The turning motion of an alpine snow ski is produced by centripetal force and the moment around the center of mass. Both the force and moment are produced by resistance forces from the surface of the snow. The resistant force of the snow surface is supposed to be mainly composed of two forces. The first one is cutting resistance force, which is used to express the force to cut ice or a snow surface during turning, and the second one is impact resistance force, which is used for the force due to the relative change in momentum of the flow of fractured snow. Using compact snow, we measure three-dimensional compact snow cutting forces, apply multiple regression analysis to determine empirical equations of these forces, and then use the resultant equations to simulate the turning motion of skis. The equations of motion of the system including these forces are solved numerically, and we can find the position and the direction of a ski-skier system from the results obtained. The developed skiing simulator uses these results in real time. During subjective evaluation tests using the simulator, the subjects operated the edging angle of ski. Using the simulator, the subjects could subjectively evaluate the fitness of an effective side-cut of ski for turn in the same way as in an actual turn of snow surface.

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Analyzing activity of the muscles in human motion is one of the most important things in the development of sports science. In this study, in order to evaluate the activity of the muscles in skiing turns by means of biomechanical analysis, the following experiments were conducted. The first experiment was with regard to the measurement of the state of human motion and the external force acting on the body. The motion of a skier was measured by magnetic position-sensors. The reaction force from the snow surface to the skier was measured by use in 6 axis force sensors embedded in the bottom of ski boots. Then the joint moment and muscular tension could be calculated by using a rigid link model and a musculo-skeletal model respectively. Furthermore, in the calculation of the join moment, the results calculated by static and kinetic analysis were compared and discussed. It was found that the calculated values by these two methods almost agreed. The experimental results showed that characteristics of the physical exercise in skiing turn can be evaluated through the analysis of activity of the muscles. However, the action of antagonists cannot be included in the value of muscular tension calculated through the motion analysis. Therefore, in the next experiment, a change of EMG of the lower limb in the motion simulated to the skiing turn will be measured in a room to estimate the effect of the action of antagonists. Our evaluation method stated in this paper is useful not only for biomechanical analysis of ski sport but also for developing ski goods.

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Since the Japanese-style bow is very complicated in shape and structure, torques in horizontal and sagittal planes about the grip must be applied to hit the target. The purpose of this study was to investigate the relationship between left forearm muscle activities and torques in horizontal and sagittal planes about the grip. Surface EMGs of four muscles (extensor carpi radialis longus, extensor digitorum, extensor carpi ulnaris, flexor carpi ulnaris) and torques were collected for ten male subjects shooting arrows. Crosstalks between EMGs obtained from adjacent recording muscles were evaluated by using cross-correlation function. Absolute values of less than 0.3 of cross-correlation coefficient were considered as a criterion for specific EMG signals. As a result of statistic analysis. Extensor digitorum and extensor carpi ulnaris muscles had positive relationships to the torque in the horizontal plane. On the other hand, extensor carpi ulnaris, flexor carpi ulnaris and flexor carpi ulnaris muscles had positive relationships to the torque in the sagittal plane. It is found that extensor carpi ulnaris is a bifunctional muscle in release technique (TENOUCHI) of Japanese-style bow.

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Potential sports participants are one of the most important targets to be considered in the implementation of strategic marketing plans for promoting sports. The purpose of this study was to make clear a model that analyzes the sports population by analyzing the structure and characteristics of the potential market segment among walking participants, whose population is growing rapidly in Japan. The subjects of this investigation were one thousand people of over twenty years old, who were randomly selected in Tokorozawa-city. This study classified their segments of walking participation into four markets, continuous by active market, uncontinuous by active market, potential market, and non-interest market. This paper analyzed the characteristics of a potential market segment according to attitudes toward health, rate of participation in sports per week, and reasons of participation in sports. The numbers of respondents to the questionnaire were 483. The results are as follows: 1.This study found that over half of the subjects participated in walking. Classified into market groups these walkers showed rates of 39 .5%, 14.6%, 13.7%, and 32.5%, in the categories of continuous by active market, uncontinuous by active market, potential market, and non-interst market, respectively. 2.The differences of attitude toward health among people in the potential market were classified according to rate of participation in sports. As a result, it was found that the segment that did not participate in sports at least once a week tended to have a weak attitude toward health.

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In the 1980s, membership in fitness clubs, consisting mainly of studios and gyms became popular, and became the base of today's growth. Attracting female customers was the big reason the U.S. fitness industry made progress rapidly and greatly. The Japanese and the U.K. markets have been influenced by what happened in the U.S., and female customers have become the spring of early industrial prosperity. The purpose of this research is, by reference research, to clarify the trends of the fitness industry in the world fitness, mainly through reference to the industrial advanced nation the U.S., where the market scale exceeded 1 trillion yen, and also through reference to the fitness industry performance in Japan and U.K.. The following are the major findings. The membership in fitness clubs throughout the world is approximately 57 million. The market size next to that of the U.S. is 300 billion yen in Japan, followed by 240 billion yen in U.K., and 175 billion yen in Brazil. It is said that the European market may reach 1-1.4 trillion yen potentially. The U.S. membership is 30 million, Japanese is 2.9 million and U.K. is 2 .4 million. U.K. membership increased to as much as 26%. Regarding the number of listed companies. U.K. has nine companies, the U.S. has three, and Japan has two. The major companies are carrying out overseas expansion. Private investment companies estimate that this market promises to expand. Life cycles of studio programs have been extended by introduction of a series of new programs. Middle and older aged members are increased in Japan, owing to innovations. Fitness industry associations in Japan, U.S. and U.K. are working together closely for industry development.

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