The present study examined the presence of bilateral control mechanism generated by both neurological and cognitive interaction reported by earlier studies. The experiment was conducted to measure grip force of each hand during coordinated bimanual arm movement that hold aloft a test object with one hand, that transport and put loads on the test object with the other hand. A total of five healthy subject (4 right-handed, 1 left-handed) was participated in the study. Grip forces applied to the test object and load object were measured. The process of the movement was divided into four phases; preparation phase, transition phase, transportation phase, and loading phase. First, the subjects held aloft the test object with one hand, while the load at the ground was held during transition phase. It was examined that the presence of bilateral control mechanism generated by neurological interaction such that the force on the other hand was co-generated so as to assimilate the force on the loaded hand in this phase. However, the experiment showed that no effects by neurologically originated control mechanism were found. Second, the subjects transported and put loads on the test object held aloft during transportation phase. It was examined that the presence of bilateral control mechanism generated by cognitive interaction was observed. In conclusion, preparatory grip force increment was produced and it was in proportion to the load held.

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As a protective clothing for fire fighting which correspond to flames and a radiant heat is an air tight cloth, it is important to give off metabolic heat of the human body. So, we tried to examine the effect of head cooling for heat stress of fire-fighter in this study. The experiment were conducted under two conditions: ventilation with small ventilators and with coolants. The subjects were four healthy males. The skin temperature was calculated on 7 points of Hady & DuBois method. The skin temperature of neck, back thigh and the temperature within clothes, inside a helmet and external ear temperature were also measured in this study. The experiment was composed of the rest for 5 minutes, the exrcise of coresponding to 120 W/m^2 for 20 minutes and the rest for 5 minutes in the climatic chamber of temperature 30.0 ± 0.5 ℃, relative humidity of 50 ± 3%. The result were following: 1) The external ear temperature with head cooling was lower than that without head cooling. 2) The head cooling with small ventilator is more useful than head cooling with coolant.

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The relations between H reflex and relative EMG power in low frequencies were studied to know the influence of La afferent on the compression of a surface EMG spectrum toward lower frequencies (EMG slowing). The relations were investigated in soleus during a fatiguing contraction without ischemia and during non-fatiguing contractions with ischemia. The changes of EMG spectrum could be related with the changes of H reflex only in two of seven subjects. Ia afferent was not concluded to be the main cause of the EMG slowing. The mechanism that causes the alternation of motor units activity was related with the EMG slowing.

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The 'virtual body fat' approach, which is proposed by the authors, is applied in the present research to clarify effects of fat in all body and each physical part on physical activity. Some loads are attached to each physical part of 10 subjects as the virtual body fat in the experiments, and the effects of the virtual body fat on their records of two sport tests, i.e. 50 m run and vertical jump, are investigated. Furthermore, standard distribution of body fat to each physical part is evaluated by measuring the distributions for 33 subjects, and effects of standardly distributed virtual body fat on the records are clarified quantitatively as well. The fat contained in an abdomen, which is standardly 73.9% of the total fat, has the largest effects on the records. On the other hand, the fat in arms and legs has 1.2 to 3.6 times larger effects than that in the abdomen on the records if the effects of the same weight of fat are compared.

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We have previously showed regional differences in biochemical measurements such as a higher % body fat (%Fat) in S-group (subjects residing in Shimane Prefecture) and a higher insulin resistance (IR) in T-group (subjects residing in Tokyo). In the present study we investigated regional differences in dietary preferences, life styles and psychological factors among the same age young women S-group and T-group, respectively. The main results were as follows: dietary preferences, life-styles and personalities showed regional differences. Some of the measures correlated with %Fat in S-group and with IR in T-group, respectively, and only "depressive affect" was common to both groups. Thus the features of findings obtained in S-group were similar to those that hitherto have shown in the obese. Those in T-group suggested a possible relationship between health and urbanization.

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