The metabolic and cardiovascular responses of 5 male students, 21-24 years of age, were studied at rest and during submaximal work when they were exposed to ambient temperatures of 6°C and 26°C with relative humidity 50%. On entering the experimental condition, each subject was seated on the bicycle ergometer for 40-41 min rest period, and then performed 8-9 min bout of bicycle ergometer work with pedaling frequency 50 r.p.m., at loads of 300, 600 and 900 kgm/min. Metabolic and cardiovascular parameters were observed during the last 3 -4 min of each rest and work period. In the condition of 6°C, at rest and 300, 600 kgm/min, oxygen uptake, cardiac output and stroke volume increased when compared with the values observed at 26°C. However, at 900 kgml min, no difference was found between 6°C and 26°C. On the other hand, when these cardiovascu-lar parameters were plotted against oxygen uptake, no difference between 6°C and 26°C was found in cardiac output and arterio-venous oxygen difference. However, at the same values of oxygen uptake within the range up to 2.0 l/min, stroke volume at 6°C was 20-30 ml/beat larger and heart rate at 6°C was 15-20 beats/min smaller than the values seen at 26°C.

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Eight healthy male Japanese were exposed to different heat stress, i.e., metabolic heai production during work, high ambient temperature and both of them. After resting on a chair for 30 min. at 28°C with 50% R.H., subjects were examined for 61 min. at following conditions: bicycle ergometer work at 28°C with 50% R.H., rest on a chair at 45°C with 50% R.H. and bicycle ergometer work at 45°C with 50% R.H.. The work load of bicycle ergometer was 450 kgrn/min, and the pedalling frequency was kept at 50 rpm. At the condition of work at 45°C, exposure was stopped due to rise in rectal temperature to 39.0°C, subjective impossibility to continue the work and objective observation. All of the eight subjects could not complete the work for 61 min. at 45°C because of some of the criteria descrived above. The mean value of duration of work at 45°C was 39.4 min.. At the end of the resting period at 28°C, rectal and skin temperature measurements and expired gas collection for 3 min. were made. During exposure period, rectal and skin temperature were measured at every 2 and I min., respectively. Expired gas was collected at 8-11, 28-31 and 58-61 min, during exposure period. The sites of skin temperature measurement were chest. upper arm, thigh and leg. Oxygen uptake was used to calculate the heat production. Body heat content was calculated by rectal temperature and skin temperature, and heat dissipation by heat production and increase in body heat content. During work at 45°C, rectal temperature rised rapidly and there was remarkable heat storage because high ambient temperature disturbed heat dissipation from body to environment. During work at 28°C, there was no significant heat storage though rectal temperature rised. At rest at 45°C, rectal temperature rised due to heat invation from environment to body, and there was significant heat storage.

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Oxygen consumption (VO₂), heart rates (HR), ventilation (VE) blood lactate (LA) and rectal temperature (Tr) were measured at three different water temperatures (18.0, 22.0, and 26.0°C) using under water bicycle ergometer. Subjects consisted three girls and six boys aged 10-12 years. t02 was lineary related to the work loads in 18.0°C than 22.0 and 26.0°C. HR were lower at 18.00C compared to 22.0 and 26.0°C at lower work loads. However there was no significant difference among three different water temperatures. Maximal oxygen uptake (VO₂max) did not differ at any water temperatures. Higher tE at 18.00C than 22.0 and 26.0°C. There was no significant difference between 18.0 and 22.00C. Blood lactate concentration after maximal exercise was 6.61mmol/1 in 18.0°C, 6.10mmol/l in 22.0°C and 5.36mmol/l in 26.0°C. In 18.0°C of water five subjects drop core temperature (0.2-0.6°C) during 10-16 minutes of exercise.

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A complex work load generator for use in cycle ergometry was computerized in order to obtain information with respect to the interaction of cardiopulmonary variables during exercise and to evaluate muscular work in practical activities. A new constant current circuit was developed to modify changes of both load resistance and internal resistance of alternator, due to the heat accumulation from energy discharge. Prior to the circuit design, the alternator output voltage, field current and the internal resistance were determined. The electric circuit was designed for both manual and computer operation, distributing the load watts to 8 channel load resistors which were arranged for binary output of computer. The TTL circuit selects the signal data of work load instruction and transfer them into each load channel. An ergometer controller data acquisition program was developed to determine the load level and program complex variation of work loads such as ramp, impulse, sinusoidal and random work load. Some applications of the ergometer system are reported and discussed for the analysis of complex physiological systems during work. obtained by both constant and progressive loads

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The objective of this investigation is to clarify the characteristics of the food habits or dietary patterns of the aged, which were summerized, from our survey conducted on the urban inhabit-ants, as distinctly different from the other age groups.

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It has been demonstrated that the functional capacity of cardiorespiratory system af maximal exercise declines with aging (Hossack and Bruce, 1982). Recently deVries et al. (1982) showed the close similarity in physiological responses to sub-maximal exercise in old and young men of equivalent fitness. The present study investigates the effect of age on physical work capacity by comparing oxygen uptake and heart rate at sub-rhaximal exercise between middle-aged women and young women.

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The purpose of this pilot study has been to get an approximate comparison of the capacity of cardiovascular function between young and middle-aged females. The value of maximal oxygen intake per unit of lean body mass was used as the index of the capacity after the recommendation by Buskirk and Taylor (1957).

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Experimental studies on thermal comfort have been made extensively under the standardized clothing. However in actual daily living, we change the clothes according to our thermal sensations (Yoshida, 1983). This study examined the relation-ships between clothes which were chosen by each subject and thermal sensations at rest and during sedentary and muscular works in winter and summer: The differences of optimum temperature between sexes and between age groups have been also reported previously (Miura, 1968;Tochihara et al. 1981). Therefore, in this study, young and middle aged males and females were served as subjects.

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The body composition of the human body has physiological and medical importance. Primary among the parameters of the body composition are lean body mass (LBM) and relative fat content (Fat%). LBM is one of the indices of degrees of muscular development. Fat% is closely related with nutritive conditions, and it may influence mor-bidity and mortality. Although the body composi-tions on males have been measured frequently, the datas on aged persons are scancy. Hence, the present study was undertaken to measure the body composition on males from 20 to 66 years of age.

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Standing ability seems to be one of the functions which show the most distinct decline in the process of aging. Yamamoto (1979) suggested that postural sway in natural standing increases after the age of fifties especially when eyes are closed. A steep decline by age is shown of the ability to sustain standing on one foot and with eyes closed (Meshizuka et al. 1975). There is thus possibility that such severe condition reveals some changes with age in the postural control system which do not appear in normal conditions. Many studies have been made on postural sway by means of spectral analysis (Taguchi, 1978, Chiwata, 1976, Sato, 1977). Frequency components of postural sway in normal subjects may give some information about changes in postural mechanisms by aging especially for one foot and closed eyes condition. This report deals with technical aspects of spectral analysis of postural sway in such conditions.

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Most of studies on circulatory functions of man have been conducted on yourig subjects, usually under 30 years of age. Therefore, there were few knowledges on the effects of aging on circulatory responses to submaximal exercise. The purpose of this study was to compare the cardiac output during submaximal exercise in young adults and middle-aged adults under the different ambient temperature conditions.

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It has been well established by many authers that sound stimuli produce vasoconstriction of peripheral blood vessels. Intensity of the vasocon-striction response depend upon the sound level (Jansen and Rey, 1962, Fucks-Schmuck and Simon, 1969). The response has been observed mostly by a plethysmography. It was reported that the response occures independent of annoyance or any other mental states (Osada et al., 1977). But it is not clear a relation between the response and the age of subjects. The purpose of this study has been to get a relationship between the peripheral vasoconstriction produced by the noise and age in adults.

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