This report deals with the study of electroencephalograms of 36 subjects who inhaled hypoxic mixture at sea level (Po₂ is as that at 7000m above sea level) or in a hypobaric chamber with rapid decompression (as that at 5000-7500m above sea level) and of 46 subjects who reached high altitude area (5000-8600m) under chronic hypoxia. The characters of the EEGS at rest during photic stimulation, hyperventilation and convalescence after hypoxia were compared in the two experiments. The result of experiments shows that in the same individual, the severer the hypoxia, the more obvious the changes on the EEGs. At the same altitude, acute hypoxia causes more obvious changes on the EEGS than chronic one does, but its speed of recovery is faster than that of chronic hypoxia. Under chronic hypoxia, the changes on the EEGS caused by hyperventilation are slightly less than those under acute hypoxia. When photic stimulation is given, there is temporary appearance of a waves on the EEGS featuring slow waves under acute and chronic hypoxia. The possible mechanism of changes on the EEGS under acute and chronic hypoxia is also analyzed in this report.

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This paper report on the changes of the EEG of human during simulated saturation diving at different depths with different mixture gases. The results of this experiment show that there appears diffusion slow waves (θ and δ waves). The changes of EEG at 50 m depth were more obvious than those at 36.5 m. With the prolonging of time under high pressure, the EEG had some improvements, for instance, the slow waves decreased and α waves increased. There was a certain relationship between these changes and the physiological symptoms. The chief factor of the changes of EEG is nitrogen narcosis for the oxgen-nitrogen diving. In addition, carbon dioxide retention under high pressure is also a factor because Co₂ rebreathing and hyperventilation (i.e. high and low Co₂ in body) aggravated the changes of EEG. The main changes of the EEG during helium-oxygen exposure at 302 m depth were the increase of θ waves and δ waves, the decrease in α rhythm and the decline of amplitude of α waves. Increased θ index and decreased α index could be seen at the depth of 302 m. Under any of the above-mentioned high pressure condition, when slow waves were taken as characters in the background in abnormal changes of the EEG, the EEG could be temporarily improved by photic stimulation, that is slow waves disappeared and α waves reappeared. When photic stimulation was over, α waves disappeared and slow waves reappeared. It was indicated that abnormal changes of the EEG under high pressure were a kind of temporary and reversible changes of the brain function.

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The aerodynamic drag associated with three types of commercially available running apparel (SS : nylon singlet and shorts ; L : nylon/spandex bodysuit and RS : nylon rainsuit) and two bodysuits of newly developed stretchable, water vapour permeable fabrics (T and K) was measured in a wind tunnel on a mannequin at four velocities (4.7, 7.1, 8.8 and 9.7m.sec^-1). The effect of apparel on drafting efficiency was also examined by positioning a human subject on various grid coordinates around the mannequin and alternating the apparel worn by the subject and mannequin. Commercially available running apparel caused consistently higher drag than the T and K bodysuits. Under all conditions the high sheen and tight fit of the K fabric allowed drag reductions of between 17.5 and 7.4% at running speeds. A hood over the hair was responsible for 6 of the 7.4% reduction in drag noted with the K suit. It is estimated that reduction in drag of this degree provide real time savings of between 1.05% in the marathon to 2.75% in the 100m dash. A field trial of the K suit with 16 male subjects (mean age : 22 years) revealed a significant (p≤ .025) decrease in 100m running time amounting to a time saving of 1.17% at a velocity of 7.43m·sec^-1. Results of the drafting investigations suggested that 1.0m is the optimal distance to draft behind a lead runner. At a forward velocity of 7.Im·sec^-1 this practice provided a 62.7% reduction in drag. Further reductions in drag were possible if the following runner was clothed in the K apparel. Practical race strategies are suggested by these results and by the observation that running abreast a lead runner results in a larger shared drag than would be encountered by either runner alone.

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The thermal properties of two types of commercially available running apparel (SS : nylon singlet and shorts ; L :spandex/nylon bodysuit) and two bodysuits of newly developed stretchable, water vapour permeable fabrics (B and K) were investigated under ambient conditions of 0° and 25°C, 50% RH. Six male, middle distance runners performed 30 minute runs on a treadmill at a pace requiring approximately 80% of maximum oxygen uptake against a fan generated wind of 4.2m·sec^-1. Oxygen uptake kinetics, heart rate, sweating rate, core and skin temperature and perceived exertion were recorded. At 25°C, the K suit retained 23.5 and the B suit retained 9.1 times as much sweat as SS apparel (p≤.01). Both suits became intolerable for running in beyond 22 and 25 minutes, respectively (p≤.01) at the designated speed. However, at 0°C, subject tolerance for all apparels exceeded the criterion running time. In the cool condition the comparatively high air permeability of the L suit resulted in a significantly lower core temperature increase (p≤.035), compared with the other apparels. Even in cool conditions, the K suit retained significantly more sweat than the other apparels (p≤.01). However, subjects favoured the K suit over the B suit due to its lighter weight and greater stretchability. In order to maintain efficient thermoregulation during extended wear in the hotter environment, future running suits should be developed from stretchable materials which have better vapour permeability.

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The man has suffered high pressure accidents like oxygen toxicity and nitrogen narcosis under hyperbaric air breathing. Heliox mixture gas (He-o₂) was employed in order to prevent a man from the impairment. The increase of the ambient pressure, however, had influence on various physiological functions. This manuscript reviewed chiefly the study of hyperbaric physiology for heliox gas, that is, (a) high pressure nervous syndrome (HPNS), (b) the effect on respiration, (c) the effect on cardiac function, and (d) the effect on comfortable ambient temperature. The physical feature of inert gas under high pressure was also investigated. As for the countermeasure for HPNS, the following procedures were known : That is, (i) temporary stop at a compression stage, (ii) excursion, (iii) the use of trimix gas (He-O₂-N₂), and (iv) the decrease of compression rate has been studied. The hyperbaric environment denoted the limit of intense physical labour. The cause of bradycardia under hyperbaric environment showed both the dependency of pressure and that of respiration gas (i, e., oxygen, nitrogen and helium). The environment of heliox gas needed high room temperature (32°C The present condition of the limit which mankind reached the deepest sea level was investigated.

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Considering the development in growth, it is not necessarily said that more convenient life is desirable for man. Various motor skills and activities or style of daily living were studied on 186 third- and fifth-grade children at Fukuoka-city by questionnaire. Motor skills examined were using knife, scissors and nail clippers, knotting strings, etc. Quessions on behavior of daily living were concerning kinds of shoes and clothes, tools to sharpen a pencil, assistance in housework, etc. The results were presented in the figures. Although a clear-cut relationship was not observed between the motor skills and behavior of daily living, there is a general tendency that children who used less convenient tools and assisted more housework showed more skills.

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