Many Japanese women have trouble with cold hands and feet. We examined how the skin temperature of the hands and feet are related to the environmental temperature. The subjects were eight otherwise healthy women aged 20-22 years, who complained of cold hands and feet. The dorsal and ventral skin temperatures of the hands and feet of a subject were measured using a thermotracer over two menstrual cycles. As the outside temperature and temperature in the bedroom increased from spring to summer, both the basal body and skin temperature of the hands and feet increased. However, the skin temperature of the hands and feet did not change with the basal body temperature, but were influenced more by the increase in bedroom temperature. Therefore, we compared subjects who woke up in a bedroom warmed to about 22℃ with those who woke in a bedroom at a normal winter temperature of about 9.6℃. During the low phase of body temperate, the basal body temperature and skin temperature of the hands of the subjects were significantly higher in the warmed bedroom. In other words, on warming the bedroom temperature in winter, the thermoregulatory center was under the illusion that it was spring or early summer, which played a dominant role in altering the circulation to the hands and feet.

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We have focused the spontaneous rhythmic skin blood flow fluctuation (the vasomotion or the basic wave, main frequency around 0.1Hz) measured with the laser Doppler flowmetry as an index of autonomic nervous activity. The purposes of this basic study were to find suitable measuring points of the skin blood flow and to find the evaluation method of vasomotion by comparing the HRV parameters. We measured the skin blood flow on 3 points (forehead, left earlobe and nose point) and ECG simultaneously. As the experimental tasks, the posture differences (supine, sitting and standing) and mental task (1 digit adding task)) were used. 11 male subjects and 11 female subjects were participated to this experiment. From the results, 1) the suitable measuring points of the vasomotion are earlobe and forehead. 2) LF/HF ratio and HF of HRV showed significant change among posture difference, but the vasomotion parameter did not show the significant change. This result suggests that the experimental task influenced mainly the cardio vascular indices, and the vasomotion parameter in this experiment might not be suitable to evaluate these dynamic changes.

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L-theanine is one of the major amino acids, predominantly found in green tea leaves. Historically, this amino acid has been known as a relaxing agent. The current study examined the effects of L-theanine and a placebo on the automatic nervous system during sleep, using the pulse frequency demolition method. For this purpose, a cross over double blind study was performed on 20 females who were in their postmenopausal period and of 57.3±3.9 years old. During the study, each participant ingested 200mg of L-theanine or placebo before sleeping, for six consecutive days. The results showed that L-theanine significantly inhibited the excitement of the sympathetic nervous system and tended to noticeable enhance the activity of the parasympathetic nervous system, during sleep. Thus, the physiological effect of L-theanine on the automatic nervous system as estimated, was found to play a role in improving the quality of sleep. This study suggested that L-theanine was useful for promoting comfortable living states.

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Characteristic motions during putting on and taking off underwear and pants-type diapers were clarified by a comparison between young and elderly persons. We performed subjective evaluation, motion analysis, electromyography and stabiliometry during the activity of putting on and taking off underwear and pants-type diapers. As a result of this study it was predicted that lowering the head and wrist positions places a heavy burden on elderly persons because their body flexibility, muscle strength, and balance are reduced. It is important to design pants-type diapers that reduce senile body-specific burden.

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The purpose of this research is to examine the effects of product usability on psychological and physiological indices of users, and to propose an effective evaluation method for measuring users' emotion while interacting with a product. Frequency-rhythm of brain waves of product users were measured as a physiological index by using the HSK central rhythm monitoring system (provided by HUMAN SENSING Co., Ltd.). In study 1, we proved that the degree of comfort in the use of a good usability product is higher than a bad usability product, by measuring users' brain waves. In study 2, the result of measuring brain waves with 4 products showed that the degree of comfort measured with brain waves has linear relations with the existing indices "the degree of achievement" and "subjective evaluation of mood". By this method we could evaluate the delicate shades of users' mood quantitatively, that we couldn't confirm by existing indices ("degree of achievement" and "subjective evaluation and others"). In the next phase, we'll accumulate case studies and try to measure users' emotion (KANSEI), for example, pleasantness, satisfaction, comfort and so on, while interacting with a product.

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The purpose of this study is to present the results from the survey of physiological and psychological reactions to health care on high altitude trekking. Subjects were eleven middle-aged female mountain trekkers of a mountaineering club. They were classified into two groups; one is seven subjects who performed all the trips (the completed group, group C) and the other is four subjects who descended a mountain because of their poor physical conditions (the descended group, group D). And then about these two groups physiological and psychological reactions in the high altitude trekking were discussed. As a result, it was shown that the measurements of pulse rate and SpO2 as the physiological index were effective in evaluating physical conditions when trekking. In addition, although RPC (Rating of Physical Condition) designed for making a psychological index is a simple and easy method, it was found to be an effective way to predict the extent of their mental fatigue. It is suggested from these results that the observation of physiological and psychological reactions is effective for health care on high altitude trekking and for prevention against sickness including AMS (acute mountain sickness).

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Many Japanese women have trouble with cold hands and feet. We reported how the skin temperature of the hands and feet are related to the environmental temperature in previous paper. As the outside temperature and the temperature in the bedroom increased from spring to summer, both the basal body and skin temperature of the hands and feet increased. However, the skin temperature of the hands and feet did not change with the basal body temperature, but were influenced more by the increase in bedroom temperature. The subjects were two otherwise healthy women aged 21 years, who complained of cold hands and feet. The dorsal and ventral skin temperatures of the hands and feet of a subject were measured using a thermotracer. Therefore, we compared subjects who woke up in a bedroom warmed to about 22-24℃ with those who woke in a bedroom at a normal winter temperature of about 9-17℃. During the low phase of body temperature, the basal body temperature and skin temperature of the hands of the subjects were significantly higher in the warmed bedroom. By contrast, during the high phase of body temperature, the skin temperature was relatively low, although the basal body temperature rose when we warmed the bedroom temperature. It was suggested that on warming the bedroom temperature of about 22℃ during high phase of body temperature in winter, skin temperature decreased because the basal body temperature was too high and her palm were sweating.

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