ECO-Apparel vs. Other Leading
Sportswear Brands:
Physical Properties & Human Performance
Assessment
Prepared for Boardroom ECO-Apparel.
15/10/2009
1
Disclaimer: This work is for the internal use of Boardroom ECO Apparel, 1201 Franklin Street,
Vancouver BC V6A 1L2 (Boardroom). Boardroom is free to use any data/results obtained from
their own specific clothing items for any purpose, with the proper acknowledgement that the
work was performed by the Sport Innovation Centre at the Pacific Institute of Sport Excellence
(SPIN @ PISE). The use of the data/results from the other manufacturers is allowed as long as
the clothing articles are identified as High Performance Fabric “A” etc. and not by composition,
manufacturer or brand name.
2
EXECUTIVE SUMMARY
This report has been prepared for Boardroom ECO Apparel by the Sport Innovation Centre at the Pacific Institute
for Sport Excellence (SPIN @ PISE). The SPIN Centre is a partnership between Camosun College and the Canadian
Sport Centre Pacific (CSCP) and has capabilities to perform a wide range of fabric evaluations. This preliminary
investigation includes human performance testing and an initial evaluation of physical properties comparing four
currently available high performance garments with two Boardroom ECO products.
Six garments were tested. These were the ECO-Drytech, ECO-Stretch, Fabric A, Fabric B, Fabric C, and Fabric D. The
human performance element of testing involved the same subject cycling on an ergometer on 6 separate
o
o
occasions for 1 hour each time in a controlled environment (mean temp 25 C +/- 0.5 C, with mean humidity 64%
+/- 5%). Measures of heart rate, skin and core temperatures and psychophysical ratings (Rating of Perceived
Exertion (RPE), Thermal Comfort (TC), Thermal Sensation (TS) and Moisture Scale (MS) were recorded before,
during and after testing to provide physiological and perceptual responses of the subject for each garment. Body
weight and shirt weight was also measured pre and post exercise to estimate specific sweating rates and moisture
regain of the garments.
The human performance testing found small differences in physiological strain between the six shirts under the
conditions tested. The slightly greater thermal and cardiovascular strain observed while wearing Fabric B and
Fabric C is confounded by the fact that these shirts had a tighter fit than the other 3 shirts. Therefore it is difficult
to attribute the differences that were observed, to the fabric properties or to the fit of the garment. Nevertheless
Fabric A and the two ECO shirts performed better than the other garments in the environment tested.
The physical properties of the garment fabrics were tested using a Sweating Guarded Hotplate with testing taking
place in a controlled environment (~25°C; rH ~65%; wind velocity ~1m/s). Each sample was washed once before
undergoing 3 dry and 3 wet tests, after which an average for each measure was obtained.
Results for the physical properties section of testing followed a similar trend to those observed in the human
performance testing. The ECO-Drytech and Fabric A were the best performers with both low thermal and
evaporative resistance scores compared to the other samples. The ECO-Stretch came next, followed by Fabric B
and Fabric D. Fabric C performed worst in the testing with resistance values noticeably higher than the nearest
fabric.
With regards to the Boardroom ECO-Apparel, the physical properties testing showed that these fabrics performed
well compared to the other garment fabrics tested. The ECO-Drytech was highly comparable to Fabric A and so
would be most suitable if worn when keeping cool is the priority. Although the ECO-Stretch did not perform as well
as some of the other fabrics it would still be useful as a removable layer to help optimise thermal management.
With both elements of testing it is important to note that the performance evaluation would look quite different if
the environmental conditions used for testing were changed.
3
INTRODUCTION
This report has been prepared for Boardroom ECO Apparel by the Sport Innovation Centre at the Pacific Institute
for Sport Excellence (SPIN @ PISE). The SPIN Centre is a partnership between Camosun College and the Canadian
Sport Centre Pacific (CSCP) and has capabilities to perform a wide range of fabric evaluations. This preliminary
investigation includes human performance testing and an initial evaluation of physical properties comparing four
currently available high performance garments with two Boardroom ECO products.
HUMAN PERFORMANCE TESTING
Methods
Preliminary work to quantify thermal and physiological strain while wearing six different shirts in a warm
environment was conducted during the month of September 2009. One subject (female160.0cm, 48.0 kg) rode for
o
o
six, 1 hour sessions in a controlled environmental chamber (mean temp 25 C +/- 0.5 C, with mean humidity 64%
+/- 5%). All sessions were conducted mid- morning with a minimum of 48 hours between sessions.
Garments
The six shirts tested:
COMPOSITION
FIT
MASS
ECO-DRYTECH
50% recycled polyester/ 50% eco-carbon
Loose
140g
ECO-STRETCH
63% nylon/ 23% eco-carbon/ 14% lycra
Loose
280g
FABRIC A
100% polyester
Loose
160g
FABRIC B
92% polyester/ 8% spandex
Tight
220g
FABRIC C
65% Nylon/ 21% polyester/ 14% elastane
Tight
140g
FABRIC D
100% Cotton
Tight
120g
All six shirts were designed for use during the fall/winter months (possibly worn on their own or under a jacket),
with long sleeves and high collars.
Pre-Test Procedures
Upon arrival to the lab, the following variables were measured:
-
A urine sample was provided to determine hydration status using urine specific gravity measured
with a digital refractometer.
Pre-exercise body weight was measured to 0.01 kg
Exercise and Thermal Stress
o
o
The subject exercised in a controlled environmental chamber (25 C +/- 0.5 C and 64% +/- 5% relative humidity).
These conditions were chosen to impose a moderate thermal load that was consistent with the weather conditions
that athletes would wear the test garments in. Ambient conditions were recorded every ten minutes.
4
A Velotron cycle ergometer was set to ensure power output was constant at 100W through a 60 minute exercise
period. Cycling data (speed, power, and RPM) was logged continuously and the subject maintained a consistent
cadence throughout each session (100rpm +/- 2 rpm).
Measurement of Physiological Strain
Rectal probes were used to monitor core temperature (Tr), and skin thermistors taped to the bicep (Tb), chest
(Tch), thigh (Tt) and calf (Tc) measured upper and lower body temperatures. Heart rate (HR) was measured using a
Polar HR monitor. Total Physiological Strain was represented by the Physiological Strain Index (PSI) calculated as:
-1
-1
PSI = 5(Tret – Tre0) x (39.5 – T re0) + 5(HRt – HR0) X (180 – HR0)
-
RE = rectal temperature
Tret & HRt = simultaneous measurements taken at fixed time points during exercise
Tre0 & HR0 = baseline measures
o
Limits = 36.5 < Tre < 39.5 C and 60 < HR < 180 bpm
Once the subjects were instrumented, baseline measures of HR, skin and core temperatures and psychophysical
ratings - Rating of Perceived Exertion (RPE), Thermal Comfort (TC), Thermal Sensation (TS) and Moisture Scale (MS)
were recorded (Scales provided in Appendix). Prior to initiation of the 60 min of cycling, another set of baseline
measures were recorded. HR, Tr, skin temperatures and psychophysical rating were recorded every 10 minutes
from time 0 to 60 minutes. Post test measures of body weight (subject towelled off and put on dry clothing), fluid
consumption (which was controlled at approx 0.35L) and shirt weight were recorded. Note that the shirt was
weighed immediately before any significant evaporation or drying could occur.
5
Physiological Results
General Level of Strain
A summary of the subjects’ physiological responses during each garment test is provided in table 1. In general the
subject was exercising at a moderate exercise intensity based upon the comprehensive measures of physiological
o
o
strain. Core temperature was elevated between 0.8 to 1.7 C and reached a maximum of 38.3 C, far from the
tolerable limit. HR also reached maximum rates of 145 to 154 bpm, approximately 85-90% of age predicted
maximum heart rate for the subject. The Physiological Strain Index, which incorporates both cardiovascular and
thermal indices of strain also ranged from 5.1 to 6.7, well below the maximum on this ten point scale. Sweat rates
were also moderate and in the range expected for a fit female exercising in a moderately warm environment.
When comparing the physiological response of the subject across the six test garments it is clear that some
garments outperformed others as evident by the lower levels of physiological strain experienced during an
identical stress test.
Cardiovascular Strain
There was a 10 beat range in mean HR and 9 beat range in final HR for the female subject over the 6 conditions
with the highest mean and final HR’s observed while the subject was wearing Fabric C and D. Lowest values in both
mean and final HR were observed while exercising wearing Fabric A and both ECO shirts (ECO-Drytech and ECOStretch).
Thermal Strain
The same trend was observed in the body temperature response, with the largest increases observed while
wearing Fabric’s B, C and D, and the lowest changes occurring while the subject exercised in Fabric A and ECO
products.
Overall Response
As the Physiological Strain Index reflects both the cardiovascular and thermal strain, it is not surprising that the
trend remains consistent with Fabric B, C and D producing the greatest degree of Physiological strain and Fabric A
and both of the ECO garments inducing the lowest cumulative physiological strain. In summary Fabric’s B, C and D
resulted in a greater thermal load to the subject, whereas the subject was cooler while riding in Fabric A & ECO
shirts.
It should be noted that the fit of the shirts was quite different with Fabric A and ECO shirts being much looser on
the subject, while Fabric B and C were very snug. The looser shirts allowed for greater air flow between the body
and the shirt (bellows effect), which may facilitate greater convective and evaporative cooling from the skin
surface.
6
Table 1. The physiological response of a female subject during 1 hour of cycling while wearing different performance shirts in
a moderately warm environment.
RECTAL TEMPERATURE
mean
o
Final
o
change
o
BODY TEMPERATURE
mean
o
final
o
HEART RATE
mean
final
PHYSIOLOGICAL
SWEAT
STRAIN INDEX
RATE
mean
final
(L/hr)
( C)
( C)
( C)
( C)
( C)
(bpm)
(bpm)
ECO-DRYTECH
37.8
38.0
0.9
36.8
37.0
130
147
4.2
5.3
0.78
ECO-STRETCH
37.5
38.0
0.9
36.8
37.2
130
146
3.7
5.4
0.98
FABRIC A
37.8
37.9
0.8
36.7
36.7
126
145
3.9
5.1
0.80
FABRIC B
38.0
38.3
1.2
37.1
37.4
134
150
4.0
6.1
0.86
FABRIC C
37.8
38.2
1.2
37.3
37.7
136
154
4.8
6.3
0.96
FABRIC D
37.7
38.2
1.7
36.8
37.3
136
153
5.0
6.7
0.89
Table 1 also presents calculated sweat rates which were relatively consistent for the 6 trials with a range of 0.78 –
0.98 L/hr and little difference between test garments. Moisture collected in the shirts (Table 2) ranged from 800
to 140 g with Fabric A and ECO shirts retaining the least amount of moisture and Fabric D retaining the most.
Table 2. Weight of the shirts pre and post cycle.
PRE WEIGHT (g)
POST WEIGHT (g)
DIFFERENCE (g)
ECO-DRYTECH
140
220
80
ECO-STRETCH
280
360
80
FABRIC A
160
180
20
FABRIC B
220
320
100
FABRIC C
140
260
120
FABRIC D
120
260
140
7
Perceptual Response
The perceptual response of the subjects while wearing the different garments was quite consistent (Table 3). In
general the subjects felt slightly warm to warm at the end of each trial and slightly uncomfortable to
uncomfortable with their body temperature. The greater thermal physiological strain seen with Fabric’s B, C and D
did not translate to markedly greater levels of thermal discomfort. As expected and because of the constant work
rate (100 W) the subjects rating of perceived exertion varied little between tests. Finally, the subject felt slightly
drier on average wearing Fabric C compared to the other products.
Table 3. Perceptual response of a female subject during 1 hour of cycling while wearing different performance shirts in a
moderately warm environment
THERMAL SENSATION
THERMAL COMFORT
PERCEIVED EXERTION
MOISTURE RATING
mean
final
mean
final
mean
final
mean
final
ECO-DRYTECH
6.64
7.0
2.29
3.0
11.79
13.0
4.71
3.0
ECO-STRETCH
6.36
6.0
2.57
3.0
11.86
13.0
4.50
3.0
FABRIC A
6.57
7.0
2.21
2.5
11.79
13.0
4.93
3.0
FABRIC B
6.79
7.0
2.57
3.0
11.79
13.0
4.29
3.0
FABRIC C
6.71
7.0
2.57
3.0
12.14
13.5
5.36
4.0
FABRIC D
6.43
7.0
2.43
3.5
11.86
13.0
4.71
3.0
Thermal Sensation Scale 0 = unbearably cold to 9 = very hot
Thermal Comfort Scale 1 = comfortable to 5 = extremely uncomfortable
Rating of Perceived Exertion 6 = No exertion to 20 = maximal exertion
Moisture Scale 9 = very dry to 1 = very wet
Summary
There was a small difference in physiological strain experienced by the subject when wearing the six shirts under
the conditions tested. The slightly greater thermal and cardiovascular strain observed while wearing the Fabric B
and D is confounded by the fact that these shirts had a tighter fit than the other 3 shirts. Therefore it is difficult to
attribute the differences that were observed, to the fabric properties or to the fit of the garment. Nevertheless
Fabric A and the two ECO shirts performed better than the other garments in the conditions tested. It is important
to note that the performance evaluation would look quite different if the weather conditions tested were colder.
Thus the data presented is specific to the conditions utilised in this experiment and to the female subject.
8
PHYSICAL PROPERTIES
Testing Procedure
Fabric samples were tested using a Sweating Guarded Hotplate in an environmental chamber set at ~25°C, rH
~65%, and wind velocity ~1m/s. Each sample was washed once before undergoing 3 dry and 3 wet tests, after
which an average for each parameter in each fabric was obtained.
Description of Physical Parameters
Thermal Resistance
Thermal Resistance is defined as the total resistance of the fabric to dry heat loss from the body surface. It is a
measure of what is more commonly referred to as ‘thermal insulation’. It includes the resistance provided by the
fabric and also the air layer between the fabric and body surface.
Ideal thermal insulation values differ for dissimilar climatic conditions. A high resistance value means a fabric has
better thermal insulating properties. Therefore, with higher resistance, heat is not able to escape as readily as it
would in a material with low thermal resistance. Consequently, fabrics with higher thermal insulation scores are
more appropriate for cold weather conditions as opposed to those with the lower values that are ideal for the
warmer climates.
The thermal resistance of a fabric is a valuable measure for determining which fabric to wear in which
environment. However it is by no means the only measure that need be considered. The most important
mechanism for the dissipation of heat during exercise is evaporation. All clothing provides a barrier to evaporative
heat transfer, but some fabrics provide more of an obstruction than others. This is why the Evaporative Resistance
of a fabric is important.
Evaporative Resistance
The Evaporative Resistance of a fabric indicates the resistance to evaporative heat transfer provided by the fabric
and the boundary air layer under the material. Evaporative heat transfer is the most important means for
dissipating heat during physical activity. If evaporation is prevented then sweat begins to pool on the body surface.
This pooling does not contribute to heat dissipation. Consequently evaporative resistance is a crucial component of
performance apparel fabrics.
The evaporative resistance is a measure of what is more often termed the ‘breathability’ of a fabric. A higher
evaporative resistance score would indicate a greater barrier to the movement of water vapour away from the
body surface than a fabric with a lower resistance. Therefore the lower the evaporative resistance, the more
‘breathable’ a fabric is, thus the more effective at keeping the individual cool and dry. As a result sports apparel
fabrics should have as low an evaporative resistance as possible for all climatic conditions.
Although both the aforementioned values are of great importance in sport and lifestyle apparel, difficulties do
arise when an individual wishes to identify an optimum fabric. Fabrics obviously vary in both insulation and
evaporative heat properties; one, for example, could have a more appropriate thermal resistance for activity in hot
weather than another that has better breathability. How can you choose between the two? This is where the
Moisture Permeability Index can be applied.
9
Moisture Permeability Index
The Moisture Permeability Index indicates the maximum evaporative heat transfer permitted by a fabric
compared to an ideal maximum for an uncovered surface (i.e. a nude body). It does this by calculating a score for a
fabric between 0 (completely impermeable) and 1 (fully permeable) using both their individual thermal resistance
and evaporative resistance values to produce an accurate representation of the material’s respective properties.
Consequently the higher the fabric’s permeability index, the greater the moisture permeability of the fabric
relative to its insulation level. Therefore a higher moisture permeability index is better for both thermal comfort
and evaporative heat transfer in the heat. However careful consideration of this value is important when
deliberating its use in a colder environment as a lower value is not necessarily the ideal. A lower value would
indicate higher evaporative resistance and as a result may increase discomfort due to reduced sweat evaporation.
It is therefore necessary to also consider all three measures before deeming which fabric is most favourable.
10
Physical Properties Results
Table 4. The Thermal Resistance, Evaporative Resistance and Moisture Permeability Index of tested fabrics.
THERMAL RESISTANCE
2
EVAPORATIVE
RESISTANCE
-1
(m ·°C·W )
2
MOISTURE
PERMEABILITY INDEX
-1
(m ·kPa·W )
Fabric B
92% Polyester/8% Elastane
Fabric C
65% Nylon/21% Polyester/ 14% Elastane
Fabric D
0.63
0.014
2.55
0.69
0.028
4.90
0.60
0.034
7.69
0.49
0.020
3.70
0.58
9
0.035
8
0.03
0.005
0
Fabric A
0.01
ECO-Stretch
0.015
Fabric D
Fabric B
0.02
Fabric C
0.025
Fabric
Figure 1. Thermal Resistance.
Evaporative Resistance (m2·kPa·W-1)
0.04
ECO-Drytech
Thermal Resistance (m2·°C·W-1)
100% Cotton
3.31
7
6
5
4
3
2
1
0
Fabric D
100% Polyester
0.015
Fabric C
Fabric A
0.68
Fabric B
63% Nylon/23% Eco Carbon/ 14% Lycra
2.11
Fabric A
ECO-Stretch
0.012
ECO-Stretch
50% Recycled Polyester/50% Eco- Carbon
ECO-Drytech
ECO-Drytech
Fabric
Figure 2. Evaporative Resistance.
Figure 1 illustrates the range of thermal resistance values between garments. The ECO-Drytech ensemble showed
the best thermal resistance for the environment in which testing took place (~25°C, rH: 65). At this temperature
and humidity a lower resistance value is preferred as this means a fabric can dissipate heat more readily than
those with a higher resistance. Fabric A was the next best performing material with the ECO-Stretch following
closely behind. Fabric D score lay around halfway between the first three fabric garments and the last two.
Understandably Fabric B and C performed worst. These garments are expected to be worn in colder environments
than they were tested in for this investigation. The thermal resistance of a fabric is often influenced by the fabric
thickness. Under simple scrutiny it is easy to see that Fabric A and ECO-Drytech are considerably thinner than
Fabric B and C.
11
Fabric D
Fabric C
Fabric B
Fabric A
ECO-Stretch
ECO-Drytech
0
0.2
0.4
0.6
0.8
1
Figure 2 shows the evaporative
resistance of the tested fabrics.
These results follow a similar
pattern to the thermal resistance
with the ECO-Drytech performing
better than the other fabrics and
Fabric C performing worst. The
difference between fabric values is
however more striking, with the
evaporative resistance for the
ECO-Drytech almost half that of
Fabric C.
The final area of investigation was
the Moisture Permeability Index
depicted in Figure 3. For use in the environment in which the fabrics were tested, as high as possible moisture
permeability index is advisable. Therefore you can see that the ECO-Drytech and Fabric A again performed best.
Interestingly, however, Fabric A achieved a slightly better score than the ECO-Drytech. This is due to the relative
difference between the two fabrics thermal and evaporative resistance measures, meaning that for Fabric A’s
higher thermal resistance the relatively lower evaporative resistance observed equated to a higher moisture
permeability index value.
Figure3. Moisture Permeability Index
Also included in the attached Appendices are micrograph comparisons of all the fabrics tested as well as an
example of a thermal imaging test. In addition, the SPIN Centre has the capability to also measure other physical
properties including mechanical strength of fibres and fabrics. This unique combination of human performance
analysis coupled with a comprehensive suite of material evaluation tests would be ideal for a longer term set of
fabric evaluation tests.
In conclusion, both fabric’s used in the ECO-Drytech and ECO-Stretch compared well to the other performance
apparel materials tested.
Table 5. Physical Parameters Summary for ECO-Drytech & ECO-Stretch
THERMAL
RESISTANCE
ECO-Drytech
ECO-Stretch
EVAPORATIVE
RESISTANCE
MOISTURE PERMEABILITY
INDEX
SUGGESTED ENVIRONMENT
Warm-Hot
0.068
6.11
0.68
The fabric performed well in the tested environment. It was highly comparable to Fabric A in each test and
so would be most suitable worn when keeping cool is the priority.
Cold-Cool
0.075
7.31
0.63
(with additional layer
underneath)
The fabric performed satisfactorily compared to the other fabrics tested. This garment is not designed as a
base layer like the other fabrics. Therefore it would be highly useful as a removable layer assisting with
optimal thermoregulation.
12
Appendix
13
THERMAL SENSATION
0
UNBEARABLY COLD
0.5
1
VERY COLD
1.5
2
COLD
2.5
3
SOMEWHAT COLD
3.5
4
COMFORTABLE
4.5
5
SOMEWHAT HOT
5.5
6
HOT
6.5
7
VERY HOT
7.5
8
UNBEARABLY HOT
14
THERMAL COMFORT
1
COMFORTABLE
1.5
2
SLIGHTLY UNCOMFORTABLE
2.5
3
UNCOMFORTABLE
3.5
4
VERY UNCOMFORTABLE
4.5
5
EXTREMELY UNCOMFORTABLE
(GAGGE ET AL., 1067)
CUE: “HOW COMFORTABL ARE YOU?”
15
0
MOISTURE SCALE
UNBEARABLY DRENCHED
0.5
1
DRENCHED
1.5
2
VERY WET
2.5
3
WET
3.5
4
SOMEWHAT WET
4.5
5
DAMP
5.5
6
SOMEWHAT DAMP
6.5
7
COMFORTABLE
7.5
8
SOMEWHAT DRY
16
RATING OF PERCEIVED EXERTION
6
NO EXERTION AT ALL
7
EXTREMELY LIGHT
8
9
VERY LIGHT
10
11
LIGHT
12
13
SOMEWHAT HARD
14
15
HARD (HEAVY)
16
17
VERY HARD
18
19
EXTREMELY HARD
20
MAXIMAL EXERTION
RPE IS A MEASURE OF HOW HARD THE ATHLETE THINKS THEY ARE WORKING. THAT IS, THE TOTAL AMOUNT EXERTION AND
PHYSICAL FATIGUE, COMBINING ALL SENSATIONS AND FEELINGS OF PHYSICAL STRESS AND EFFORT
CUE: “HOW HARD DID YOU WORK?”
17
18
19
20
21
22
23
24
25
26
27