Thermo-Physiological Comfort Properties of Sportswear with Different Combination of Inner and Outer Layers

Consumers expect high-performance functionality from sportswear. To meet athletic and leisure-time activity requirements, further research needs to be carried out. Sportswear layers and their specific thermal qualities, as well as the set and air layer between materials, are all important factors in sports clothing. This research aims to examine the thermal properties of sports fabrics, and how they are affected by structure parameters and maintained with different layers. Three inner and four outer layers of fabric were used to make 12 sets of sportswear in this study. Before the combination of outer and inner layers, thermal properties were measured for each individual layer. Finally, the thermal resistance, thermal conductivity, thermal absorptivity, peak heat flow density ratio, stationary heat flow density, and water vapor permeability of bi-layered sportswear were evaluated and analyzed. The findings show that sportswear made from a 60% cotton/30% polyester/10% elastane inner layer and a 100% polyester outer layer had the maximum thermal resistance of 61.16 (×10³ K·m² W⁻¹). This performance was followed by the sample made from a 90% polyester/10% elastane inner layer and a 100% polyester outer layer, and the sample composed of a 100% elastane inner layer and a 100% polyester outer layer, which achieved a thermal resistance value of 60.41 and 59.41 (×10³ K·m² W⁻¹), respectively. These results can be explained by the fact that thicker textiles have a higher thermal resistance. This high-thermal-resistance sportswear fabric is appropriate for the winter season. Sportswear with a 90% polyester/10% elastane inner layer had worse water vapor resistance than sportswear with a 60% cotton/30% polyester/10% elastane and a 100% elastane layer. Therefore, these sports clothes have a higher breathability and can provide the wearers with very good comfort. According to the findings, water vapor permeability of bi-layered sportswear is influenced by geometric characteristics and material properties.     

Comfort Evaluation of Wearable Functional Textiles

Wearable E-textile systems should be comfortable so that highest efficiency of their functionality can be achieved. The development of electronic textiles (functional textiles) as a wearable technology for various applications has intensified the use of flexible wearable functional textiles instead of wearable electronics. However, the wearable functional textiles still bring comfort complications during wear. The purpose of this review paper is to sightsee and recap recent developments in the field of functional textile comfort evaluation systems. For textile-based materials which have close contact to the skin, clothing comfort is a fundamental necessity. In this paper, the effects of functional finishing on the comfort of the textile material were reviewed. A brief review of clothing comfort evaluations for textile fabrics based on subjective and objective techniques was conducted. The reasons behind the necessity for sensory evaluation for smart and functional clothing have been presented. The existing works of literature on comfort evaluation techniques applied to functional fabrics have been reviewed. Statistical and soft computing/artificial intelligence presentations from selected fabric comfort studies were also reviewed. Challenges of smart textiles and its future highlighted. Some experimental results were presented to support the review. From the aforementioned reviews, it is noted that the electronics clothing comfort evaluation of smart/functional fabrics needs more focus.     

Modeling and Simulation of Human Body Heat Transfer System Based on Air Space Values in 3D Clothing Model

Comfort can be considered as subjective feeling, which could be affected by the external ambient, by the physical activity, and by clothing. Considering the human body heat transfer system, it mainly depends on various parameters including clothing materials, external and internal environment, etc. The purpose of the current paper is to study and establish a quantitative relationship between one of the clothing parameters, ease allowance (air gap values) and the heat transfer through the human body to clothing materials and then to the environment. The study considered clothing which is integrated with the 3D ease allowance from the anthropometric and morphological data. Such incorporating of the clothing’s 3D ease control was essential to properly manage the air space between the body and the proposed clothing thermal regulation model. In the context of thermal comfort, a clothing system consisting of the human body, an ease allowance under clothing, a layer of textile materials, and a peripheral layer adjacent to the textile material was used. For the complete system, the heat transfer from the skin to the environment, which is influenced by thermoregulation of the human body, air gap, tissue, and environmental conditions were also considered. To model and predict the heat transfer between the human body and the temperature of skin and clothes, a 3D adaptive garment which could be adjusted with ease allowance was used. In the paper, a thermoregulatory model was developed and proposed to predict the temperature and heat within clothing material, skin, and air space. Based on the result, in general the main difference in the temperature of clothing and skin from segment to segment is due to the uneven distribution of air layers under the clothing.     

Material and Structural Functionalization of Knitted Fabrics for Sportswear

Comfort is an important quality criterion, especially for sportswear. It influences well-being, performance and efficiency. The necessary dissipation of heat and air flow, at high metabolic rates, must be designed and planned in advance. The influence of structure, density, mass and thickness of fabric were considered as well as yarn material composition, yarn linear density, yarn evenness and yarn hairiness. The influence of the mentioned parameters on thermal properties and air permeability was calculated. From the correlation analysis, it can be concluded that yarn’s linear density, yarn short fibers hairiness, and mass per unit area of knitted fabric has the greatest impact on heat resistance. The yarn linear density, the yarn hairiness of the longer protruding fibers, and the thickness of the knitted fabric have the greatest impact on air permeability. A statistically significant model of multiple linear regression equations was offered to predict the thermal comfort of knitted fabric.     

心导管术后人工压迫止血无包扎对患者舒适度的影响

目的评价经皮股动脉冠状动脉介入诊疗术、人工压迫止血后无包扎对患者舒适度的影响。方法204例经皮股动脉冠状动脉造影或介入治疗的患者,按止血方法分为无包扎组即观察组123例（造影94例,介入治疗29例）和传统压迫组即对照组81例（造影38例,介入治疗43例）。观察组止血后4h床上活动,6h下地。对照组止血后12h下地活动。对比两组患者的舒适度。结果观察组患者舒适度明显优于对照组（P〈0．001）。结论心导管术后人工压迫止血无包扎4h床上活动,6h下地能提高患者舒适度,减轻腰背酸痛、排尿困难等不适,减少患者卧床痛苦。     

Effect of moderate and high intensity chronic exercise on the pancreatic islet morphometry in healthy rats: BDNF receptor participation

The function and morphology of β-cells is largely dependent on insulin demand. As β-cells cover a bigger cell proportion in pancreas islets, changes of insulin producer cells affect the whole pancreatic islet morphology. Growth factors as the neurotrophins regulate the pancreas physiology, besides; physical exercise increases insulin sensitivity, and further modifies brain derived neurotrophic factor (BDNF) concentration in plasma. The aim of this study was to investigate the effects of chronic exercise (running in a treadmill for 8 weeks) intensity on pancreatic islet morphometry in healthy state. The BDNF receptor effect on the pancreatic islet morphometry was also evaluated. Adult male Wistar rats were divided in 6 groups: Control (C); moderate intensity training (MIT); high intensity training (HIT) did not treat with BDNF receptor inhibitor (K252a), and C, MIT and HIT treated with K252a. The results shown that chronic exercise induces β-cells hypertrophy without BDNF receptor participation. On the other hand, the moderate exercise increases the number of β cells per islet; the last effect does not require TrkB participation. In sedentary conditions, the K252a treatment reduced the β-cell density. Exercise intensity has differential effects on pancreas islet morphometry in healthy model; furthermore, BDNF receptor plays a role to maintain the amount of β-cells in sedentary state.     

The effectiveness of permethrin and deet, alone or in combination, for protection against Aedes taeniorhynchus

Field tests were conducted to compare the degree of protection from bites by the mosquito Aedes taeniorhynchus (Wiedemann) provided by wearing clothing treated with permethrin [(3-phenoxyphenyl)methyl (+/-) cis/trans 3-(2-dichloroethenyl)2, 2-dimethylcyclopropanecarboxylate] with that provided by applying deet (N,N-diethyl-m-toluamide) to exposed skin or by applying deet and wearing the treated clothing. Human test subjects were exposed to natural populations of mosquitoes for a 9-hour daytime period (total of 8 days/treatment) while using one or both protection methods. Unprotected test subjects were also exposed for short periods each day as a check to determine the overall biting rate of mosquitoes. The combined use of both protection methods was the most effective treatment in preventing bites, resulting in an average of 1.5 bites/9-hour day, compared with 53.5 and 98.5 bites on subjects protected only with treated clothing or deet, respectively, and 2,287 bites (extrapolated) on subjects who wore untreated clothing during the same time period. Measurements also indicated that the toxic effect of permethrin reduced biting rates by greater than 90% within the immediate area where subjects wore permethrin-treated uniforms for 9 hours.     

Assessment of the Impact of Clothing Structures for Premature Babies on Biophysical Properties

This article presents research on ergonomics and physiological comfort of protective clothing. Biophysical properties of selected three-layer textile assemblies that differ in geometry and raw material composition for the production of types of mummy sleeping bags for premature babies were investigated. The tests included measurements of air permeability, thermal resistance and water vapor resistance (both by means of human skin model), thermal insulation, and water vapor resistance (both using newborn manikin). Experimental research was supplemented by modeling the thermal insulation of the assemblies by designing their 3D models using selected CAD software and applying the finite volume method. The obtained results allowed the evaluation of the influence of different geometry and the raw material composition of the proposed assemblies on the performance parameters of protective clothing.     

Seasonal difference in the occurrence of exercise-induced bronchospasm in asthmatics: dependence on humidity

BACKGROUND: Most studies on the effects of temperature and humidity on exercise-induced bronchospasm (EIB) in asthmatics have been carried out under indoor conditions. However, any asthmatic patient is exposed to varying climatic conditions. OBJECTIVE: To investigate whether temperature or relative humidity plays a more important role in determining the degree of EIB in asthmatics under naturally exposed climate conditions. METHODS: To exclude the effects of pollen on EIB, we enrolled 69 subjects with perennial asthma (mean +/- SD: 20.1 +/- 1.5 years). The subjects performed outdoor free running tests. They were divided into winter (n = 25), spring/autumn (n = 22), and summer (n = 22) groups according to the season when they performed the tests. Initial spirometry and skin prick tests were performed. Methacholine bronchial challenge testing and, one day later, the free running tests were done. RESULTS: There were significant differences in temperature and relative humidity among the three groups: However, the relative humidity in winter did not differ from that in spring/autumn. There were no differences in pulmonary functions, airway responsiveness, and atopy score among the three groups. The percentage of cases of positive EIB --fall in forced expiratory volume in 1s FEV(1) of >15% from baseline --in winter (84%, p < 0.05) or spring/autumn (86.4%, p < 0.05) was higher than that in summer (50%). However, the percentage of subjects with a positive EIB in winter did not differ from that in spring/autumn. The maximal percent fall in FEV(1) after exercise in winter did not differ from that in spring/autumn. CONCLUSIONS: The occurrence of EIB is associated with environmental temperature and humidity. Under such climatic conditions as in Korea, relative humidity may be a more important factor than temperature in contributing to EIB in patients with perennial asthma.     

The Influence of Electro-Conductive Compression Knits Wearing Conditions on Heating Characteristics

Textile-based heaters have opened new opportunities for next-generation smart heating devices. This experiment presents electrically conductive textiles for heat generation in orthopaedic compression supports. The main goal was to investigate the influence of frequent washing and stretching on heat generation durability of constructed compression knitted structures. The silver coated polyamide yarns were used to knit a half-Milano rib structure containing elastomeric inlay-yarn. Dimensional stability of the knitted fabric and morphological changes of the silver coated electro-conductive yarns were investigated during every wash cycle. The results revealed that temperature becomes stable within two minutes for all investigated fabrics. The heat generation was found to be dependent on the stretching, mostly due to the changing surface area; and it should be considered during the development of heated compression knits. Washing negatively influences the heat-generating capacity on the fabric due to the surface damage caused by the mechanical and chemical interaction during washing. The higher number of silver-coated filaments in the electro-conductive yarn and the knitted structure, protecting the electro-conductive yarn from mechanical abrasion, may ensure higher durability of heating characteristics.     

Hyperventilation syndrome and the assessment of treatment for functional cardiac symptoms.

Three methods of breathing retraining (guided breathing retraining, guided breathing retraining with physiologic monitoring of thoracic and abdominal movement plus peripheral temperature, and guided breathing retraining with physiologic monitoring of thoracic and abdominal movement, peripheral temperature and end-tidal carbon dioxide) were compared with a no-treatment control group to determine the effectiveness of breathing retraining on modifying respiratory physiology and reducing functional cardiac symptoms in subjects with signs associated with hyperventilation syndrome. Of 41 subjects studied, 16 were diagnosed with mitral valve prolapse. Results demonstrated that all 3 methods of breathing retraining were equally effective in modifying respiratory physiology and reducing the frequency of functional cardiac symptoms. Results determined that respiratory rate and subject's perception that training had generalized were the best predictors of treatment success. Furthermore, it was found that subjects with mitral valve prolapse responded as well to treatment as did those without prolapse.     

Echocardiographic parameters in athlete and nonathlete offspring of hypertensive parents

BACKGROUND: According to several reports, some cardiovascular signs of hypertension (left ventricular [LV] hypertrophy, impaired diastolic filling) can be found in the normotensive offspring of hypertensive parents. It is also well known that regular physical exercise decreases the risk of hypertension. AIM: The aim of the present study is to determine whether or not regular physical training influences these early hypertensive traits in the offspring of hypertensive parents. METHODS: Echocardiographic data of 215 (144 males, 71 females) 22- to 35-year-old nonathlete and athlete offspring of hypertensive (positive family history, FH+) and normotensive parents (negative family history, FH-) were compared in a cross-sectional design. RESULTS: In the nonathlete FH+ males and females, LV dimensions were not larger than in the FH- subjects. The E/A quotient was lower in the FH+ subjects in both genders. Absolute and heart rate adjusted isovolumetric relaxation times were slightly longer in the FH+ men than in their FH- peers. No differences were seen between athlete FH- and FH+ subjects. CONCLUSION: Regular physical exercise decreases the incidence of the adverse cardiac signs, which can be associated with hypertension in the normotensive offspring of hypertensive parents.     

Effect of gastric myoelectric activity on carbohydrate absorption of fruit juice in children

Juices have a different rate of gastric emptying than other foods. This may alter the rate of delivery of carbohydrates to the small bowel for absorption. The aim of the study is to demonstrate that faster gastric emptying is associated with greater production of hydrogen through a randomized, crossover study of 39 healthy children. The electrogastrography (indicator of the gastric myoelectric activities) and breath hydrogen tests (indicator of carbohydrate malabsorption) were performed at baseline and after ingestion of 240 to 330 mL of grape or pear juice given in a random order. The cutaneous electrogastrogram was analyzed by running spectral analysis to compute pre- and postprandial period dominant power (PDP) and running spectrum total power (RSTP). Postprandial PDP and RSTP were higher (p < 0.02) in the pear juice group than in the grape juice group, suggesting higher antral myoelectric activities. Twenty three percent of the subjects had significant movement artifacts that suggested discomfort after drinking pear juice compared to 5% after grape juice (p < 0.03). Breath hydrogen test was more frequently positive (increase >20 part per million [ppm] above baseline) after pear juice (52.2%; mean, 36 +/- 33 ppm) than after grape juice (4.3%, 6 +/- 6 ppm). In a multiple regression analysis, the most predictive independent variable of hydrogen concentration was found to be either postprandial PDP (r2 = 0.24; p < 0.002), or RSTP (r2 = 0.37; p < 0.001). Juices affect gastric myoelectric activity. Grape juice induces lower antral myoelectric activities and is better absorbed. The malabsorption of carbohydrates of juices is in part related to their effect on the gastric physiology.     

Shoe sole thickness and hardness influence balance in older men.

OBJECTIVE: To test the hypothesis that shoes with thick, soft midsoles, such as modern running shoes, provide better stability in older individuals than those with thin-hard midsoles. In addition, we examined the relation between footwear comfort and stability and stability when barefoot. DESIGN: Randomized-order, cross-over, controlled comparison. SETTING: Subjects were drawn from an internal medicine practice. PARTICIPANTS: A random sample of 25 healthy men, minimum age 60 years. Additional selection criteria were absence of disabilities influencing ability to walk and lack of history of frequent falls. MEASUREMENTS: Balance failure frequency, which was defined as falls from the beam per 100 meters of beam walking when 10 passes were made down a 9 M long balance beam. Comfort rating was based on an ordinal scale. RESULTS: Contrary to the hypothesis: (1) midsole softness was associated with poor stability (F(2,48) = 17.9, P < 0.0001); (2) thick midsoles also provided poor stability (F(1,24) = 7.36, P < 0.01). When barefoot, subjects showed 19% higher balance failure frequency than with the poorest shoe and 171% greater than the best shoe (t = 5.33, P < 0.0001). Higher comfort was generally found in shoe types associated with higher balance failure frequency. CONCLUSIONS: For optimal stability, shoes with thin, hard soles are preferable for older individuals. Health professionals should exercise caution when recommending shoes with thick, yielding midsoles, such as running shoes, to unstable elderly individuals. Older men and women with a history of falls or who are obviously unstable, should avoid barefoot locomotion.     

The effect of posture and exercise on elastic stocking compression at different sites of the leg.

BACKGROUND: In compression therapy, the importance of the degree of pressure has been emphasized. The aim of this study was to examine the influence of posture and exercise on the compression at different sites of the leg. PATIENTS AND METHODS: In 16 normal volunteers, the pressure was determined simultaneously at 5 sites on the leg during lying, sitting, standing, walking, running, knee-bending exercise and squatting using an air pack type analyzer. Pressure was measured under 3 experimental conditions: with a thigh-length gradient stocking, with foam rubber pads included under the elastic stocking, and after removal of both elastic stocking and compression pads. RESULTS: When the stocking was worn, a pressure gradient was observed in the proximal direction during the sequence from the supine position to running. When the pads were included, the pressure in the supine position was significantly elevated at all sites examined, and the graduated pressure drop was also maintained from supine position to running. However, the pressure at the tibia was significantly higher than that at the gastrocnemius in both supine and sitting positions when the pads were used, while no significant difference was observed between both sites in the standing position. A marked increase in pressure at the ankle, gastrocnemius, and hollow of the knee was observed during squatting when the stocking was worn either with or without pads, while a significant decrease in pressure was observed at the tibia. CONCLUSION: The pressure exerted by elastic stockings varies with the posture and exercise. Furthermore, the changes in pressure vary from site to site.     

Ascending Colon Compression by Psoas Muscle Hypertrophy

Extrinsic compression of the ascending colon was observed on the barium enema of a professional athlete. Ultrasound examination demonstrated psoas muscle enlargement as the cause of this abnormal radiographic finding. The effect of psoas muscle hypertrophy should he considered when extrinsic compression of the colon is observed on the barium enema of muscular individuals. Ultrasound is useful to differentiate anatomic variant from pathological conditions which may deviate the ureters and/or the ascending colon.     

Gastric lesions secondary to long-distance running

Gastrointestinal disorders have been reported during long- distance running. The purpose of this study was to evaluate the effects of prolonged exercise on the upper digestive tract. Seven subjects were submitted to a standard endoscopic examination of the upper digestive tract before and after long- distance running (range 18– 50 km). Mucosal biopsy specimens were taken during all endoscopies. After running, all runners had histologically pathological features in the stomach. Vascular lesions were present in the chorion in six subjects after running, with the intensity of the lesions ranging from congestion to hemorrhage. Postexercise histological examination also showed a decrease in mucosal secretion. These lesions secondary to prolonged exercise indicate the presence of hemodynamic perturbations in the upper digestive tract.     

Arterial compression of the retro-olivary sulcus of the ventrolateral medulla in essential hypertension and diabetes

Pulsatile arterial compression in the retro-olivary sulcus along the surface of the ventrolateral medulla has been postulated as a mechanism in both essential hypertension and diabetes. The objective of this study was to test the independent effect of arterial compression in the retro-olivary sulcus on each of these diseases, using separate logistic regression models to control for other known risk factors. Study design was case-control. The study population consisted of 147 consecutive patients treated for neurological conditions requiring MRI of the posterior cranial fossa. Information on essential hypertension, diabetes, and risk factors for each disease was abstracted from medical records. Presence of arterial compression was determined by blinded review of magnetic resonance images. In the essential hypertension analysis, odds of arterial compression among hypertensive patients were 2.99-times the odds among normotensive subjects (P=0.04), controlling for hypertension risk factors such as age, body mass index, race, diabetes, and family history of hypertension. Of compressed hypertensive subjects, 56% were compressed on the left and 44% were compressed on the right. In the diabetes analysis, odds of arterial compression among diabetic subjects were 1.14-times the odds among nondiabetic subjects (P=0.83). Of compressed diabetic subjects, 60% were compressed on the left, and 40% were compressed on the right. Results suggest that arterial compression of the retro-olivary sulcus may be an independent risk factor for essential hypertension in this population, supporting the postulate for a treatable (with microvascular decompression) neural mechanism for essential hypertension. However, in the diabetic population, the slight increase in the odds of arterial compression was not significant.     

Variations in venous physiology in the healthy subject. Postural and venous occlusion plethysmography studies

The principal characteristic of the venous network is its distensibility, the reason for its role as blood reservoir and cardiovascular adaptation system. This distensibility varies continuously as a function of venous tone, of neurocardiovascular adaptation and of the method used for its determination. The importance of variability of venous physiology was investigated by postural and venous occlusion plethysmography. Two series of tests were performed in 3 healthy volunteers, each being treated over one month: one series involved 19 determinations during May 1985, the other 14 determinations in December 1985. Two plethysmographic methods were employed: conventional venous occlusion plethysmography in decubitus with compression of 50 mm Hg and postural plethysmography with venous occlusion only, using gravity force during variations in position of subjects. Venous filling, a function of venous distensibility, varied between 16.7 and 17.8% during venous occlusion and 23.9 and 31.7% during postural plethysmography. Emptying half-life was from 20.7 to 40.7%. Emptying rate was, by the 6th second, 17.3 to 21.6% for venous occlusion and 27.3 to 32.3% for postural plethysmography. A relation was not found between results for the two methods, suggesting that they explore different phenomena. Variability of venous physiology parameters is marked, modulations being due to general or local factors, the former acting on both legs simultaneously: exterior temperature, neurocardiovascular physiology, digestion, stress, relaxation. Factors can have their effects reduced by differential study of the two limbs.(ABSTRACT TRUNCATED AT 250 WORDS)     

Interrelationships among body composition, blood rheology and exercise performance

It is well known that body composition influences blood rheology (higher blood viscosity and RBC aggregation in obese individuals). On the other hand, blood rheology is related to exercise performance (the fitter the athlete the more fluid the blood). The 'paradox of hematocrit' is that most of the time trained athletes have a lower hematocrit while doping aims at increasing it, a situation which seems to challenge physiology and can be explained by the fact that systemic hematocrit may have poor physiological relevance at the microcirculatory level in exercising muscles. However, recent studies dealing with the marked differences among hemorheologic profiles observed in selected sports lead to the concept that the relationships between hemorheology and performance on one hand and body composition and hemorheology on the other hand are more complex and somewhat different according to the variety of exercise and the physiological and/or pathophysiological background. Increased fat mass, but also fat free mass independently of fat mass, are both correlated to impairments of blood fluidity, consistent with the emerging concept that beside increases in fat mass, increases in fat free mass may also be related to metabolic and circulatory disturbances.