Myths are important in the study of Japanese martial arts, such as today's martial arts, the modern military arts on which today's martial arts are based, and military arts in the medieval age. It is rather interesting to note that Japanese myths were discussed in the literature of military arts throughout every period. This is because Japanese myths have a certain kind of power.
The Japanese mentality was originally controlled by mythical concepts. The mentality of military arts, which plays an important role in the history of the Japanese mentality, is more or less affected by the unaccountable power of Japanese myths. The main theme of this paper is the issue of military arts in Japanese myths.
I have so far clarified the following points:
1. The magical power of the sword as Hekija (exorcising evil gods and demons),2. Relation between the sword and gods (when discussing the magical power of the sword, the sword must be sacred; this is the basis of why the sword is sacred. ),3. The attribute of the sword that connects the celestial world of the gods and the terrestrial world of human beings. (This provides an assumption for the relation between the sword and the gods.)
Likewise, the magical power of the bow and arrow as Hekija, relation between gods and the bow and arrow, and the bow and arrow's attribute connecting between the celestial world of the gods and the terrestrial world of human beings.
For the bow and arrow, the magical power of Seisei was found in addition to that of Hekija. Based on the above research findings, I set the following subjects for this paper:
1. Is there anything other than the bow and arrow that has the magical power of Seises?
2. If there is anything, what is it?
3. When its magical power of Seisei is clarified, can I find something new if I see the magical power of Hekija again?For the analysis, I selected the myth of Ninuriya, the myth of Kuniumi, the myth of Ukei, the myth of Yamatanoorochi, the myth of the God of Fire, Yamatotakeru's Expedition to the East, the myth of Yominokuni, and the Legend of Jnmu's Expedition to the East.
I obtained the following research results:
1. The magical power of Seisei of the spear and the sword was found in addition to that of the bow and arrow.
2. The magical power of Seisei of these military arts is closely related to water.
3. The magical power of Hekijya involving fire was found in the sword, as well as in the bow and arrow.

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To monitor body temperature while causing minimum interference to kendo practice, we developed a wearable device that records the body temperature every minute for more than a day using a thermistor and a microcomputer chip powered by a commercial battery. The device weighs about 200 g and costs less than 5,000 yen. The performance of the device was tested by measuring the temperature of water and by actual body-temperature measurements taken during kendo practice sessions and during long distance running. The water temperature measured with the device linearly correlated with the temperature recorded using an alcohol thermometer. The transient response of the thermosensor of the device against a stepwise increase in temperatures ranging from ambient temperature to 37°C was fast enough for almost undistorted temperature recording. From the fluctuation of the measured water temperature, the device was found to have a temperature resolution of 0.05°C. In a field test of the device during kendo practice by four members of a university kendo club, their body temperatures increased by a little more than 1°C, indicating that there was no risk of heat shock despite the body armor worn, that might prevent efficient sweat evaporation. A characteristic pattern of body temperature change during kendo practice was found in the kendo club members as well as in a middle-aged kendo practitioner: The kendo practice sessions induced characteristic spindle-shaped temperature changes that ascended and descended at a similar rate, independent of the age and skill of the practitioners. The rate of temperature rise was significantly slower than that induced by long distance running as recorded in three members of a university athletic club. During long distance events, body temperature monotonically rose until the end of the run at a faster rate in the middle-aged kendo practitioner than in the athletic club members. These results indicated that our newly developed wearable temperature monitor is sufficiently accurate in recording body temperature at 0.05°C resolution, and the device is useful to monitor individual body temperature response to avoid heat stroke during kendo practice, and hopefully to evaluate the intensity of physical exercise for individuals of various skill and fitness levels.

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This paper describes the simple and safe fixation method of a Judo tatami on a gymnasium floor, regardless of the floor's size. A gym is frequently used for Judo competition and practice. Through a simple process, this fixed equipment unit, named Tome-Taro, can set up tatami that precisely corresponds to the size and shape of a gymnasium floor. Experimental results at a Judo competition and training camp revealed that all tatami could be installed and securely fixed in place during only a week's time. In addition, the gym's floor surface suffered no damage during the tatami's installation, because the Tome-Taro fixation unit is made of foam urethane, which will also improve the safety of the Judo competitors. This fixed equipment unit is registered by intellectual property rights (copyright No.230467) and utility model (No.3138192). It is being commercially marketed by the Ishii Chemical Industry Co., Ltd. as the simple Judo tatami installation unit “Dobashi's Tome-Taro”.

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