VOL. 112, No 1, 39–45, 2010
UDC 57:61
ISSN 0031-5362
Original scientific paper
Pupils’ working postures in primary school
University of Zagreb
Faculty of Forestry
Department for Furniture and Wood Products
Sveto{imunska 25
10 000 Zagreb, Croatia
Danijela Domljan
University of Zagreb
Faculty of Forestry
Department for Furniture and Wood Products
Sveto{imunska 25
10 000 Zagreb, Croatia
E-mail: domljanº
Key words: working postures, sitting
behavior, primary school, pupils, school
furniture design
Background and Purpose: Primary schoolchildren spend most of their
time in classrooms seated in chairs in some manner, but sitting behavior and
working postures of pupils are rarely observed as an important criterion in
school furniture design. Yet, correctly designed workspace for school children is, among others, one of the most important key factors in regular development of all abilities of youths. This research focused primarily on the
pupils’ behavior at work, their movements and frequent activities during
usage of tables and chairs in primary school classrooms, with the aim to
identify main working postures and define them as notable criteria when
designing school furniture for the future.
Materials and Methods: The research was conducted in one elementary
school in Zagreb, Croatia, with 18 pupils from the 2nd to 8th grades. The
method employed was video recording.
Results: Forty-three characteristic postures and semi-postures, classified
in four main groups were recorded. The results showed that there are major
differences in the subjects’ behavior and in the habits of using the task chair
and table with respect to age, gender, daytime, studied subjects, tasks and the
teachers’ behavior.
Conclusions: Design of school furniture must take into account the age
and anthropometrics of the child as well as analysis of characteristic postures
of the pupils as one of crucial design criteria, to be observed both in 3D and
2D system. New school furniture design has to encourage sitting dynamics
and fits psychological, ergonomic, physical, social and cognitive aspects of
their users.
Received March 10, 2008.
n Western cultures pupils have traditionally been seated in school
chairs and tables as in the official »workplace«. Much development
and research on working chairs has been concentrated on office chairs
and vehicle seats, but little has been done in the field of school seating.
Humans spend nowadays from 8 to 25 years in educational environments. Elementary school-aged children might spend approximately
30% of time on classroom activities (reading, writing, listening and
looking at the teacher) (1). Cardon (2) found out that in traditional
school pupils spend about 92% of their working time in static sitting,
3% in dynamic sitting, 3% in active/walking, and 2% in standing position. When assumed for long periods of time, the standard chair-sitting
posture, proposed even by international standards and guidelines (3, 4),
puts considerable stress on the lumbar spine (5).
Danijela Domljan et al.
Above all factors present in the school environment
(such as age, gender, physical and sports activities, television and computer usage, load carrying, food, psychosocial and other factors), inadequately designed school
furniture, as well as anthropometric parameters and spinal (im)mobility, are frequently taken to be the reason of
posture problems, back complains and sitting discomforts (2, 6, 7).
Negative effects of poorly designed school furniture
that result from required lumbar flexion and kyphotic
sitting posture have been realized for a long time. These
negative effects include anatomical, physiological and
psychological maladaptations (8). They can also be explained by biomechanical studies, showing that sitting
with flexed trunk increases the spinal load, compared to
standing, and showing that prolonged static sitting increases intradiscal pressure, resulting in decreased nutrition to the disc (9). Considering that during the pre-school and school life time there are dramatic changes
in humans physical, psychomotor, intellectual, cognitive, emotional and social development (10), when body
heights and proportions change rapidly (11), school children are nowadays at special risk of suffering negative effects due to the prolonged periods spent seated at school
and the formation of poor postural habits. Back pain
caused by incorrect sitting habits has been identified as
the most frequent cause of invalidity in office work (12).
Results of surveys conducted in Croatia some 25 years
ago (10) showed that approximately 30% of schoolchildren attending primary schools and as many as 45% of
secondary schoolchildren exhibited first signs of bad sitting posture. A few years ago the BBC program confirmed the alarming data (13), showing that, due to the
unhealthy sitting posture, about 25% of the UK students
complain of the back and neck pain, headache and loss of
concentration. Yet research confirmed that non-ergonomical body posture in a prolonged sitting generates muscular pains and manifests different musculoskeletal disorders (6). After a prolonged sitting the body becomes
restless in the attempt to find a better position (14). Unfortunately, in traditional schools restlessness is held to
be unacceptable behavior which disturbs the teaching
process in the classroom. It is not interpreted as the biological and biomechanical need of the body (15). Human body is built to move about, not to remain still.
There is not any prolonged position (sitting, standing, lying or other positions) of a body which could be comfortable and painless after a period of time. Also, there is not
any perfectly designed working chair or table in which,
after some time, body fatigue does not occur. Sitting in
inappropriate designed school furniture can only intensify the fatigue.
However, inadequate or »non-ergonomically« designed school chairs and desks are only one side of the »sitting« hypothesis. Difference should be made between
unsuitable and mismatched furniture on one hand and
improper usage of the all kind of furniture on the other.
Pupils’ working postures
If we analyze the first part of the problem, most of the
furniture found in classrooms is not designed or suited to
the anthropometric dimensions of pupils. Many, if not
most, pupils have been found to sit in mismatched chairs
at desks that are not anthropometrically suitable (1, 16,
17, 18, 19). The reasons are: a) rather old furniture,
dimensioned according to old technical standards more
than 20 years ago (20); b) aggravated growth curve of the
young in the last fifty years (11, 21, 22, 23); c) traditional
bureaucratic approach to the purchasing of classroom,
only two sizes of the furniture are needed (lower for the
younger and higher for older pupils) (19); d) limited
budget and suitability for the teaching process (24); unchange furniture design over the decade in which static
sitting was improved (20, 25); etc.
Even when the furniture fits in dimensions, pupils
still sit »incorrectly« and change postures all the time
(26). Also, even if the furniture is designed according to
the most recent ergonomic principles, the pupils complain of back pain and discomfort (1). Since pupils do
not automatically sit properly ergonomic furniture is
provided, they need proper instructions in sitting behavior and body adjustments.
Finally, there is generaagreement that furniture design
is one aspect of a multidimensional problem, (1, 2, 7), and
that the chairs have to allow »active« or »dynamic« sitting
(27, 28), which is regarded to be the major factor in the
prevention of backache and damaged postures. A sitting
child should always have the choice between sitting postures (e.g. relaxed or tense). In the project »Moving school« (2) innovative solutions in classrooms have been
based on different approach to sitting posture. In such a
school pupils have freedom to move, so it has been found
that pupils sit statically only about 1% such sitting was
mainly replaced by dynamic sitting (53%), standing (31%)
and walking around (10%). Also, less backache was detected.
Therefore, chairs and desks used by children for considerable periods of time have to be designed and evaluated very carefully. School furniture has to fulfill a variety
of different demands, such as anthropometric and ergonomic, orthopedic, ophthalmologic, pedagogic, educational, technical, economical and other design parameters.
Unfortunately, in addition to all these demands, behavior and working positions of elementary school pupils during their usual sessions are rarely observed as important criteria in design of school chairs and desks. Only
a few studies investigated the effect of ergonomically designed school furniture on pupils’ behavior and attitudes
(1, 8, 26, 29, 30). Also, their biomechanical (physical)
needs are rarely taken into account.
Present research began with examination of pupils’
behavior during schoolwork and identification of frequent behavioural patterns as well as characteristic body
postures and movements during use of the task chair and
the corresponding desk in their classrooms, with the aim
to identify exact requirements and parameters related to
future design of school furniture.
Period biol, Vol 112, No 1, 2010.
Danijela Domljan et al.
Pupils’ working postures
Eighteen pupils (12 male and 6 female) participated
in the research. The research was carried out in one elementary school in Zagreb, Croatia, from May to June
2005. The subjects were selected randomly from every
class from second to eight, except fourth. All subject were
healthy pupils of average age in relation to grades from
7.5 to 14.5 years. None of the participants experienced
symptoms of back pain, or exhibited any physical disabilities. None of the test subjects had participated in any
previous studies.
The school was equipped with conventional and
available school chairs and desks procured with the approval and control of the Croatian Ministry of Science,
Education and Sports. The school was selected due to
differences in teaching approach (private school with alternative teaching methods which combine teamwork
and individual work); classroom equipment (one sized,
old and low price furniture) and a working number of
pupils in every classroom (working groups with 10 to 20
Pupils were additionally measured to establish whether
the measured types of furniture influenced the behavior
of pupils while seated with respect to their anthropometric dimensions.
Permission was granted from the head teacher of the
elementary school involved and both the parents and
children who participated in the study. Participation in
the study was voluntary and, after explanation of the investigation to the children, teachers and parents, the parents were sent a consent form with the option that their
child can withdraw at any stage.
School furniture
Two types of furniture were found in the school, different in design characteristics of the base, materials and
dimensions. Both types of chairs were of the similar
height of seat, (type a, ha = 44 cm; type b, hb = 45 cm)
classified as height mark 6 according to HRN ENV
1729-1:2003 (31). Desks and chairs were arranged in the
classrooms in form »U«. This enables video recording as
the main method in this study.
Video recording
In every classroom pupils were video recorded during
a single session (for 45 minutes). The lessons recorded
included: Math, Croatian Language/Literature, Physics,
Geography and Chemistry. The lessons were chosen to
minimize disruption and ensure cooperation by teachers
involved. Recording took place in both morning and
early afternoon lessons, from 8.00 AM to 2.30 PM.
Sitting habits, characteristic behavior and body posture of subjects during classroom activities were digitally
recorded using a corresponding recording system. The
Period biol, Vol 112, No 1, 2010.
recording was conducted using a standard digital video
camcorder (MV590 Canon, Canon Electronics Inc., Tokyo, Japan) fixed on a stand, positioned 3.5–5 meters
away from subjects, depending on the object that was being recorded. Given the fact that the desks were arranged
in a »U« shape the camera was placed in a manner to allow recording of three subjects at a time (male and female), of whom two (P1 and P2) were recorded from the
back (frontal plane) and the third pupil (P3) from the
side profile (lateral plane).
During the first ten minutes of the session the pupils
were allowed to prepare themselves to be comfortably
seated. The effective recording time was 30 minutes.
Video recording
The results of the video recording analysis showed
significant differences in the behavior of subjects during
the use of the chair and desk with respect to their age,
gender, time of day, classroom subject, assigned tasks,
and the behavior of the teacher. Furthermore, there was
also a correlation between the anthropometric measurements of subjects, their behavior and the furniture used.
Forty-three characteristic movements, postures and
interim postures were recorded for all subjects regardless
of age and gender, furniture type or the time of recording
(classification and supplement according to Schröder
(26)). All movements and postures were separated in
four main groups:
• Upper body movements (such as movements of the
trunk, head, neck, shoulders or hands)
• Lower body movements (such as movements of
upper leg parts, lower leg parts and feet)
• Whole body movements (e.g. walking or kneeling)
• Occasional movements and postures (not characteristic but recorded, e.g. hopping or extreme bending)
The analysis of the video recording showed that gender had no impact on the frequency of specific activities
and movements. Female subjects were as dynamic as
male subjects. However, the number of movements decreased significantly with age. Younger subjects (from 7.5
to 10.5 years of age) showed a notably stronger need for
active participation in classroom activities. The youngest
subjects (7.5 to 8 years of age, second graders) were not
familiar with »sitting still« during 30 minutes of effective
recording, even when they were recorded during the
Math lesson. They spent as much as 87% of the time
swinging their legs. Also, during the first 5 minutes of recording the subjects started getting up and walking
around unrestrictedly. For this particular age group the
other most common postures were positions in the third
group (the whole body movements) like standing up and
walking; kneeling on the seat with both knees; resting elbows and the whole trunk on the desk with buttocks supported by the backrest, or standing in front (or beside) the
Danijela Domljan et al.
Pupils’ working postures
Figure 1. The number of movements of P12 (f); Pupil 2, second grade, female; recorded during 35 minutes, within 5-minute intervals.
chair, leaning on the desk. The most recorded positions
from the first group of movements (upper body movements) were head supported by both hand; or with both
elbows placed on the desktop (while listening or reading). In lower body movements (second group of movements) the most usual posture was crossed lower legs and
feet under the desk. Leg swinging was almost constant
and subjects hardly used the backrest.
The secondary graders performed simultaneous movements using their upper body which were connected
with the movements of the lower body and coordinated
movements of the whole body. Pupils do not sit still and
conventional at all, they have different body positions
and they move and change their body postures all the
time. There was no time relevance to the number of
movements but the recording showed that there was a
normal physiological relation between all movements.
The number of body movements of subject P12 (f) (Pupil
1, grade 2, female) performed in 5-minute intervals is
shown in Figure 1.
The third grade pupils were recorded during the lesson of Croatian Language. They recorded less movement than second graders in the group of the whole body
movements, but they had much more lower and upper
body movements. They were swinging their legs almost
all the time, but they also raised hands often while participating in the lesson.
Older pupils (from 11 to 14.5 years of age) exhibited
longer time intervals between static sitting which, rele-
Figure 2. The number of movements of P25 (m); Pupil 2, fifth grade, male; recorded during 25 minutes, in 5-minute intervals.
Period biol, Vol 112, No 1, 2010.
Pupils’ working postures
Danijela Domljan et al.
quency = 2.5 minutes) and there was considerably less
»fidgeting« unlike in younger subjects. There was a higher
frequency of positions such as crossed upper legs (knees)
under the desk; crossed lower legs and feet under the table or forward extension of legs.
In seventh and eight grades there were less swinging
and the feet were usually kept close together and resting
under the desk. Feet were flatted on the floor and the upper body bent-over from left to right in the frontal plane,
or the trunk inclined and bent backward and forward in
the lateral plane (Figure 3).
Results confirm that pupils generally do not know a
»unique« and »correct« body posture during classroom
activities. Gender has no impact on the frequency of specific movements, but there are major differences in subjects’ postures and in the habits of using task chair and
desk with respect to their age and anthropometrics, daytime, studied subjects, teachers’ behavior and dimensions of the furniture used daily.
The youngest ones (second grade) know nothing
about »sitting still« or »correct sitting posture«. Figure 4
shows the most usual state in the second grade classroom
during one lesson. It was recorded in the sixth minute of
the lesson. Pupils interrupted monotonous permanent
positions to improve comfort. They changed position every 2 to 10 seconds, in both upper and lower body parts
and even the whole body.
On the contrary, the older subjects were much more
still than the youngest. The fifth graders had less movement with the whole body, but they showed mainly upper and lower body movement positions (Figure 2). The
seventh and eight graders were even stiller than pupils in
the fifth grade.
Figure 3. Some of the usual positions by seventh grade pupils while
reading and writing.
vant to the subject studied and gender, ranged on average
from 17 to 20 minutes of sitting still during which only
movement of the lower and upper parts of the body was
recorded. Figure 2 shows the number of movements of
pupil P25 (m) (Pupil 2, fifth grade, male) recorded during 30 minutes. The fifth grade pupils recorded only upper and lower body movements, with less of the whole
body movements.
In higher grades, uniform movement of the trunk and
head were recorded, i.e., s positions when head is supported by one (or two) hand and one (or both) elbow is
placed on the top of a desk; or when trunk inclination
and bending (backward and forward in the lateral plane)
was related to the assigned task (average movement frePeriod biol, Vol 112, No 1, 2010.
Figure 4. The usual working positions of the secondary graders.
Danijela Domljan et al.
Such differences in the recorded working positions and
pupils’ behavir can be explained by several main reasons
which can also account for the posture of subjects, and indicate that the design of school furniture is only one of the
several factors of the interdisciplinary problem:
Age: During the first 2–3 years of school life, pupils
(from 6.5 to 7.5 years of age) are not physiologically prepared to adopt organized work rules. Their bodies still
require free movement. They are much more restless and
frequently change their body positions (Figure 4). With
growing up and gradual learning of the sitting habits pupils are literally trained in the »appropriate« sitting posture. Consequently, in higher grades there is no more
need for free movements. Static sitting posture becomes
apparent (Figure 3). It could be the main reason why the
older pupils have much more LBP/MSD problems than
younger graders, as detected in other studies (2, 7). From
culturological approach, as we live in the Western society,
any unexpected movement and body posture (such as lying with both shoulders, elbows and head on the work
surface; posture with forward extension of legs, etc.) is
still interpreted as rude and unacceptable behavior and
may thwart teachers’ to keep the class quiet.
Design of furniture: The reason why pupils are stiller
with ags can be explained with mismatch in furniture
and pupils’ anthropometric dimensions. If furniture allows free movements and restlessness, pupils act accordingly. For example, younger pupils are smaller in their
height than the older ones, so shorter pupils seated on
high chairs have swinging legs, mostly because they could
not touch the floor. In our study we only one height of the
furniture (especially chairs) in the whole school. According to standards (31), the height of the chair is defined by
comparison with the popliteal height (or shin height)
measured in sitting position. A chair that was too high
(seat height h = 44/45 cm) in relation to the popliteal
height (F), of second graders (mean F2 = 37.41 cm),
third graders (mean F3 = 38.59 cm), and even fifth graders (mean F5 = 42.32 cm) enabled constant swinging of
the lower part of the legs because their feet could not
touch the floor. On the contrary, the dimension of the
same chairs were suitable and much more matched to
the popliteal height of older subjects, where the seventh
grade boys (mean F7m = 46.19 cm) and girls (F7f = 44.21
cm), or eight grade boys (mean F8m = 46.26 cm) and girls
(mean F8f = 44.32 cm) could put the feet on the floor
(Figure 3).
The time of recording: According to the results of video
recording, pupils were notably quieter and less active
during morning lessons, while in the afternoon they
would lie on top of their desks (especially the younger
pupils) or were more restless. Also, in the first ten minutes of the video recording pupils were more physically
active, so the numbers of movements increased. From the
11th to 15th minute of recording all subjects in all recorded
classes were stiller and the body movements reduced.
They got their tasks, and participated in the lesson (writing or reading). Therefore they recorded only lower or
upper body movements, or even occasionally recorded
Pupils’ working postures
movements such as extreme bending (while copying from
another pupil or whispering). As the end of the lesson approached, they finished the tasks and again started to be
physically active. The reasons might be either they were
physically tired or they were psychically free of teacher’s
The subject being taught and learned also affected the
posture of pupils. For example, proactive behavior during classroom activities and verbal teamwork implied
more physical engagement and hand rising with pupils
even getting out of their seats. Group work for written
tasks requires more pronounced bending of the body
over the desk and towards other pupils in the group.
Contemporary humans spend one third of their lifetime sitting, of which almost 10.000 hours in classrooms.
The purpose of modern designed school furniture is to
provide proper and comfortable seating at matching, under various conditions determined by contemporary curricula, during writing, reading, listening and watching the
teacher, modeling or drawing, in a team- or individual
work, during use of a computer or any other similar activity. In addition to meeting basic requirements (mobility,
portability, maintainability, functional adjustability, etc.,
with satisfactory durability, strength and safety) contemporary furniture has to comply with fundamental ergonomic and anthropometric principles, as they have to provide dynamic and active sitting during different lessons.
According to the results it can be concluded that design of school furniture must take into account the analysis of characteristic postures of pupils as one of the crucial
design criteria to be observed not only in two-dimensional but in three-dimensional system which implies a
study of the biomechanical movement of a pupil’s body.
The use of static 2D anthropometric measurements in
resolving dynamic 3D problems and exclusion of biomechanical parameters of human movements is not a
proper approach to design. Unfortunately, in the absence
of new findings, the basic starting points and guidelines
for chair and desk design are still international standards
and static anthropometry (3, 4, 32). They clearly recommend, even by sketches, that one should sit with a 90°
flexion of the hipjoint and a concavity in the small of the
back. As it has been seen in the research, no normal
young person is able to sit in this posture while working.
The standards are relevant guidelines and should be considered only as dimensional recommendations.
Present research confirms that to date static and rigid
design of school chairs and desks cannot be the support
to an active and restless young person of normal psychophysical growth and development. Also, the research
showed that regardless of the modern teaching process,
the school management could only choose conventionally designed furniture or the furniture that is financially
acceptable to the government due to the bureaucratic
system of procurement of equipment. Consequently, pupils use static and outdated chairs and desks.
Period biol, Vol 112, No 1, 2010.
Danijela Domljan et al.
Pupils’ working postures
The research on furniture influence on youths’ posture
has shown that, irrespective of its design, both the awareness of healthy sitting and the practices employed are of
equal importance and value. The point is in maintaining
the body dynamics over prolonged sitting. A child must be
given a wider choice of body positions. Ergonomically designed furniture that matches body proportions and size is
of great help in achieving this goal. Teaching about correct
sitting must start already during schooling, so that future
sitting issues in the office chair are minimized. Such approach as in this study – considering not only to consider
static body positions statistically evaluated but focusing on
quantitative and qualitative children working postures
and their sitting behavior, offers new criteria in school furniture design. Result of the application of the above-mentioned parameters in design process must be a product
that enables dynamic and active interaction with pupils,
which will ultimately lead to the final goal – the healthy
and comprehensive growth and development of young
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