Effects Of Dynamic Ambient Temperature On Sleep Quality And Thermophysiological Characteristics In Summer

One third of people’s life is spent in sleep.A good sleep is beneficial to both physical and mental health,which is inseparable from the creation of a suitable sleep thermal environment.Comfortable bedroom temperature is conducive to sleep maintenance and development.But a long-term stable thermal environment may also cause health problems.Sleep quality is closely related to environmental changes and human physiological changes.However,temperature designs in existing studies rarely involve physiological changes in the human body.In addition,crossover studies on sleep quality and human physiological parameters are still lacking.It will be a new idea to explore the changes of sleep quality and human physiological characteristics under dynamic environment temperature by combining medical and industrial methods.To explore reasonable temperature during sleep in summer,questionnaires and laboratory experiments methods are used.The influences of constant temperature and humidity environment on human sleep quality and body condition are clarified.In addition,the sleep quality under dynamic temperature are investigated.Besides,the thermal physiological characteristics of human body under different temperature conditions are analyzed.The main works are as follows:First,a questionnaire survey is conducted on the sleep quality and health levels of people in constant temperature and humidity residential environments.Results show that higher sleep quality is reported of the people from constant temperature and humidity residential environments.Meanwhile,these people also exhibited poorer health levels,which is manifested as more illness,longer recovery time after illness,and more likely to catch cold during cold snaps.Second,dynamic temperature conditions of summer sleep are designed based on the physiological changes of human body during sleep.Laboratory experiments are carried out to explore the changes of sleep quality under different temperature conditions.Compared with the thermoneutral constant temperature condition,dynamic temperature conditions can significantly increase the deep sleep duration.Both in the first and second half of sleep,the proportions of deep sleep are higher in dynamic temperature conditions than that in constant temperature condition.Besides,different temperature conditions have no significant effect on self-reported sleep qualityThird,thermophysiological parameters of human body are monitored under different experimental conditions.During the experiment,the skin temperature is affected by the ambient temperature and bedding coverage.Meanwhile,changes in skin and core temperature affect sleep processes.The dynamic temperature during sleep raises Immunoglobulin E(IgE)concentrations,which act as a biomarker of respiratory immunity.The changes of dopamine(DA)concentrations and IgE concentrations before and after sleep are significantly correlated with skin temperature and sleep process.Finally,the subjects’ thermal sensation and thermal comfort votes are collected in different experimental conditions.Compared with constant temperature condition,dynamic temperature conditions improve the thermal sensation and thermal comfort levels after waking up.In addition,how men and women perceive the same ambient temperature significantly affects how long it takes to enter deep sleep.Significant correlations are found between the results of different subjective questionnaires,which reveale the inaccuracy of sleep questionnaires and thermal questionnaires.In summary,two summer sleep dynamic temperature conditions are proposed.Through experiments,dynamic temperature has positive effects on improving sleep quality,thermal comfort levels and IgE concentrations.Skin temperature and core temperature,as intermediate variables of ambient temperature affecting sleep quality,are of great significance in the research.The integrated study of sleep quality and thermophysiological parameters provides basis for dynamic temperature design during sleep.