The purpose of this study is to analyze the changes in the sports industry in Japan, mainly from the viewpoint of family income and expenditure. The market of the sports industry has a deep relation to personal life style, and thus it must be considered from the side of personal demand. Considering today's trends, sports are being played by the old and young, the rich and not rich, and are becoming one of the important factors that make one's life vital and satisfactory. The Sports Quotient, which means the proportion of sports expenditure to household expenditure, clearly shows that sports is becomingg a necessity for people just as eating and sleeping, and that it will play an important role in analyzing people's living standard, in place of Engel's Quotient.

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According to our previous studies, landing shock loads are well identified by using the vscoelastic model with nonlinear unsymmetrical viscosity. Using this model, variability of landing shock loads is represented on the model parameters . To consider the variability in different running velocities, we measured 60 landing shock loads during steady pace running at three different velocities, 3m/s, 4m/s and 5m/s . The results are summarized as follows: (1) a large variability in the model parameters and the force sequence produced by each element was observed in spite of small variability of landing shock loads, but there was also observed an independency between the large variabilities, (2) a large variability of the lower masses and that of the impulse produced by nonlinear unsymmetrical viscosity and a nonlinear elastic element was observed in 3m/s running.

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The mechanical properities of golf clubs are represented mainly by the flex(flexural property)and the torque-degree(torsional property). The initial speeds and the fly-out directions of balls hit by golf clubs with different torque-degree shafts were evaluated using a golf shaft swing machine. It was found that golf clubs with low torque-degree shafts can achieve higher initial speeds and are more stable in the fly-out direction than clubs with high torque-degress shafts. The reasons are as follows.1) The degree of torsion of low torque-degree shafts during the time the golf club head hits(touches)the ball is lower than that of high torque-degree shafts.2) A golf club shaft exhibits torsional vibration behavior during the swing even before the impact point. In the case of low torque-degree shafts, the amplitude of vibration is smaller and the face of the club head returns to a proper angle.

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An inverse analysis program using a sensitivity method has been developed to optimize the natural frequency of golf club shafts. In this program, a composite cylinder which has various diameters and thicknesses laminated in various fiber orientations is modeled by a single beam element to decrease the degrees of freedom of the vibration problems. Therefore, eigenvalues of laminated composite cylinders can be analyzed without influence from the aspect ratio of the element. In the sensitivity analysis, a generalized inverse matrix is utilized. As a numerical example, a CFRP golf club shaft is designed to have higher frequencies in its 2nd and 3rdmodes.

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This investigation suggests a basic plan for construction of a large-scale lowpressure training center, as one of the new utilizations for underground space. In mountain climbing at more than 4, 000 m and in sports which need stamina, such as gymnastics, swimming and skiing, the effectiveness of training in low pressure/low oxygen environments has been recognized, and many athletes have been training at high-altitudes abroad. We investigated the feasibility of using the underground spaces of the National KASUMIGAOKA Sports Stadium and an abandoned mine of KAMIOKA as typical examples of underground spaces that have superior characteristics of airtightness, constant temperature and humidity. Contents of the study are as follows.(1) Investigation about existing examples of underground space utilizaition and the influence that low pressure environment has on the human body(2) Decision on the fundamental concept of low pressure training center(3) Examination of institution constitution, structure, execution method, low pressure system and protection against disasters(4) Examination of systems to create the most suitable environment for trainingcomfortably in underground space

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This paper describes how laser radar can be effectively applied to sports measure ment. Measurement range of running distance was examined under various clothing and speed conditions. The experimental results show that laser radar can be effectively applied to online running distance measurement. As an example, distance from a starting point to the runner in a sprint was measured. Combined with the application using a simple highorder function, measurement enabled the continuous estimation of the velocity and acceleration of the runner. Laser radar has a vast range of application in sports measurement .

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