22 Sensory comfort of aerobic wear ANTHONY S.W. WO NG 1 AND YI LI 2 School of Nursing, The Hong Kong Polytechnic University, Hong Kong 2 Institute of Textiles and Clothing, The Hong Kong Polytechnic University, Hong Kong 1
Sportswear requires aesthetic features such as an attractive appearance and a pleasant look as well as functions that improve athletes’ performance, provide extra comfort and promote the health of the wearer.9 Today’s garments for sports and active outdoor wear are lighter, softer, more durable and faster drying. Also, they perform a multitude of functions while appealing to the fashion-conscious consumer.8 In the study of trends in sports and other performance apparel markets, Muran8 pointed out the following. 1. Women tend to spend more on performance apparel than men. 2. There is a tendency for fashion and function to merge in the industry. 3. Technological developments have led to the creation of intelligent, stimuli-sensitive fabrics for the activewear and casual wear markets – a broad range of intelligent fabrics, some of which interact with the body to provide health benefits, has hit the market. 4. Research and development will continue to take center stage as companies search for new ways to gain a competitive advantage by providing peak performance and more comfort. Factors such as (1) increased sports participation, (2) specialty clothing, (3) increased performance requirements, (4) fitness and sports dressing related to self-image and lifestyle, (5) greater consumer demand and (6) innovative materials have had a significant influence on the growth of the sportswear market since the 1980s.6 Shiotani and Hayakawa9 listed the properties, including thermal insulation, moisture-permeable waterproof properties, water repellency, ultraviolet ray shielding performance, moisture absorption, perspiration absorption, quick dryability, anti-bacterial deodorizing properties and stretchability, that should be considered in sportswear. Chaudhari2 pointed out that the desirable attributes of functional sportswear include optimum moisture and heat regulation, good water and air permeability, absence of dampness and soft and pleasant touch. 366
Sensory comfort of aerobic wear
Much research has been carried out in relation to active sportswear and its relation with the human body. Bardhan and Sule1 discussed the logic and anatomy of comfortable, functional sportswear with stretch ratios. Susnik and Zadnikar10 investigated the thermoregulation of aerobic dancers dressed in tracksuits made of cotton and Lycra fabrics. In their study, six female aerobic dancers were asked to wear tracksuits made from 100% cotton and 100% Lycra during a vigorous 45 minutes’ workout wear trial, in which relative humidity, air temperature and air speed were kept constant. Results showed that the mean body temperature of the dancers wearing the Lycra tracksuits was slightly lower than that of the dancers wearing cotton tracksuits at the end of the workout. Only one dancer felt comfortable in both types of tracksuit. Subjective evaluation of how much perspiration was generated was about the same for both fabrics. Dickson and Pollack3 studied the needs and preferences of 54 female in-line skaters, as consumer athletes, in Ohio and Florida, regarding their skating commitment, sport clothing interests and preferences and skating behaviors. The results showed that greater interest in achieving a unique and feminine appearance for performance enhancement and greater desire for fashion rather than comfort significantly predicted female skaters’ likelihood of buying clothing specifically for in-line skating. Additionally, a model was developed to predict the likelihood of purchasing special skating clothing on the basis of a skater’s age and commitment to skating. Feather et al.4 investigated if there were differences between black and white female athletes’ satisfaction with their bodies and fit of their clothing in order to examine the relationship between body satisfaction and clothing fit. A total of 290 female collegiate basketball players (168 white and 122 black) participated in this study. Their evaluations on body satisfaction and clothing fit were analyzed using MANOVA, Hotelling’s Tsup 2, ANOVAs and Pearson Product Moment correlations. The results showed that black females were more positive about their bodies than white females in terms of perception of their overall bodies. However, there was no significant difference in satisfaction with garment fit between athletes. Significant positive correlations were found between perceptions of body cathexis and garment fit. The relationships between active sportswear and human physiological responses have been studied. For example, the effect of sportswear from three experimental knitted fabrics and two types of environmental conditions on the stratum corneum water content, rate of water evaporation from the skin surface, rate of capillary blood flow and skin temperature on seven fit female subjects was studied by Markee et al.7 In their study, each subject was required to wear garments from 1.5 den polyester, 3.5 den polyester or 100% combed cotton while exercising and resting in a hot/humid and a hot/dry environment. Their findings include the following.
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1. Rate of evaporative water loss was slower at high humidities, when more water also accumulated in the stratum corneum during exercise. 2. Capillary blood flow is not significantly affected by environment and the difference in skin temperature is negligible. 3. With loose-fitting garments for hot environments, greater consideration should be given to openness of construction rather than to fibre content; when the fit is snug, fibre content may be of more critical importance in maintaining comfort. Wang et al.11 conducted a survey on student athletes’ psychological and physiological evaluations of sportswear in Taiwan. Survey results indicated subjects agreed that sportswear has an important effect on their performance. A series of properties related to sportswear were considered. Subjects found ease, moisture sorption, softness, air permeability and elasticity to be important properties in sportswear, and other properties such as color, brand, appearance and price were considered as relatively unimportant. However, the subjects ranked both appearance and price as significantly more important when the survey changed the type of question to a priority order. The responses on priorities between male and female athletes were completely different. Males ranked appearance, color and brand as priorities, whereas females ranked durability, ease, softness and moisture sorption as priorities. The most important sources of discomfort were caused by perspiration on the skin because of poor moisture sorption, restriction of movement and abrasion. The males were more sensitive to discomfort than the females. Harumi et al.5 clarified the effects of the clothing pressure exerted on a trunk by a swimsuit on heart rate, skin blood flow and respiratory function, by conducting wear tests on seven female students. They found that, when a swimsuit was worn, blood pressure increased and heart rate decreased in a standing posture. Furthermore, oxygen intake and ventilation decreased during exercise. Based on these results, they concluded that, when the clothing pressure exerted on a trunk was relatively low – lower than 1.0 kPa – venous pump action was promoted and work efficiency became higher. However, when the clothing pressure exerted on a shoulder and inguinal region was very high, skin blood flow to peripheral parts (foot) was suppressed and the recovery of blood pressure after exercise was delayed. In order to investigate the relationship between clothing pressure comfort and tight-fit active sportswear, Zhang et al.13 developed a mechanical model for numerical simulations of 3D dynamic garment pressure during wear using a finite element method. Based on analyzing the contact characteristics between the human body and the garment, a mechanical model was developed using the theory of dynamic contact mechanics. A process of a female human model wearing a set of perfectly fitting sportswear, with the
Sensory comfort of aerobic wear
same style and made of either cotton denim or knitted nylon fabrics, was simulated. The garment was regarded as an elastic shell of geometric nonlinearity and the human body was assumed to be rigid. The contact between the body and the garment was modeled as a dynamic sliding interface. The predicted pressure was close to the magnitude of experimental measurements, indicating that the model was able to simulate garment pressure during wear with reasonable accuracy. Wong et al.12 simulated clothing pressure distribution in tight-fit sportswear by using a numerical computational method. Three sets of tight-fit sportswear were simulated on the basis of their mechanical properties. In addition, a 3D human body was also simulated in order to investigate its interaction with sportswear in the wearing process. Results showed that pressure increases significantly around the waist girth until it passes through the pelvis during the wearing process. Meanwhile, pressure begins to increase for other tested body locations. Based on a body contour plot, it was found that pressure distribution was not uniformly distributed and the high-pressure zone was concentrated around the waist girth at the end of the wearing process. The simulated pressure has no significant difference (p > 0.05) with the experimental pressure measurements. Furthermore, subjective pressure comfort rating was linearly correlated with the simulation, suggesting that the simulation method can provide reliable prediction in terms of pressure comfort. This chapter is based on a study of human psychological perception of comfort in aerobic wear from different aspects: fabric handle, wear trial and preference. Fabric handle covers the perception of cool, soft, smooth, prickly, scratchy, heavy and discomfort. The influence of subjects and aerobic wear was also studied. Personal preference was compared with perception of discomfort. One of the main purposes of aerobic wear is to provide comfort to the wearer during exercise. Therefore, perception of nine individual sensations (breathable, clammy, cool, damp, heavy, prickly, scratchy, sticky and tight) and overall clothing comfort during a 20-minute exercise was described. The influence of subjects, aerobic wear and time on the perception of individual sensations and overall comfort was investigated. The relationship between fabric properties and overall comfort was described using a statistical regression model. The comfort performance of different branded aerobic wear was compared.
22.2.1 Participants Thirty-eight young adults (28 female and ten male) aged between 18 and 35 were selected to participate in a psychological sensory wear trial, which
Clothing biosensory engineering
Table 22.1 Basic description of selected aerobic wears
Average weight (g/m2) Average thickness (mm) Content (%)
C = Cotton, L = Lycra, N = Nylon, P = Polyester and S = Spandex.
was conducted in an environmentally controlled chamber. Each participant had a regular body build, which suits small- or medium-sized clothing.
22.2.2 Aerobic wear Eight types of aerobic wear were selected for the trial. Five of them were sold in the market as sportswear and the remaining three were sponsored by one of the Hong Kong fabric manufacturers. The basic description of the aerobic wear is given in Table 22.1.
22.2.3 Hand preference and wear trial Two out of eight tight-fit items were randomly selected and given to each subject to touch and feel with their hands. Subjects were asked to rate six sensations (cool, soft, smooth, prickly, scratchy, heavy) and overall perception of discomfort (discomfort) after they completed the hand judgement for the first sportswear. The rating scales used for hand evaluation and perception of clammy sensation, as an example, are shown in Figs 22.1 and 22.2, respectively. The subjects were then asked to repeat the same procedures for the second item of sportswear in order to complete a wear trial cycle. Each subject was asked to conduct three wear trials cycle in this study.
22.3.1 Influence of subjects The influence of subject age and gender on perceptions of hand feel was analyzed using multivariate ANOVA. Three age groups were used: (1) 18–21, (2) 22–28 and (3) 29–35. In the selection of subjects a convenient
Sensory comfort of aerobic wear Very Aerobic wear Cool Soft
Very I II
I II Warm Hard
22.1 Rating scale for hand evaluation.
Time (min) 0
Sensation Very Clammy 3
5 10 15 20
22.2 Rating scale for clammy sensation.
sampling method was used. The distribution of the three groups was as follows: (1) 18 (47%); (2) 12 (31.6%); (3) 8 (21.1%). There were 28 females and ten males included. The reason for this is that the wear trial consisted of eight garments in total. By using paired comparison, 28 subjects are required. As some of the garments are sold as active tight-fit wear for females only, this reduces the number of available garments for male subjects to five. By using paired comparison, only ten male subjects are required. Therefore, there is a difference in the number of subjects between the two genders. Subject gender had a significant influence (p < 0.05) on the perception of scratchy and prickly, which suggests that these perceptions are different between male and female with average ratings of 44 and 28, respectively. This indicated that males perceived a greater degree of scratchy and prickly sensations than females in this study. Also, the interaction between age group and gender had a significant influence on the perception of cool and soft.
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Table 22.2 Comparison of the mean value of four sensations between eight aerobic wears
Cool Soft Smooth Heavy
56.1 60.6 63.6 46.0
57.6 54.6 52.0 35.4
69.2 65.2 67.7 35.4
54.0 58.7 54.8 58.0
46.0 38.4 33.3 48.0
49.5 60.1 64.7 42.4
73.8 61.9 72.2 57.1
52.4 53.2 46.0 62.0
22.3.2 Influence of aerobic wear N85L15 and P98L2 were rated as the least and the most uncomfortable sportswear, respectively. Subjects found that N85L15 was able to provide the best sensations of cool, soft and smooth amongst the sportswear types. However, R95C gave subjects the least sensations of scratchy and prickly. They also found that N85L15 and N95C were the lightest and heaviest garments, respectively. By comparing the rating of each sensation in terms of sportswear, the result shows that the ratings of cool, soft, smooth and heavy were significantly different amongst the tested sportswear. There was no significant difference among the eight different items of sportswear rating on scratchy, prickly and discomfort sensations. Table 22.2 shows that A92Np and P98L2 had the highest and lowest average scores in relation to the sensations of cool, soft and smooth amongst the eight items of sportswear, respectively. This indicates that subjects are most and least satisfied with the performances of A92Np and P98L2, respectively, in terms of providing the sensations of cool, soft and smooth. Subjects found that C98L2 and N85L15 were the lightest sportswear in the hand evaluation. However, they found N95C was the heaviest garment. The ratings of heaviness of C98L2 and N95C agree with the objective measurement as they are weighted as the lightest and heaviest garments.
22.3.3 Preference of hand evaluation In order to obtain more information relating to subjects’ preferences on sportswear, each subject’s preference score was calculated and used as an indication to describe subject preferences on sportswear. The preference score was calculated on the basis of a count of the number of subject preferences. As mentioned in the previous section, two types of sportswear were given to each subject to evaluate by hand and wear trial. At the end of each evaluation, the subjects were required to select one of the two items of sportswear as their preferred item, which would have a score of 1. The remaining sportswear was given a score of 0. Therefore, the sportswear with
Sensory comfort of aerobic wear
the highest preference score is the most preferred sportswear amongst the subjects. Furthermore, the preference percentage of each sportswear, which is equal to each sportswear preference score divided by the total number of times that it has been tested, was computed. As there were 28 pairs of garments and 38 subjects, in order to ensure that the scoring chances of each possible pair of garments were equal, the preference assessment was assigned to 28 females only. Figure 22.3 illustrates that around 50% of the subjects selected R95C, C98L2 and E95C as their preferred sportswear. However, fewer than 23% of the subjects selected P98L2 and A92Np as their preferred sportswear. This may be explained by the fabric physical property and structure of the sportswear. P98L2 was made of fabrics with rib knitted construction and A92Np was the heaviest garment. However, the above findings do not provide enough information on subject preference in relation to their perceptions. Therefore, the correlation between sensory perceptions and hand evaluation preference score was investigated. Results showed that the sensation soft and smooth have significant correlation with hand 16
Hand evaluation preference score
80 12 70 10
30 4 20 2
Cumulative percentage of preference score (%)
0 R95C C98L2
22.3 Comparison between subjects’ hand evaluation preferences.
Clothing biosensory engineering
evaluation preference, suggesting that the subjects made their preference judgements largely based on the perception of softness and smoothness of sportswear.
Sensory comfort during exercise
22.4.1 Influence of time Figures 22.4a and 22.4b illustrate the behaviour of nine sensory perceptions and overall comfort over time. The subject responses to these sensory perceptions have clear increasing or decreasing trends. Subject perception of breathable, cool and overall comfort decreased considerably. On the other hand, the remaining seven sensations (clammy, sticky, damp, heavy, prickly, scratchy and tight) all have an increasing trend. Also, by comparing the average rating taken from the beginning and at the end of the running trial, clammy, sticky, damp and tight have relatively greater changes in comparison with heavy, prickly and scratchy.
Subjective perception rating
40 Clammy Sticky 30
Breathable Damp Cool
22.4a Subjective rating of thermal moisture-related sensations at different time period.
Sensory comfort of aerobic wear B
Subjetive perception rating
50 Heavy Prickly 40 Scratchy Tight
Overall comfort 20 0
22.4b Subjective rating of other sensations and overall comfort at different time period.
22.4.2 Influence of subject The investigation indicated that subject’s age, gender and the interaction between age and gender have significant influence on the perception of clammy. The average ratings of clamminess of females and males were 24.0 and 31.0, respectively. In terms of age group, the average ratings of age groups 1 and 2 were 28.9 and 22.6, respectively. Furthermore, the average ratings of female and male aged between 22 and 28 were 19.8 and 28.2, respectively. A multivariate ANOVA was carried out to investigate how subject’s age and gender influence other sensory perceptions. The results of the analysis showed that perceptions of clammy, sticky, damp, heavy, prickly, scratchy and overall comfort are significantly different for subjects at different age groups. For instance, the ratings of sticky for the subjects in the 18–21 and 22–28 age groups were 50.0 and 42.6, respectively. This result shows that subjects belonging to the 18–21 age group perceive greater sticky sensation than subjects belonging to the 22–28 age group. Gender has a significant influence on the ratings of all sensory
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perceptions. For instance, the perception ratings of clammy were 45.4 and 55.1 for female and male subjects, respectively. The interaction of age and gender has significant influence on the perceptions of clammy, sticky, damp and heavy, which are moisture related. The average rating of clammy perception by females belonging to the 18–21 age group was 47.0. On the other hand, the average rating of clammy perception by males belonging to the 22–28 age group was 57.2.
Fabric properties and overall comfort performance
In the prediction of clothing comfort using the stepwise regression method, the not so highly related fabric properties were excluded from the model development. Six regression models, each with a different number of fabric properties, were generated. However, only the one with a meaningful model structure and high r2 and adjusted r2 values was selected, as shown in equation (22.1): overall comfort = −6.44 (MIU) + 2.24 (WC) + 2.44 (MWRL) + 1.15 (SMD) + 55.35
where MIU = frictional coefficient, WC = compressional energy, MWRL = maximum wetted radius (lower) and SMD = geometrical roughness. Regression model 22.1 consists of frictional coefficient, compressional energy, maximum wetted radius at the lower fabric surface and geometrical roughness. These physical properties can be represented as the dimensions of moisture, tactile and pressure in relation to clothing comfort, which indicates the major dimensions in the perception of clothing comfort. From previous findings, moisture and thermal sensations can be abstracted into a single sensory factor. Therefore, fabric properties which describe thermal sensation might influence the maximum wetted radius. The limitation of the model is that air permeability, thermal conductivity and thermal insulation were the only three objective measurements related to breathable and thermal sensations. These two types of objective measurements may not be good enough to describe the human perception of thermal comfort. Furthermore, in the investigation of the interrelationship between nine individual sensations, it was found that breathable and cool (thermal), were abstracted into the thermal–wet comfort factor. This suggests that they were correlated. The r2 and adjusted r2 values of regression model 22.1 were 0.974 and 0.940, respectively. Figure 22.5 illustrates that predictions generated from the model involving frictional coefficient, compressional energy, outer maximum wetted radius (lower) and geometrical roughness had the strongest linear
Experimental overall comfort score
65 y = 1.0005x – 0.0346 r = 0.987 60
Predicted overall comfort score
22.5 Fitness of garment overall comfort rating from model 22.1.
relationship with the experimental overall clothing comfort score compared with other models’ predictions. The experimental garment overall comfort rating was highly correlated with the calculated garment overall comfort rating. A good linear relationship was found between the calculated and experimental results, with r ≈ 0.987. Based on the above study, fabric physical properties can be used to predict subjective judgement of hand evaluation, garment pressure comfort, sensory factors and overall clothing comfort by using statistical methods. However, there are some weaknesses in this method. In the development of the regression model, a full set of 33 fabric physical properties’ measurements cannot be used, as it cannot cope with a large volume of information of subjective judgements on the same piece of fabric. Therefore, the fabric physical properties (independent variables) are selected subjectively in order to reduce the number of independent variables. Furthermore, the mean values of fabric physical properties’ measurements and subjects’ ratings have to be used to match the two data sets in the model develop-
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ment process. The consequence of this is that a large volume of information from the subjective evaluation of individual subjects has been lost. The size of the output of the data is also trimmed down from 168 to 8, as there are only eight garments in the trial, which limits the reliability of the models.
Comfort performance of different brands
The perception ratings are significantly different (p < 0.05) among the different garments in this study. For example, the ratings of clammy perception are 54.1, 41.8 and 47.4 for garments N88P, C98L2 and N85L15. This indicates that subjects perceive greater sensation of clamminess with N88P than C98L2 and N85L15. Subjects perceive most and least prickle sensation with P98L2 (49.3) and N95C (27.4), respectively. R95C (69.0) and N95C (50.7) are rated as the loosest and tightest garments, respectively.
This chapter illustrates human perception of individual sensations and overall comfort in aerobic wear through a series of fabric handle and wear trial processes. Based on this study, the following findings are obtained. 1. Fabric handling: • no significant difference between the selected aerobic wear rating on scratchy, prickly and overall discomfort sensations; • males perceived significantly greater degree of scratchy and prickly sensations than females; • subjects made their preference judgements largely based on the perception of the softness and smoothness of the aerobic wear. 2. Wear trial: • time clearly has significant influence on the perception of selected sensations and overall comfort; • the perception of overall comfort is linearly related to four fabric physical properties (1) frictional coefficient; (2) compressional energy; (3) maximum wetted radius (lower) and (4) geometrical roughness; • fabric physical properties can be used to predict subjective judgement of hand evaluation, garment pressure comfort, sensory factors and overall comfort.
The authors would like to thank the Hong Kong Polytechnic University for funding this research through project A174.
Sensory comfort of aerobic wear
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