Institute of Population Problems, Health and Welfare Ministry The population problems are the research theme from ancient times to present times and also towards future times. Accordingly in order to be fruitful to this research, we must develop new idea by an integrated study not only from the viewpoint of socio-economic field but also political and cultural field. Population statistics are one of the data, but now this technic rather preferentially is studied. Therefore the research of population theory or population philosophy etc. which show the important study as population problems, become to be made light. However as shown in Japanese population trend after war, such rapid population changes which mean that birth rate and death rate became half within ten years, could not be realised through the line of old population theory. Then centering around the demographic tendency in Japan, I summarise these population problems as follows.
1) What are problems until the reach to the stabilization of population,
2) Leveling up the population quality in future,
3) Regional and occupational population problems,
4) Problems of relation between population and social welfare system,
5) Research project of the magnitude of population quake in future.
Above mentioned 5 subjects must be researched as a population-reseacher, especially the problems of population quake are one of new idea, because as they often say the population explosion, we must explore and analyse the meaning or content of it. Therefore under the background of presumption which something like quake may break up before the explosion. I would like to make a plan of the predicted index to contribute to the better population policy plan. Now many anthropologists begin to research the population problems and increase the power of speech or proposal to this problems especially from the point of cultural field. I would like to point out that one of target of anthropology also should be to resolve the population problems.

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The establishment and development of the science of clothing hygiene in Japan were reviewed, and the researches which had been carried out since World War II were summarized into the following items:
1. Studies on physiological and hygienic significance of the clothing in human body temperature regulation.
1) Skin temperature and the methods of measurements.
2) Clothing climate under comfortable conditions.
3) Thermal insulation properties of clothing and their measurements.
4) Analyses of factors affecting the thermal insulation properties of clothing; functional properties of clothing materials, design, f ittness, number of layers and weights.
2. Studies on the uncomfortable factors caused by clothing.
1) Effects of clothing pressure on human body.
2) Lasion due to physical and chemical features of clothing, especially of newly developed artificial materials.
The University Chartering Standard Committie in 1976 has decided that clothing hygiene should be one of five essential subjects for the clothing science course. Recently, the number of people who are interested in clothing hygiene from other fields such as physical science, technology and physiology has increased, therefore the physiological and hygienic studies of the clothing will develop progressively in the future.

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To examine whether or not the frequency polygons of the standing height in 296, 799 Japanese youth, 6 through 21 year-old boys and girls, are the "bell-shaped" normal curves, the normality-test analysis with reference to k-statistics is carried out on the frequency distributions of the standing height. In this test method, four nonnormal frequency distribution types which deviate from the normal curve are positively and negatively skewed, leptokurtic and platykurtic ones. The purposes of this study were: 1) to recognize what sorts of frequency distribution are contained in the standing height frequency distribution of the Japanese youth groups by the normality-test procedure; 2) to determine which growth curve (distance, velocity or acceleration) is similar to the skewness coefficient curve from 6 to 21 year-old subjects. The conclusions are: 1) the frequency distribution curves of 9 year-old boys and 16, 18, 20 year-old girls show nonskewness and mesokurtic curves; 2) only male senior high school and female junior high school subjects have negatively skewed distributions; 3) almost all Japanese youth groups have leptokurtic distributions, but 13 year-old boys and 11 year-old girls have platykurtic ones; 4) the phenomena of the maximum positive and negative skewness appear at the age of 11.5 and 14 in the male and 9.5 and 12 in the female; 5) the changing phases of skewness coefficient with reference to the ages in both sexes are similar to their own growth acceleration curves.

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Though the pathological changes in bones of the early Japanese people have attracted attention of physical anthropologists for more than half a century, the descriptions of only a few pathological anomalies have been published in various independent reports.
The present study deals with various kinds of pathological changes in vertebral columns. As shown in Table 1, 188 vertebral columns in total from Jomon to Edo periods were observed. Since the skeletal remains from Yayoi to Muromachi periods are in very poor condition, and as many skeletal remains of Edo period were found in group burials, skulls and post-cranial skeletons could not be identified with certainty.
Spondylosis deformans which forms osteophytes in vertebrae was classified according to various types and grade as shown in Figure 1, The incidence of osteophytes in the male of Jomon and Edo periods are given in Table 2.
Regarding the degree of osteophytes, significant statistical differnces were observed between Jomon and Edo people. The former have higher frequencies in grades II, III and N, than the latter. This seems to reflect the difference of the condition of subsistence especially of the intensity of physical working. The highest frequency of osteophytes was seen in the lower thoratic and the lumbal spines, especialy in L-2 and L-3. The degree of osteophytes (grade) changes from grade I to IQ and N with the advance of age.
Lumbo-sacral transitional vertebrae, spina bifida occulta, and Schmorl's node were also observed. The incidences of each type of these malformations in both sexes are given in Tables 3, 4 and 5.
Lumbo-sacral transitional vertebrae was classified into four types set forth by JINNAKA according to the process of articular formation as shown in Figure 2. Spina bifida occulta in the sacrum was classified into two types, complete type and imcomplete type. The former was not recog nized at all in every period. The incidences of the later range from 10% to 13%.
Schmorl's node was found frequently on the lower thoratic and the lumbal vertebral bodies as it was the case with spondylosis deformans.
Other interesting pathological changes in vertebrae diagnosed as spondylitis tuberculosa, spondylarthritis ankylopoetica, vertebral body fracture, congenital intravertebral ankylosis, congenital anomalies, etc., were described. As for the origin of tuberculosis in Japan, this infectious disease is supposed to have been imported from the Asian continent in Yayoi or Kof un period by immigrants who introduced continental culture to this country.

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To estimate the value of physiological load of cycling with special reference to cardiorespiratory responses, oxygen intake, pulmonary ventilation and heart rate was measured directly during seven kinds of bicycle ergometer work in the laboratory, and heart rate during outdoor cycling were also obtained by the telemetry method for seven healthy young males of ages from 19 to 21 years.
physiological load was expressed by % of maximal oxygen intake (% of Vo2 max.). Maximal oxygen intake was directly measured by the Daglas Bag method, and oxygen intake levels were estimated indirectly from heart rate levels during cycling using the regression equations determined for each individual between directly measured oxygen intake and heart rate. Outdoor cycling was made under the following conditions: (a) Twenty-one kinds of conditions which consisted of 5, 10, 15, 20, 25, 30 and 35 km per hour of cycling speed and 1, 67 (40×24), 2.35 (40×17), 3.13 (50×16) gear ratios of pedaling. (b) Long distance cycling tour of about 120 km as a prolonged exercise.
Results obtained were as follows: (1) High significant correlation was obtained between oxygen intake and heart rate for each subject. (2) When cycling speed was increased to 15 km per hour on level ground, physiological load gradually reached the level of 30%Vo₂ max. However, when increased to 30 or 35 km, it was indicated abrupt increase at 80 or 900 level, (3) There was significant different of physiological load among gear ratio of pedaling, (4) In the case of long distance cycling tour, heart rate was changed from 94 to 164 beats per minutes, so that predicted levels of physiological load was between 45 to 75% of Vo₂ max.

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Seven Japanese male adults aged 23-28 were subjected to a cold environmental stress. Three of them were born and grew in Hokkaido district which is a northerland in Japan (HK group), and the other four were born, grew up in Honshu or Kyushu district in Japan and immigrated into Hokkaido (Non-H K group).
Measurements of heart rate (HR) and bipolar surface EMG of 11 muscles were performed before and during exposure to the cold environment which was consisted of the air temperature of about 10°C, the radiant temperature of about 10°C, the relative humidity of about 50% and the air movement 10-20 cm/sec.
In consideration of a large number of other previous papers on H R during cold exposure, it could be supposed that H R might be suppressed by cold stimuli and facilitated by shivering. It seemed to be quite right to consider that increase in H R would be caused in the intense cold environment for individuals as a whole and decrease in the slight cold. Under the above assumption, H R changes of H K group and Non-H K group were discussed. It could be considered that H K group was superior in the cold tolelance to Non-H K group within the limits of the present experiment.
From the EMG results in HK group shiverng occurred mainly in trunk region, and two of Non-H K group had the same result but in the other two of Non-H K group shivering occurred not only in trunk region but also in inferior extremity region. It might be pointed out that in the cold environment when shivering extended to extremity region especially great inferior extremity muscles from trunk region HR increased compared with that in the optimal thermal environment.

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A study of work capacity and physiological responses to endurancework performance was carried out at plains (Chandigarh 750 ft. above sea level) and at higher altitude (Sainj, India 4500 ft. above sea level). Investigations were carried out on members of a field party consisting of 8 individuals (4 males and 4 females) in the age group of 20-25 years. The team members were first examined soon after their arrival at Sain j. The second reading was taken after a stay of about 14-15 days in Sainj, and the third reading was taken after about a month of their return to plains.
The study revealed that cardio-respiratory characteristics are closely related to altitudinal exposure. The principal adaptive responses to hypoxic conditions at higher altitude consisted of increase in pulse rate and decrease in oral temperature and blood pressure (both systolic and diastolic). Vital capacity did not show any adaptive response to altitude at least up to 4500 ft. above sea level. Increase in physical work capacity was observed at higher altitude. Physiological responses to endurance work performance at plains and at higher elevations revealed marked differences.

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The estimated maximal oxygen uptake and some indices of body size and composition, including body height, weight, and skinfold thickness at two sites have been determined on subjects aged 12, 13 and 18, 19 in Fukuoka during step work. Sex difference in maximal oxygen uptake in aged 18, 19 groups and age difference in body fat percent of weight in females were shown significantly. There were different regression equations of maximal oxygen uptake on body weight with respect to the elevations among age, sex, and region. It is considered partly due to difference in effective muscle mass that can be used to perform the work. On the other hand, the same regression line of maximal oxygen uptake on lean body mass were obtained regardless of sex and age, and it was calculated at Y=-0.012+0.055X. As a result, it esems that in relative sedentary residents irrespective of sex, age and region maximal oxygen uptake is related to the volume of lean body mass.

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SATO et al. (1977, 1978) reviewed several methods for estimating human energy cost in field work situations and proposed new predictive equations for adult male and female subjects. The results reported by SATO et al, show that the new equations were more precise than others in estimating oxygen intake (Vo2). This study examined the validity of the new equations when they were applied to younger subjects.
Twenty boys and nineteen girls of Jonan Junior High School served as subjects for this study (Table 1) and took two step tests for six minutes. The rate of stepping work was 15 steps/min for step test I and 30 steps/min for step test II using step height of 30cm. Heart rate (HR), pulmonary ventilation (VE), and oxygen intake were determined during the last two minutes of each of the step tests (Table 2).
In comparing correlation coefficients between observed and predicted Vo₂ and errors in predicting Vo₂ (Table 3 and 4), the predictive equation on VE and the multiple regression on HR and VE resulted in reasonably accurate predictions in this study. Prediction from HR had the lowest values of correlation coefficient. The prediction of Vo₂ by the method proposed by SATO et al, yielded higher correlation between observed and predicted Vo₂, but systematic errors in prediction resulted. The results of this study seem to indicate that with some modifications in constants, there would be a possibility of getting greater accuracy in applying the new equations to such younger subjects as in this study.

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