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IMPLICATIONS OF DYNAMIC WORKING POSTURES IN
GARMENTS’ COMFORT
Sara Bragança1, Pedro Arezes1, Miguel Carvalho1, Susan Ashdown2
1 University of Minho, Guimaraes, PORTUGAL, saraabraganca@gmail.com;
parezes@dps.uminho.pt; migcar@det.uminho.pt
2 Cornell University, Ithaca, NY, USA, spa4@cornell.edu
Abstract
Most work and leisure activities imply the adoption of many dynamic postures, such as stretching
the arms foreword or upwards. Some of these postures can be restricted or obstructed by the
clothes people wear, as they may be too tight or too loose, limiting/obstructing the range of
movements. In this paper, it will be presented a preliminary study to support the development of a
prototype of a flexible garment that can be adapted to several dynamic postures. For this study,
two female body basic patterns were created: one with the regular static body measurements and
the other with the body measurements in a dynamic posture. These models were compared using
5 compression sensors that were used to evaluate the compression forces exerted on the
participants’ body. With this study, it was possible to conclude that clothes that are not designed
taking in consideration the dynamic postures greatly affect the users’ felling of comfort and
performance.
Keywords: dynamic postures, range of movements, comfort, clothing
1. INTRODUCTION
The shape and size of the human body changes according to the posture adopted. Most
of these modifications that occur on the body can become uncomfortable for people
adopting prolonged postures, such as workers, especially when the clothes they wear are
not adequate and cannot be adapted to the challenges of the tasks to be performed. As
such, some of the negative issues can be attenuated when wearing appropriate clothing,
preventing health issues and increasing perceived comfort.
However, some discomfort in clothing can be felt with movement or when dynamic
postures are assumed. When the body moves the dimensions change, for example the
increase of the length on one side of a bending joint and the decrease of the length on
the other side [1]. If the clothing does not increase in dimension over a bending joint, or
binds where body dimensions decrease, it will restrict movement or intensify its
difficulty creating discomfort.
User-cantered design approaches, where ergonomic principles and anthropometrics are
considered, should be preferred when creating new products as they aim to minimize the
stress imposed to the users [2]. Tichauer [3] stated that considerable impacts on
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workers’ productivity and occupational health and safety can be obtained with small
changes to the items people interact with.
According to Cichocka et al. [4] developing a garment may be one of the most difficult
problems in the field of textile engineering, and consequently, before designing a
garment adapted to the human body, it is imperative to have an intimate knowledge of
its morphology in order to meet the final style successfully. In the study of Imaoka and
Atkinson [5], three models of representation to perform the simulation of garment
design were presented (garment model, human body model and the environment model)
– leading to the development of the human-clothing environment concept. In more
recent years, Gupta et al. [6] defined the fundamental requirements of clothing as being
the following: (i) ability to protect users from the external environment (heat, cold, wind
and rain); (ii) capacity to maintain the internal microenvironment, allowing heat and
moisture transport throughout the body; (iii) facility to exert minimal inhibition,
allowing free range of movement and the accomplishment of desired tasks; and (iv)
simplicity of use, specially regarding the donning and doffing of the garments.
Clothes are designed to fit people within a range of dimensions and general body types.
However, clothing size and fit are concepts very difficult to quantify and analyse
because the relationship between the human body and the clothing is complex and often
ambiguous [7]. As such, the understanding of the relationship between garments and the
human body implies the need to analyse many complex factors.
Ideally, clothing must have sufficient ease or enough elasticity, but not being too loose
or too tight, allowing the worker to move uninhibited and to be comfortable [8]. In any
of those cases, the wearer’s mobility and the level of protection provided by the garment
can be adversely affected [9].
A person with an active lifestyle is further at risk for fit challenges when sitting at work,
driving, travelling, walking, bending, and riding a bike or a horse. The human body
shape and size changes with motion, but the clothing worn is not designed to adapt to
these dynamic postures [10]. Usually, what fits when people are in a static posture does
not fit when they are in a dynamic posture, creating in some circumstances not just
discomfort but even damage.
The purpose of this paper is to present a preliminary study that was conducted in order
to develop a prototype of a flexible garment that can be adapted to several dynamic
postures.
2. MATERIALS AND METHODS
Fifty participants volunteered to take part in this study, 12 of them were females and 38
were males. This sample had an average age of 36.49 ± 11.39 years old, an average
height of 170.86 ± 6.93 cm and an average height of 71.30 ± 10.70 kg.
These participants worked in four different companies/institutions – one research centre,
one software development company, one industrial company and one university. A
formal contact was established with the companies, inviting them to participate in the
study.
The participation in this study was voluntary and participants were selected by the
management board of the company. When contacted, the participants were informed of
the detailed procedures and requirements of the test.
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After gathering all the necessary information, through questionnaires and
anthropometric measurements, the development of a prototype was done in partnership
with a specialized company – Weadapt – Inclusive Design and Engineering Solutions.
To create a base model that was form-fitting it was necessary to select the body
measurements of a particular person, who was supposed to try on the prototypes and in
whom all the tests were performed. The development of the prototypes started with the
design of two base patterns for the women’s upper body, using the ESMOD
methodology [11].
For the first base model the measurements considered were those collected with the
participant in position a static standing position (here on addressed as P1), while for the
second base model, the measurements considered corresponded to a dynamic position
(here on addressed as P3).
The two base models were constructed with a non-elastic woven fabric, fitting the
garment as close to the skin as possible. The selected woven fabric can be characterized
as a plain fabric with a composition of 43% cotton and 57% polyester.
To compare the two base models, five compression sensors were attached to the fabric
with pins (
Figure 1). These sensors were physically connected to a device, which then transmitted
recorded data via Bluetooth to a tablet.
The selection of the parts of the body where the sensors were placed was based on a
previous test that revealed the areas more sensitive to tears when the participant moved
from P1 to P3.
Figure 1: Compression sensors on the base models and their location on the body.
After correctly placing the sensors, the test was performed for both base model and for
all the postures. In this compression forces test another posture was added, a variation
of P3, identified here on as P3v. This posture was an exaggeration of P3, where the
participant crossed his/her arms in the front, increasing even more the compression
forces in some areas.
Most of the tasks performed by people at work only require them to lift their arms to the
front. However, this additional posture was important to consider because it allowed
understanding the impact of the amplification of the forces to the absolute maximum.
Figure 2 shows the postures made by the participant for this test.
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Figure 2: Participant in the several postures for Test 2 (P1, P3, P3v from left to right).
The test was developed as follows: the participant put on the first base model; the values
of compression were recorded in P1, then participant switched to P3 and the values
were recorded again and finally the participant switched to P3v and the values were also
recorded. This process was repeated three times, totalling nine records.
The participant then donned the second base model with identically placed sensors, and
took the three positions again to collect data for comparison. This process was also
repeated three times, totalling nine more records.
The purpose of this test was to compare the compression forces present when a garment
is designed taking in consideration only the static measurements (static base model) and
those present when a garment is designed taking in consideration measurements in a
dynamic position (dynamic base model).
Another goal was to quantify the percentage of increase in compression forces when
people switch from a static standing posture to a more dynamic posture.
The mean of the three observations was calculated, as well as the variation that occurred
between P1 and P3 and P1 and P3v in each base model and between the two base
models when in the dynamic posture P3. These comparisons were analysed in terms of
increase and/or decrease (in percentage) of the compression forces in the various
predefined body locations
3. RESULTS AND DISCUSSION
The two base models constructed in the non-elastic woven fabric are presented in
Figure 3. As can be seen, both models are skin-tight. However, in the dynamic model
there is some slack in the upper back area due to the alteration in the back pattern to
accommodate the P3 dimensions.
Nevertheless, to the naked eye and in the opinions of the authors, the dynamic version is
not very pleasing in terms of fit and aesthetics, as in a static position there is an excess
of material close to the armhole, thus the need to develop more satisfying prototypes.
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Static model
Dynamic model
Figure 3: Static and dynamic base models in fabric.
The test with the compression sensors demonstrated that there was a much higher
increase in compression forces when changing from P1 to P3 and from P1 to P3v in the
static model. Figure 4 shows the results of the mean of the three repetitions made in this
test for each of the base models.
As expected, the compression increases very much when the arms are raised. The only
exception occurred for sensor 1 that decreases, because when the arms are to the front
the garment becomes looser in that upper area, reducing the contact between the fabric
and skin.
Comparing P3 to P3v, it can be seen that this exaggeration in the posture has, in fact, a
meaningful impact on the compression forces. The values recorded by all the sensors
are higher in P3v than in P3. Still, as it happened with P3, in P3v the dynamic base
model also showed better results.
When comparing the compression forces in P3 and in P3v in the two base models, it
was concluded that all sensors presented a much smaller value when the participant was
wearing the dynamic base model.
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Figure 4: Mean increase of the compression forces when changing from P1 to P3 (up)
and from P1 to P3v (down) for both base models.
Table 1 presents the compression forces values for each sensor in P3 and P3v. It noted
that when in P3v the compression forces are higher than when in P3, for both base
models and for every sensor. Figure 5 summarizes the improvements obtained for each
sensor when changing from the static base model to the dynamic base model with the
participant in P3. The results for P3v are very similar and as such not necessary to
demonstrate.
Table 1: Values of the compression forces in each sensor (in Pa).
Sensor
Static model
in P3
Dynamic model
in P3
Static model
in P3v
Dynamic
model
in P3v
1
160
23
387
53
2
5676
3070
6950
4333
3
5062
1644
5466
1680
4
2240
1240
3356
3196
5
196
156
244
249
-3000
-1000
1000
3000
5000
7000
1 2 3 4 5
Increase in compression forces
from P1 to P3 (in Pa)
Compression sensor
Static base model
Dynamic base model
-2000
0
2000
4000
6000
8000
1 2 3 4 5
Increase in compression forces
from P1 to P3v (in Pa)
Compression sensor
Static base model
Dynamic base model
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Figure 5: Improvement in terms of compression forces when in P3 from the static base
model to the dynamic base model.
The static base model was so tight that the participant could barely raise their arms.
Despite the fact that movement was made easier in the dynamic base model, it is
important to note that this base model continues to be very form-fitting in the torso and
arms. The only difference was that more space to accommodate the across back length
increase was created.
Nevertheless, the results obtained show a very significant improvement from the static
base model, with the minimum decrease in compression forces being 21%.
4. CONCLUSIONS
The compression forces tests clearly showed that the fact that clothes that are not
designed taking in consideration the dynamic postures affect in great part the
compression imposed to the user, limiting his/her movements and causing him/her
discomfort.
It is understandable that fashion designers want to create models that fit the wearer
perfectly. However, people’s daily routines include much more dynamic postures than
those performed on the catwalk. Everyday activities force people to changes postures
rapidly, to sit and to stand, to put the arms in the air and so many other awkward
postures. Nonetheless, with the results presented here it is possible to identify and to
quantify some alterations that should be taken in consideration in the garments’ design
process.
Only when taking in consideration the variations that occur in the body with the several
dynamic postures adopted during the day, it will be possible to create functional clothes
that can adjust to people’s daily activities and needs. These adjustments are fundamental
to ensure the freedom of movements and users comfort, aspects that are so important
when engaging in both labour and leisure activities. These characteristics, allied to a
good looking and fashionable design, would surely make the people who value comfort
and aesthetics much more satisfied.
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ACKNOWLEDGMENTS
This work is financed by FEDER funds through the Competitive Factors Operational
Program (COMPETE) POCI-01-0145-FEDER-007043 and by national funds through
FCT - Portuguese Foundation for Science and Technology, under the projects
UID/CEC/00319/2013 and UID/CTM/000264.
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