Study on subjective sensation and physiological reaction with high physical activity influenced by air temperature of stadium

As the main venue for sports training and competition, the thermal environment of a stadium directly could affect the comfort and health of a moving body and sports performance. In this study, the quantitative relationship between ambient temperature and subjective sensation evaluation was established by monitoring the actual thermal sensation evaluation, fatigue sensation cognition and physiological response with high physical activity, under different conditions of ambient temperature. The results show that 90% of subjects can actually accept an ambient temperature range of 18.6°C–26°C. This is 2°C higher than the maximum recommended range in the ISO 7730:2005 thermal comfort standard, reflecting a strong tolerance of the moving human body to low or high temperature environments. A high temperature environment could cause exercise fatigue to occur prematurely. Moreover, the study suggests that the critical point for early occurrence of fatigue sensation in a moving human body is 28°C. The relationship between the environmental temperature and the physiological response was evaluated by mean skin temperature, blood pressure and heart rate of the human body. These are used as evaluation indexes of physiological parameters. Ambient temperature has a significant effect on the objective physiological response of the moving human body, which coincides with the subject’s definition of subjective sensory evaluation to the ambient temperature.

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Required temperature distribution based on clothing insulation and metabolic rate survey in Japan

Indoor and Built Environment ◽

10.1177/1420326x19870232 ◽

2019 ◽

Vol 29 (6) ◽

pp. 775-782

Author(s):

Masanari Ukai ◽

Tatsuo Nobe

Keyword(s):

Physical Activity ◽

Temperature Distribution ◽

Metabolic Rate ◽

Thermal Environment ◽

Thermal Sensation ◽

Metabolic Rates ◽

Clothing Insulation ◽

Office Environment ◽

Temporal And Spatial ◽

Temperature Side

In this study, the authors evaluated clothing insulation and changes in the metabolic rate of individuals in an office environment to determine thermal comfort. Clothing was evaluated using a questionnaire completed by 1306 workers in nine offices. The metabolic rates of 86 workers in three offices were measured using a physical activity meter. The distribution of the temperature at which a person in the room perceived a neutral thermal sensation was then calculated from the determined metabolic rates and clothing insulation values. The results demonstrate a noticeable difference between the average and most frequent values during the summer. Moreover, the required temperature distribution is not normal; rather, it is broad and skewed to the low-temperature side. Therefore, even if a thermally uniform environment is provided at the average required temperature by preventing temporal and spatial variations in the thermal environment, complaints of an unacceptably hot thermal environment are more likely to occur than complaints of an excessively cold thermal environment.

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Effects of solar radiation on thermal sensation and physical fatigue of the human body under heavy-load exercise

Indoor and Built Environment ◽

10.1177/1420326x20974736 ◽

2020 ◽

pp. 1420326X2097473

Author(s):

Yongqiang Xiao ◽

Yaping Gao ◽

Yi Wang ◽

Xiaojing Meng

Keyword(s):

Blood Pressure ◽

Solar Radiation ◽

Ambient Temperature ◽

Human Body ◽

Field Experiments ◽

Physiological Stress ◽

Thermal Sensation ◽

Heavy Load ◽

Solar Radiation Intensity ◽

Significant Difference

Solar radiation intensity affects both subjective reactions and physiological functions, especially for people who exercise heavily. Field experiments including a questionnaire survey at various ambient temperatures were performed; outdoor activities under shading (irradiance I = 50 ± 20 W/m2) and non-shading ( I = 700 ± 50 W/m2) conditions during summer in Xi'an were recorded. The results of questionnaires indicated that when the human body reached an extremely hot state, the corresponding environmental temperature was 3.7 °C lower under the non-shading condition, and the range of actual acceptable temperatures was narrower. In terms of thermal sensation, there was a significant difference for people who exercise heavily and those who do not. The results also showed that the curve of fatigue sensation exhibited an inverse Gaussian distribution. Namely, fatigue was promoted under both colder and hotter conditions. Moreover, under non-shading condition, the lowest fatigue incidence was higher, and the corresponding ambient temperature was lower. Changes in objective physiological responses indicated that the solar radiation might cause heat stress. Therefore, when the ambient temperature was higher than 32 °C, physiological stress was higher. Under the same exercise load, the blood pressure was higher under the non-shading condition and systolic blood pressure increased with ambient temperature.

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A revised method to predict skin’s thermal resistance

Thermal Science ◽

10.2298/tsci1804795w ◽

2018 ◽

Vol 22 (4) ◽

pp. 1795-1802

Author(s):

Lijuan Wang ◽

Ding Chong ◽

Yuhui Di ◽

Hui Yi

Keyword(s):

Heat Flux ◽

High Temperature ◽

Low Temperature ◽

Thermal Resistance ◽

Ambient Temperature ◽

Skin Temperature ◽

Heat Loss ◽

Human Body ◽

New Formula ◽

Sweat Evaporation

Human body can adjust heat loss by vasoconstriction, vasodilatation, and other methods. The purpose of this research is to investigate whether the thermal resistance of skin reflects vasoconstriction and vasodilatation. For this aim, the ambient temperature was controlled as 18.1, 21.6, 24.9, 27, and 30.5?C, respectively. In each temperature, the skin temperature and heat flux in the forearm were recorded. Based on tested data, the thermal resistance was calculated by a common method. The results showed that the thermal resistance at low temperature was less than that at high temperature, which was contrary to the rule of vasoconstriction and vasodilatation. So a new formula for thermal resistance was presented based on skin diffusion, sweat evaporation, and mass transformation. The results showed that the new method could predict vasoconstriction and vasodilatation. The revised equation is a useful index for physiological thermoregulation.

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TRPA1 tunes mosquito thermotaxis to host temperatures

10.1101/027896 ◽

2015 ◽

Author(s):

Roman A Corfas ◽

Leslie B Vosshall

Keyword(s):

High Temperature ◽

Body Temperature ◽

Human Body ◽

Thermal Environment ◽

Ambient Air ◽

Body Temperatures ◽

Host Body ◽

Host Seeking ◽

Thermal Stimuli ◽

Body Heat

While most ectotherms thermotax only to regulate their temperature, female mosquitoes are attracted to human body heat during pursuit of a blood meal. Here we elucidate the basic rules of Aedes aegypti thermotaxis and test the function of candidate thermoreceptors in this important behavior. We show that host-seeking mosquitoes are maximally attracted to thermal stimuli approximating host body temperatures, seeking relative warmth while avoiding both relative cooling and stimuli exceeding host body temperature. We found that the cation channel TRPA1, in addition to playing a conserved role in thermoregulation and chemosensation, is required for this specialized host-selective thermotaxis in mosquitoes. During host-seeking, AaegTRPA1-/- mutants failed to avoid stimuli exceeding host temperature, and were unable to discriminate between host-temperature and high-temperature stimuli. TRPA1-dependent tuning of thermotaxis is likely critical for mosquitoes host-seeking in a complex thermal environment in which humans are warmer than ambient air, but cooler than surrounding sun-warmed surfaces.

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Human transient response under local thermal stimulation

Thermal Science ◽

10.2298/tsci17s1019w ◽

2017 ◽

Vol 21 (suppl. 1) ◽

pp. 19-24

Author(s):

Lijuan Wang ◽

Yudong Wang ◽

Guohua Tian ◽

Yuhui Di

Keyword(s):

Heart Rate ◽

Heat Flux ◽

High Temperature ◽

Transient Response ◽

Human Body ◽

Thermal Sensation ◽

Whole Body ◽

Local Part ◽

Hot Environment ◽

Different Temperatures

Human body can operate physiological thermoregulation system when it is exposed to cold or hot environment. Whether it can do the same work when a local part of body is stimulated by different temperatures? The objective of this paper is to prove it. Twelve subjects are recruited to participate in this experiment. After stabilizing in a comfort environment, their palms are stimulated by a pouch of 39, 36, 33, 30, and 27?C. Subject?s skin temperature, heart rate, heat flux of skin, and thermal sensation are recorded. The results indicate that when local part is suffering from harsh temperature, the whole body is doing physiological thermoregulation. Besides, when the local part is stimulated by high temperature and its thermal sensation is warm, the thermal sensation of whole body can be neutral. What is more, human body is more sensitive to cool stimulation than to warm one. The conclusions are significant to reveal and make full use of physiological thermoregulation.

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Morphological and Functional Effects of the Resistance Training and High Physical Activity of Recreational Type in Young Men

Medical and Biological Sciences ◽

10.2478/mbs-2013-0034 ◽

2013 ◽

Vol 27 (4) ◽

Author(s):

Jadwiga Pietraszewska ◽

Anna Burdukiewicz ◽

Aleksandra Stachoń ◽

Justyna Andrzejewska

Keyword(s):

Physical Activity ◽

Resistance Training ◽

Young Men ◽

High Physical Activity

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INFLUENCE OF AMBIENT TEMPERATURE ON CENTRAL AND PERIPHERAL IMPEDANCE MEASUREMENTS OF THE HUMAN BODY

Environmental Engineering and Management Journal ◽

10.30638/eemj.2011.072 ◽

2011 ◽

Vol 10 (4) ◽

pp. 511-517 ◽

Cited By ~ 2

Author(s):

Calin Corciova ◽

Radu Ciorap ◽

Dan Zaharia ◽

Alexandru Salceanu

Keyword(s):

Ambient Temperature ◽

Human Body ◽

Impedance Measurements

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The subjective sensation induced by various thermal pulse stimulation in healthy volunteers

Scandinavian Journal of Pain ◽

10.1016/j.sjpain.2017.04.039 ◽

2017 ◽

Vol 16 (1) ◽

pp. 177-178

Author(s):

Y. Oono ◽

H. Kubo ◽

T. Imamura ◽

K. Matsumoto ◽

S. Uchida ◽

...

Keyword(s):

Healthy Volunteers ◽

Thermal Sensation ◽

Heat Pulse ◽

Peltier Element ◽

Cold Pain ◽

Thermal Pulse ◽

Heat Sensation ◽

Thermal Stimulator ◽

Subjective Sensation ◽

Pulse Stimulation

AbstractAimsNovel quantitative thermal stimulator devices (QTSDs) have been developed to deliver thermal pulse stimulation with regulated constant temperatures (0–45°C) with a Peltier element probe (16 cm2). The aim of this study was to investigate subjective sensation induced by the interaction between simultaneously applied painful cold and heat stimuli in various sites.MethodsTwenty healthy subjects (12 men and 8 women, age range: 25–45 years) participated. The intensity of cold pain (CP) and heat pain (HP) stimuli were assessed by visual analogue scale (VAS) and adjusted to elicit approximately 70/100 mm. Alternately pulse stimulations (pulse duration of 40 s; 0.025 Hz) which consisted of CP, HP, or neutral temperature (32°C) were applied. Four conditions were tested and subjective sensations were assessed: (1) one QTSD was applied to non-dominant forearm and cold-heat pulse stimulation was applied.Two QTSDs were applied to (2) non-dominant ipsilateral forearm with 5 cm apart, (3) non-dominant and contralateral forearms, (4) non-dominant forearm and ipsilateral thigh, respectively. In conditions of (2)–(4), CP-neutral pulse stimulation (C-Neutral) and neutral-HP pulse stimulation (Neutral-H) were applied simultaneously with opposite phase, respectively.ResultsCP and HP were 3.9±1.0°C (mean±SD) and 43.6±0.9°C (mean±SD), respectively. The VAS values for CP and HP were 73.4±2.0 mm (mean±SD) and 76.4 ±4.8 mm (mean±SD), respectively. Some subjects could not discriminate cold or heat sensation and some felt cold as heat (paradoxical sensation). The number of subjects with such paradoxical sensation in (1), (2), (3), (4) were 9 (45%), 2 (10%), 0 (0%) and 3 (15%), respectively.ConclusionsIn healthy volunteers, simultaneous alternately cold-heat pulse stimulation on one site triggered paradoxical thermal sensation, which to a much less degree is triggered when C-Neutral and Neutral-H were applied to different dermatomes. This suggests that the mechanism is primarily triggered peripherally.

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