A total of fourteen hundred individuals of two local populations living in Toshi-jima Island, Mie Prefecture, have been investigated for genetic variations in blood groups, two serum proteins and twelve red cell enzyme systems, namely, ABO; Hp, Tf; AcP, PGM, GPT, PGD, EsD, ADA, PHI, GOT, LDH, PGK, AK and PepA.
The results showed a remarkable difference between two populations. Also comparisons were made with the results obtained for the neighbouring populations in Kamishima (Toyomasu et al, 1977) and mainland of Mie Prefecture.

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An observation on standing ability of humans were done on the basis of data obtained from the measurements of contact surface of feet soles (CSFS) and electrogravitiogram (EGG), utilizing Pedoscope and Gravicorder. Subjects who took part in the measurements were all Japanese including 4790 males and females.
Results examined were concluded as follows;
1. It might be possible to make observations on standing ability in the following three periods;
1) period of growth...a man of 0-19 years of age. 2) period of maturation...a man of 20-49 years of age. 3) period of declination...a man of over 50 years of age.
2. It was found that the laterality should play an important role in standing ability. This means that standing posture of humans is well maintained by support of the left foot with supplementary function of the right foot.
3. It was proved that there was significant difference between male and female in standing ability.
4. The placement of center of gravity when standing on both feet showed the tendency of shifting forward with advance in age. In case of normal adults at all ages it was placed at 47% from heel regarding foot length as 100%.
5. There found regional differences among subjects in standing ability, which might be supposed to caused by some influences of life-environment upon individuals.

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We measured in this study the angle of the forced leaning posture of a human body, and investigated the relation between its angle and the capacity of a human body to maintain the erect posture which is his basic one.
On analysis of CSFS in he cases of an "active" and a "passive" leaning posture, it gave the following results. ['CSFS' is short for 'contact surface of a foot sole'.]
1. The degree of restoration in CSFS when resuming the previous erect posture is considered to be an important criterion in measuring the ability to stand upright.
2. Both in "active" and "passive" conditions, the fructurations are most remarkable in toes and the central part of the sole, so it is presumed that those parts are functioning dynamically as a factor of adjustment.
3. Comparing "active" and "passive" conditions, CSFS is mostly larger in "active" than in "passive" conditions.
4. When the subject leans forward and backward to the utmost, both in "active" and "passive" conditions, CSFS is remarkable difference between right and left, so laterality can be recognized in this case.

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The sway of the center of gravity and that of the various parts of human body were measured by use of Gravicorder and TV-Tracker about a healthy male. To find out crosscorrelation and phase deff erence of f regencies, the both sways were analyzed with a spectral analysis. Results on the subject are as follows;
1) It was found that there was component of the f regency of approximate 0, 2 Hz in each sway.
2) The components of the both sways had positive cross-correlations each other, and they had phase differences at several points of the body.
3) In the both Ant.-Post. directional sways, power of this freqency had a tendency of decrease when it was tested with eyes closed.

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The movement of the point of the gravity (Electrogravitiogram, EGG) on both feet for 20 seconds of 1738 boys and girls was measured by a gravicorder (Anima Type G 1800) at the health examination for 3 year old children (at M-Health Center) in Nagoya City in November 1977 to in October 1978,
The results obtained in the study are as follows;
1) The percentage of achievement on the test is higher in girls than in boys.
2) The average area of EGG for boys are 16.2cm²(eyer open) and 25.8cm²(eyes closed), and that for girls are 15.3cm²(eyes open) and 21.2cm²(eyes closed). The average length of EGG for boys are 52.8cm(eyes open) and 83.7cm(eyes closed), and that for girls are 51.5cm(eyes open) and 71.0cm(eyes closed).
There was significant defference between boys and girls both in the area and the length of EGG.
3) Almost every area and length of EGG scattered along the logarithmic normal curve.
4) The area and length of EGG were increased by eyes closure in all children. The area of EGG at eyes closed status is 1.7 times as wide as that of eyes open status. The length of EGG at eyes closed status is 1.5 times as long as that eyes open status.

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Six adult males and thirteen adult females were used as subjects, and activities of thigh and leg muscles were recorded on electromyogram, while subjects performed horizontal sway (forward, backward, leftward or rightward) or rotation (left or right) and vertical postural change (half-rising, squatting or standing on tip-toe) and also they took weights (6kg x 2) by hands or were given horizontal push force on chest, on back or on a shoulder.
Human erect posture is maintained mainly by correcting small postural sways. This correction is made by activities of muscles, but two effects (1) restoration of the inclined body to erect position by increasing the opposing muscle activity, and (2) fixation of the erect posture by the joint fixation increasing the activities of both extensor and flexor, exist in the muscle activity patterns. Thus muscles or muscle activities acting on maintaining erect posture are better expressed by saying "anti-sway muscles" or "anti-sway activities" than by saying "anti-gravity muscles" or "anti-gravity activities".

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Position of the line of gravity of the body, electromyograms of the leg muscles, heart rate and tracking errors were recorded continuously during thirty minutes' pursuit tracking while standing without shifting the foot position in fifteen subjects. Some subjects maintained the line of gravity near a central position over the feet, while some subjects showed shifting of the line of gravity to one foot. The heart rate as a whole increased over time, and this tendency was marked for the subjects who showed little change in the position of the line of gravity. When the amount of the excursion of the line of gravity increased, the heart rate kept its level constant or decreased slightly. The relationship between the heart rate and the shifting of the line of gravity was discussed from the viewpoint of the compensatory mechanisms for the disadvantage in the venous return in the erect posture.

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Inspection task whether there is defined two figures of four pieces in two figures of twenty pieces which randomly constructed was repetitively performed by one subject for 60 minutes without sufficient rest pauses. The two figures of twenty pieces were displayed on a graphic display in front of the subject. The subject was instructed that could freely change a standing posture and move his body whenever fatigue set in, and that signed the result of inspection with a switch in his hand. The inspection task was started with a upright standing posture. The switch was then haven in his right hand since he was right-handed.
In the repetitive inspection task, the observation of standing subject was done and the standing postures were sketched. Simultaneously, the time of change of standing posture, of shift of the switch from one hand to the other and of appearance of free physical movements was recorded by means of event markers. Inspection periods were measured by a digital computer.
Seven kinds of standing postures were observed during the 60-min period of repetitive inspection task, three kinds during the 37th minute and four kinds during the period past the 37th minute. The upright standing posture was sustained during the sixth minute of task. Easy standing postures, alternating the supporting leg and straightening arms in vertical direction, were observed from the sixth minute to the 37th minute. Standing postures observed during the latter period past the 37th minute were the other easy standing postures, alternating the supporting the leg and placing one hand without the switch on his waist. The resting leg in all easy standing postures observed during the 60-min period was put in front of the subject, extending his knee joint. The supporting leg was exchanged 9 times during the first 30 min period. The exchange were conducted immediateiy after the subject signed the result of inspection with the switch in his hand. In case of the last 30 min period, the supporting leg was changed 14 times after the sign with the switch and 7 times before the sign. The free leg movements and the free arm movements increased very distinctly from the tenth minute and from the 20th minute, respectively. These movements continued gradually to increase until the termination of task. Their movements were observed while inspecting before the subject signed with the switch. The trunk movements decreased gradually during the inspection task period. The switch was shifted 3 times during the last 30 min period. The shifts of switch were conducted as soon as a new two figures of twenty pieces were displayed on a graphic display. The inspection periods lengthened gradually. The subject lied on the floor, who standed, after the experiment was end, and did not stand up for some time. The analysis of the suck kinds of behavioral "node" formation was suggested as important in discussing the fatigue by the repetitive monotonous work without sufficient rest pauses.

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In enduring a posture in actual living conditions, spontaneously appearing posture changes are considered to play an important role, In this paper, patterns of subsidiary postural changes while working sustaining a certain posture for hours were discussed by analyzing the factors leading to increase of those changes. During a prolonged experimental work period of numeral inspection that demanded short-term memories, variations in frequency of posture changes were apparently dependent on the day's condition and changes in alertness. The rate of those postural changes which recurred at variable intervals of one to several minutes was revealed to be greatly influenced by when and how long the state of sustained attention was affected. In the case of printing workers working while continuously standing, the patterns of posture changes differed between different types of standing conditions. Postural changes enabling resting of the lower extremities or active muscle groups increased during later hours in the afternoon as a result of compensating fatigue, the leg motion rate being significantly related with the rate of subsidiary upper limb activities, whereas the spontaneous leg motions of workeres inserting work-oriented steppings were less frequent and had no correlation with upper limb motions. Postural changes of sitting key-hoard operators were much less and related with other types of subsidiary behavior. These results indicate that the patterns of postural changes are a function of complex factors of the task performing situation that requires a surtained position, and that changes in the central nervous system and in orienting behavior being relevant to motor control functions should be taken into account. Further studies are needed to elucidate conditions of provoking spontaneous changes in human posture in order to discuss their relevance to the mechanism of sustaining an erect standing or a sitting posture for a long period.

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Effect of posture on the amplitude of respiratory sinus arrhythmia (RSA) at some breathing periods between 4 and 12 sec was studied in standing and supine female students of a physical education college.
Tidal volume increased in accordance with the respiratory period. RSA amplitude, measured as heart period (i. e, pulse interval) change, was greater in supine position than in standing posture when the respiration period was rather short, that is at 4, 6 and 8 sec. When the interval change was expressed as percent of existing mean heart period, the difference was significant only at breathing period of 4 sec. RSA amplitude expressed as heart rate change (beats/min) was greater in supine than in upright position at respiration period of 4 sec, but at 10 and 12 sec period the relation was reversed. The greater heart rate amplitude in standing posture at slower (and deeper) respiration seems to be partly apparent, because at shorter basal heart period (i. e, in standing), a similar change in pulse interval is expressed as larger heart rate change than at longer basal heart period. The regression coefficient of RSA amplitude on tidal volume was slightly greater in standing than in supine posture.
This difference in the slope of regression line would explain, also partly, the absence of RSA amplitude difference between the two postures at slower respiration rate.
The difference of heart rate level by posture was negatively correlated with mean RSA amplitude in standing. This seems to come from the fact that the difference is determined mainly by the heart rate level in standing, and RSA amplitude changes as a function of the mean heart period.
Although these results are almost in agreement with the relation of RSA with vagal activity shown by Katona et al. (1975), other factors, like the sympathetic influence on baroreflex sensitivity suggested by Eckberg et al. (1976), should be considered.

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Twenty four young female and male subjects, twelve in each, all in good physical conditions, volunteered for this study. Examinations were made during the following ten basic postures: lying awake, sitting with crossed legs on the floor, sitting on a chair, squatting with hands on knees, bending with trunk forward from standing posture, standing at ease, standing with attention, half rising posture with knees nearly extended, half rising posture with knees bending at 120° and 90°. The measurements were performed at the air temperature conditions of 20°C, 30°C and 40°C in a climatic chamber. The relative humidity and air velocity were maintained at 50% and 18 cm/sec, respectively, throughout all the air temperature conditions.
In all the temperature conditions the lying posture gave the smallest oxygen intake and the lowest heart rate and the half rising posture with knees deeply bent the largest values for both parameters. The smaller intraclass correlation coefficients for heart rate in both sexes and three temperature conditions and the smaller coeficients in females for both items indecate obviously the relatively larger variations within each posture for heart rate than for oxygen intake and the relatively larger variations in females than in males.
The pooled variance for 60 groups classified by the posture, air temperature, and sex was devided into the variances for the factor of posture, that of air temperature in the same posture, that of sex in the same temperature in the same posture, and that of subject in the same sex in the same temperature in the same posture. The result shows that the differences in the means of both parameters between postures were statistically significant and the sex difference in both parameters was highly significant in the same temperature in the same posture. The temperature effect was insignificant for oxygen intake, though it was significant for heart rate.
The analysis of covariance indicates that sex difference in the regression coefficients was statistically significant only in the case of 20°C. The rank correlation between the adjusted heart rate by the differences in oxygen intake and projected height of each posture was confirmed to be highly significant in all the temperature conditions. A certain increment of skin blood flow, the hemodynamics effect associated with redistribution of blood, and the static property of keeping a posture are suggested to be responsible for the above tendencies. Although the sex difference in the regression coefficients disappeared in 30°C and 40°C, physiological strain for keeping a standing posture including half rising one was estimated to be remarkably severe in females.

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Cardiac output during rest in seven postures was determined by a CO₂ rebreathing method in 12 male students under the air temperature conditions of 20°C, 30°C, and 40°C. The mixed venous C0₂ pressure was calculated from the rise of the CO₂ percent in a rubber bag during rebreathing. Arterial C0₂ pressure was assumed to be the same as in end-tidal air. CO₂ output was measured by the Douglas bag technique. Fick's equation was used for calculation of the cardiac output.
The factor of posture produced a significant effect on cardiac output. The significant correlation coefficients between cardiac output and O₂ uptake in each posture indicated a close relationship between them. The regression equations of cardiac output on O₂ uptake throughout all seven postures were calculated in each air temperature condition, and then the cardiac output for each posture was adjusted by the differences in O₂ uptake along the regression equations. Generally, the postures with higher projected height were shown to have lower adjusted cardiac output. However, half rising posture, which has the highest projected height but one, was shown to have fairly high adjusted cardiac output. It was indicated that a gravitational shift in blood volume to the legs was counteracted by the contraction of lower limb muscles in half rising posture. The factor of air temperature showed no significant influence on the regression of cardiac output on O₂ uptake. The prediction equations for cardiac output during rest in each seven posture from air temperature, body weight, height, heart rate, and O₂ uptake were calculated by the multiple regression analysis. The factor of posture produced significant effects on the constants and the partial correlation coefficients of the multiple regression equations of cardiac output. In addition to the above-mentioned five variables, the value of cardiac output during keeping any one of lying, sitting or standing posture was used to make the different type of prediction equations for cardiac output in each of the seven postures. High multiple correlation coefficients and significant F ratio indicated the validity of these equations.

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The urinary characteristics studied comprise flow rate, specific gravity, pH, temperature and excretion rate of five kinds of corticoids. Factorial experiments were conducted on the analysis of those variations, with three factors, each at two levels: upright and recumbent position, day and night, and rest and exercise. The significant reduction for urine flow rate occurred in upright position and by night. In the same manner, the following treatments produced significant effects on some of the urine characteristics: posture, interaction between posture and exercise and interaction between circadian variation and exercise on pH, circadian variation on temperature, circadian variation and interaction between posture and exercise on some corticoid excretion rates. The blood pooling in lower limbs in upright position and circadian mechanisms were suggested as causes of the phenomena.

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Various diseases are being discovered from the abnormal movements caused by the disturbances of the extrapyramidal tract.
The Parkinson disease which is the representative disease of equilibrium dysfunctions is noted with a specific posture reflex disturbance. In gait disturbance, especially, the patient has frozen gait and phenomenon is considered to be due to the rigidity of the muscles caused by tremors.
Recentiy, by using the gravicorder, we had examined and analysed the body sway in the static phase. When observing the patient who had Parkinson disease by means of the gravigram, tremors of 6-7Hz were being recorded on the power spectrum. These tremors which originally appeared on the upper limbs could also be recorded on the standing gravigram indicating that the lower limbs could be influenced by the tremors.
In this research, we experimented with gravigram through quantitative change of muscular stimulations by introducing the galvanic stimuiation that cause frozen gait in Parkinsonism to normal subjects. The experiment was motivated by the fact that the pheemonena of tremors in Parkinson disease were often being temporarily improved with acupuncture, and, we were trying to find out on what frequency of stimulation, the voluntary movements of the muscles in normal subjects could be blocked through muscular stimulations.
As a basic experiment, the muscular stimulation was given at "Shozan" (the inferior surface of the tendon muscle in the leg, International No. BL57) in the normal subjects and recorded the tonic contraction responding to the poulse of galvanic stimulation on the gravigram.
In the patients with Parkinson disease more tonic contractions were being observed in the lower limbs. In normal subjects, stimulations to N. Tibialis on the (posterior lateral) lateroposterior surface of the knee with plate electrode produced simultaneous galvanic stimulations to the muscles of both lower limbs.
The pulse stimulations of 5 mA were being used in this experiment such as 1Hz, 3Hz, 5 Hz, 7Hz and 10Hz, and they were being administered to 5 normal male subjects at 30° fan-shaped foot position. It was found that under the stimulation of 1Hz-5Hz, the equilibrim righting function of voluntary movement did not disappear, however, its function could be blocked with 5Hz-7Hz. By 10Hz stimulation, the voluntary movement was blocked by complete muscular contraction and the body position assumed the defence posture.
The frozen gait phenomenon in Parkinson disease is considered to be the result of the blocking of the voluntary movement and in fact, patient, with Parkinsonism have poor motor coordination of swinging movements from left to right and from front to back.
As regarding the effect of acupuncture, we have analysed the data of cases with Parkinson disease and found out that the tremors appeared through the dysfunction of extrapyramidal tract caused by the disturbances of the pallidum and strictum.
Acupuncture produces muscular contractions by peripheral pulse stimulation and the extrapyramidal tract which is related to other movement reflexes transmits a strong feed back against this stimulation resulting in the disappearance of the tremors.

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