean value of heart
rate (192.2 ± 14.5 beat/min) during the third game
may indicate the maximum stimulation of the cardiovascular system.
3. Recreation processes after the first 3 running games
were on a similar level and on completion of the
fourth one they visibly slowed down, which could indicate the growing fatigue of the examined pupils.
Acknowledgements
The aforementioned project is carried out by
the local council in Wołów and the University School
of Physical Education in Wrocław under the title:
“Integrated education with the use of educational balls
edubal.”
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