Seasonal variation of basal metabolism was measured on seven young male (the Ground Self-Defence Force Officials) aged 19-26 for twelve months (from March 1983 through February 1984) at the Beppu Post in Oita. The results are as follows:
The basal metabolism fluctuates like sine curve. The highest value (5.2% higher than the annual mean) is obtained in April and the lowest (5.8% lower) is in October. Therefore, the annual deviation in the basal metabolism was 11.0% from the annual mean. The annual mean basal metabolism corrected to twenties, is 39.9 kcal/m²/hr, and this value is 6.6% higher than the reference value (37.5 kcal/m²/hr) . In Japanese, it has been accepted that basal metabolism is lower in summer and higher in winter, and the reasons of the seasonal variation are explained by the wide range of the temperature throughout the year, and by the lower ratio in fat intake. Our results generally agree them.

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Twelve male non-athletic and 93 male athletic university students (16 volleyball players, 15 basketball players, 11 long-distance runners, 10 baseball players, 10 table tennis players, 8 throwers, 10 rugby football players, 5 weight lifters and 8 practitioners of martial arts) were selected as subjects. Experiments were performed at 1500 hours in winter. Each subject took a rest on a chair for 30 min at a room temperature of 22°C, after which the subject exposed his left hand distal to the wrist to cold air at -10°C for 30 min. The skin temperature at the central part of the dorsal surface of the distal phalanx of the left middle finger was recorded continuously from 5 min before cold exposure, to 50 min after the beginning of exposure. The results obtained indicated that the higher the skin temperature of the finger before cold exposure, the shorter were the times for the first temperature rise and recovery, and the higher were the initial temperature rise and the mean skin temperature during cold exposure. The mean skin temperature tended to be lower in subjects with longer finger length. The mean skin temperature of long-distance runners, throwers and rugby football players tended to be higher in spite of a lower skin temperature of the finger before cold exposure. Practitioners of martial arts showed the lowest mean skin temperature. Volleyball players showed a lower mean skin temperature despite having a higher finger skin temperature before cold exposure when compared with nonathletes.

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Seasonal variations in occurrences of obstetric complications were examined among 3, 220 case records of singleton deliveries with 24 or more gestational weeks during the period between 1972 and 1980 in Teikyo University Hospital, Tokyo. The pre-term and post-term deliveries occurred more frequently (not significant) in summer (June-July) and in winter-spring (January and April), respectively. Monthly incidences of weak pains (lower in May-September) and related complications such as premature rupture of the membranes (higher in July-November) and meconium stained amniotic fluid (MSAF) (higher in February-April) showed significant seasonal variations. Among the seasonality of other complications, the frequency of postpartum hemorrhage (lower in August-December) and entanglement of the umbilical cord (EUC) (higher in April-October) showed significant seasonality.
As for the seasonality of mother's own birth, those born in March July were complicated more frequently with the post-term delivery. Mothers born in summer showed a lower frequency of weak pains and related complications such as prolonged labor, premature rupture of the membranes and MSAF. Among other complications, the lower frequency was not observed in summer-born mothers except in the frequency of postpartum hemorrhage. The frequency of EUC was higher in mothers born in October-November. Deliveries without any complication and also without any weak-pains-related complication were higher in mothers born in summer (April-September) .

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As a protective clothing against agricultural chemicals non-permeable materials are used in closed designs. Such clothings give us great physical and mental burdens. To examine the comfortableness of protective clothings experiments were performed with four protective dothings A, B, C and D of different materials or designs and a training wear (TW) .
Five healthy female young adults were exposed to 26°C, 50%RH and 0.1 m/s wind in a laboratory. They kept rest on chairs for 10 minutes, then performed an exercise of stepping up and down a 25 cm high platform 30 times/min for 20 minutes and again kept rest on chairs for 30 minutes. Rectal temperature and skin temperatures on nine points, microclimate under the clothing, heart rate, total sweat rate and an amount of absorbed water to clothings were measured. The subjects described their feeling of warmth, discomfort, wetness and wearing of clothings before, during and after the experiment by rating scales.
Mean skin temperature showed a maximum at five minutes of exercise. The maximal change of the skin temperature was larger in the order TW < C <A ≅ B < D. Total sweat rate was not different between the four protective clothings, but the absorbed water to a clothing was larger in the order TW < C < B ≅ A < D. Therefore, protective clothing C with a high moisture permeability was the most effective one. The heart rate showed a maximum at the end of exercise and could not recover perfectly at the end of the experiment with little difference between the four protective clothings. The recovery from discomfort feeling was better with protective clothing C or TW while it was the worst with D among the four. As a result, feeling of wearing was the best with TW followed by C, and was the worst with D. The feeling of discomfort or wearing had a high correlation with mean skin temperature, inner humidity or absorbed water to clothing.

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Five healthy male subjects (19-22 years old) were immersed to the neck in ‘Kan-no-Jigoku’ spring water (13°C) for 15 min, twice a day, for consecutive 12 days. Venous blood samples for the measurements of glucose, free fatty acids (FFA) and insulin were drawn before and after the 1st, 7th, 13th, 19th and 23rd immersions. At the 1st immersion, no acute response in blood glucose to the cold-water stimulus was observed. However, blood glucose levels decreased at 15-60 min after each of the 7th to 23rd immersions. FFA levels showed an acute rise after every cold immersion, but the degree of the acute response in FFA gradually decreased during the course of the serial immersions. Basal insulin level tended to increase until the 7th day and to be maintained in a high level thereafter. These results suggest that either the mobilization of glucose and FFA decreased or the utilization of those substrates increased by the repeated cold-water immersions.

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In order to assess the effects of acute hypobaric hypoxia on the cardiac pump function at supine rest and during supine submaximal pedaling work, non-invasive methods of the systolic time intervals (STI's) and impedance cardiography were applied. The experimental conditions were a control (SL: sea level), 4, 000 m, 5, 000 m and 6, 000 m simulated altitudes. Five healthy males were participated as the subjects. The following results were obtained.
I) At supine rest; (1) Although heart rate (HR) increased significantly at over 4, 000 m compared to that of SL, no significant change in cardiac output (Q) and stroke volume (SV) was observed. (2) The QS₂ (total electromechanical systole) and LVET (left ventricular ejection time) significantly decreased at over 4, 000 m. (3) The PEP/LVET ratio decreased with increase of altitudes, and was significant at 6, 000 m compared to that of SL.
II) Submaximal work; (1) Although HR increased linearly with the increment of work load, HR during the work under simulated altitudes was always significantly higher than that of SL. However, no significant difference in SV and Q was observed although SV during work under hypoxia showed always lower values than that of SL. (2) The QS₂, LVET and PEP progressively decreased from SL to 75 watt of work in each altitude. These changes except PEP at 75 watt of work were significant at over 4, 000 m compared to those at SL. (3) Although the PEP/LVET ratio at each altitude except 6, 000 m decreased from rest to 50 watt of work, it tended to increase at 75 watt of work. From the results described above, it might be concluded that (1) the left ventricular function at supine rest is enhanced by the acute hypobaric hypoxia, (2) the myocardial contractility is enhanced until the light work and then tends to be deteriorated at more heavier work under acute hypobaric hypoxia.

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