Although the control of breathing during exercise has been studied extensively that both neural and humoral factors may play a role in mediating the exercise hyperpnea, it remalns unresolved whether the response is due solely to neural or humoral mechanisms and how the pulmonary gas exchange matches to the tissue exchange rates. At just onset of exercise ventilation can increase abruptly within I to 2 breathes (Phase I). Such a rapid increment of ventilation is not attributed to the humoral factor(s) due to the circulation delay from muscle metabolites.

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The thickness of subcutaneous fat were measured at 215 different points on the trunk in Japanese young women wlth using B-mode ultrasonic device. Subjects were 10 healthy Japanese females aged from 20 to 24 years. Average subcutaneous fat thickness over the trunk of 10 subjects was 9.8 mm, and it's standard deviation was 1.5 mm. Subcutaneous fat thickness showed the higher value at the buttock, the breasts and the abdomen and the lower value at the back. The difference of fat distribution between obese subjects and lean subjects was exhibited mainly on the abdominal parts but not on the chest and back parts of the trunk.

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Warming up procedures in the many antecedent reports, are almost under normal ambient temperature and they do not treat the warming up under low temperature. The purpose of this study was to investigate the effects of warming up by intensity and time in submaximal treadmill exercise (90 % VO₂max intensity during 10 minutes) on physiological parameters under cold environment in climate chamber (room temperature : 10°C, relative humidity : 70 %, wind velocity : under 0.2 m/sec). Eight traind collegiate basic skiers performed main exercise for 5 minutes after the follow-ing warmlng up conditions: Now-up (no warming up), W50-15 (50% VO₂max intensity 15 minutes). W70-15(70 % VO₂max intensity 15 minutes), W50-30(50 % VO₂max intensity 30 minutes) or W70-30(70 % VO₂max intensity 30 minutes). It was concluded that the most effective intensity and time of warming up in these conditions were 50 % VO₂max intensity and 30 minutes duration, that is, rather low intensity and longer duration time. It was suggested that a warming up with a high intensity and short duration was effectless under cold.

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This study was undertaken to evaluate the effects of the asymmetric radiation on thermal comfort, and to suggest the optimum comfort limits in a radiant heating space. The index of V.R.T. (Vector Radiant Temperature) was used to describe the environmental quality of the heated floor space. Optimum comfort limits of this space were suggested through both theoretical and empirical studies. It is recommended to use not only man's sensation of the ambient air but also that of the floor surface for the determination of the optimum comfort limits on the heated floor space such as an "Ondol" in Korea. In the present study the optimum comfort limits were suggested in terms of the V.R.T.. The optimum limits obtained were as follows : - the vector radiant temperature 11.0-15.0 K.

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In the present study, we investigated the correlation between the physiological function, heart rate (HR) and the quantity of work performed when A-weighted sound pressure level of factory noise or construction noise was varied during the mental operations of calculation and erasion. Furthermore, we looked for differences in the effects of sound noise and music on the quantity of work performed. The A-weighted sound pressure level was set at four levels of background noise, i. e. 60, 70 and 80 dB (A). The music sound level was set at 70 dB (A). The subjects were exposed to factory nolse, construction noise and music during their mental work. A balanced factorial experiment was conducted with a total of 16 combinations of types of mental work (two levels of calculation and erasion), sound noise (two levels of factory and construction sound noise), and A-weighted sound pressure levels (four levels). The order of the experimental procedures was determined at random. The following conclusions were made from the findings of the study.

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The present study was designed to investigate the effects of color temperature of lighting sources on the heart rate variabiiity. Eight male students volunteered as subjects. The heart rate variability during task and rest sessions were estimated under nine different lighting environments consisting of three levels of color temperature (3000°K, 5000°K and 6700°K) and three levels of illuminance (1001x, 3001x and 9001x). The lighting condition caused no effect on the mean heart rate. On the other hand, the power spectrum of heart rate was significantly influenced by the lighting conditions. The respiratory sinus arrhythmia component and Mayer wave related sinus arrhythmia component of the power spectrum increased under higher color temperature conditions. Judging from the consistency of heart rate level, the balance between the effects of parasym-pathetic and sympathetic nervous systems remained at a constant level irrespective of lighting quality and intensity. Therefore, both parasympathetlc and sympathetic nervous functions were concluded to be enhanced under higher color temperature conditions. The light with higher color temperature was considered to activate the autonomic nervous function more than the light of lower color temperature. The effect of color temperature was much remarkable in the rest session comparing with the task session. This fact was discussed from the viewpoint of color temperature effect in environmental lighting.

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The purpose of the present study was to assess the validity of Piezo-electric accelerometer for estimating energy expenditure in walking and jogging. Energy consumption by oxygen uptake was determined during steady state level of treadmill walking at the speed of 60, 80 and 100 m/min and jogging at the speed of 100, 120, 140, and 160 m/min for 10 subjects. There was a highly significant correlation between the energy consumption and the estimated energy expenditure by an accelerometer despite the attached position (r = 0.912 at the waist, r = 0.915 at the chest, P<0.001), which suggests accurate estimating energy expenditure in the field.

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