The purpose of the present study was to clarify the influence of swing parameters by changing the hitting point in space in baseball batting. Twenty-eight skilled baseball players (12 professional and 16 universitylevel) participated. The participants were instructed to hit a ball that was tossed from 5 m away in the direction of the pitching mound. The balls were tossed to various locations with reference to the home plate. The participants were required to hit the balls in a specific direction according to the tossed course, i.e., a ball tossed to the inside of a home plate was stroked toward the same-field direction and one tossed outside of the home plate was stroked toward the opposite-field direction. The motions of the ball and bat during these attempts were recorded using a motion capture system operating at 500 Hz. The 3D coordinates of the ball center (hitting point) and the swing parameters included the speed of the head of the bat (bat-head speed) and the angle of the swing from a horizontal line (swing angle) measured immediately before ball impact and the time from the start of the swing to ball impact (swing time). These parameters were calculated in each trial. Analysis of a total of 644 trials revealed that the bathead speed tended to increase as the hitting point moved inside, forward, and low. Furthermore, the swing angle and swing time tended to increase as the hitting point moved inside, forward, and high. Stepwise multiple regression analysis demonstrated that the bat-head speed and swing angle were independently associated with (in the following order) the distance in the pitcher’s direction, the hitting height, and the inside-outside direction course (R2=.360 and R2=.589, respectively). These results suggest that the timing of swing initiation and bat acceleration during a swing motion are the main factors changing the swing parameters, and that in order to sharp hit a ball, it is important to impact the ball with the hitting point as close to the pitcher as possible.

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　The present study aimed to define the phases of the 110m hurdle race and to clarify the relationship between the race pattern and performance of elite hurdlers. Seventy-six male hurdlers (groups: G1, 12.94–13.38 s, n = 24; G2, 13.40–13.68 s, n = 26; G3, 13.70–14.16 s, n = 26) participating in official competitions were videotaped using high-speed video cameras panning from start to finish (239.76 or 299.70 Hz). The landing step after hurdling was defined as the first step, and the take-off step was defined as the fourth step. The timing of each step and each interval (from touchdown on the landing step to the next landing step) were calculated. Intervals were divided into the acceleration phase (G1: from 1st to 2nd, G2 and G3: 1st), maximum velocity phase (G1: from 3rd to 5th, G2 and G3: from 2nd to 5th) and deceleration phase (G1, G2 and G3: from 6th to 9th). The results obtained were as follows: 1) Faster hurdlers sprinted with a shorter time and a larger mean interval velocity in all phases; 2) G1 had longer acceleration segments and larger acceleration from the acceleration phase to maximum velocity phase than G2 and G3 because of the larger increase in the frequency of the second step; however, deceleration from the maximum velocity phase to the deceleration phase showed no significant difference according to performance; and 3) the pattern of change in the mean interva3l velocity during the race was similar between G2 and G3.
　These results indicate that athletes in G2 need to improve their race pattern to achieve a larger acceleration in the 2nd interval by sprinting with a larger increase in the frequency of the second step. Improvement of the race pattern is less important for G3. Additionally, G2 and G3 need to improve their sprinting velocity to obtain a higher frequency at the fourth step.

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　The purpose of this study was two-fold; to determine the optimum impact condition for maximizing flight distance toward the opposite field and to examine the influence of the bat angles at impact on the batted ball characteristics (speed, rotation, and angle immediately after impact) and the flight characteristics (distance, trajectory, and time). Various impact conditions were defined using 3 factors: the angles of the bat at impact projected to the horizontal and vertical planes, and the vertical inclination angle of the line of impact (the product of the sine of this angle and the radius of the ball determines the under-cut distance). Three-dimensional finite element analysis was used to construct a model of impact between a baseball and a wooden baseball bat and to conduct simulation analysis. The initial flight condition of the batted ball after the impact was determined for each simulated condition, and the flight distance was estimated from the initial flight condition. The results showed that a nearmaximum flight distance of 90-95 m was attained over a wide range of the opposite field when the bat head was not lowered substantially more than the grip-end. However, when the bat head was lowered substantially more than the grip-end, the flight distance attainable with the given impact condition decreased as the vertical bat angle increased, and the range of horizontal bat angle within which a great flight distance was attainable became narrower. The latter results suggest that a batsman needs to acquire a sophisticated technique with a greater precision of ball impact to hit a ball toward a given horizontal angle in the opposite field if the bat swing is characterized as lowering of the bat head to a large extent.

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　The elements of artistic gymnastics have shown a tendency to change over time. Along with such changes in technique, the value of each element will vary. If values that have been historically shared and developed are not recognized, elements and techniques currently in use cannot be understood and the future direction of development cannot be predicted. In order to understand the value associated with gymnastics development, it is necessary to research the historical transition of elements and techniques that has occurred. The evolution of elements and techniques up to around 1970 was described in “Coaching of Artistic Gymnastics” (Kaneko, 1974). Up to the present, however, the historical transition of elements and techniques that has occurred since then has not been thoroughly analyzed.
　In the present study, therefore, by organizing trends in the historical development of elements and techniques related to the pommel horse, we attempted to clarify the factors that have been involved, in order to provide knowledge that might be useful for developing a systematic theory of gymnastics elements.
　Our study yielded the following noteworthy points:
1) The 1970s were a period in which a balance existed between the original elements and elements that complicated existing structures.
2) The 1980s were a period that saw a bias towards the complexity of existing structures, such as those that did not possess pommels or flairs.
3) The 1990s were a period that saw bias towards a combination of elements.
4) From 2000 onwards, developments designed to make existing structures more complex were becoming active.
5) The two-legs system in the pommel horse has seen the development of structural complication triggered by original elements that were present in the 1970s.
　Furthermore, the above-mentioned trends in the development of pommel horse elements have had the following influences:
1) Changes in the shape of the pommel and the adjustment width between the pommels to facilitate support.
2) Changes in technique due to postural simplicity with the intention of achieving maximum amplitude.
3) Changes in the “Code of Points” that emphasize objectivity and the recommendation of high-difficulty value elements.

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　The present study aimed to identify the features of movement involved in a quick change of backward direction (COD) in response to a light stimulus. Thirteen male soccer players performed the Reactive Agility Test (RAT) involving a light stimulus and sprint running. For this analysis, the players were classified into 2 groups according to RAT time: fast and slow. Sprint time, step parameters, and various kinematic variables were compared between the 2 groups. In terms of sprint time, no significant inter-group difference was observed, but in terms of RAT time, the fast group showed significantly greater speed from 0 to 3 m, from 5 to 13 m including the COD, and from 0 to 13 m, than the slow group. Among step parameters before and after the COD, the fast group showed a significant increase in step frequency before the COD, and the time until the COD foot contact and the time until the lowest point of the velocity of the center of gravity were significantly shorter. In the movements before and after the COD, the fast group tilted the body backwards while maintaining a low center of gravity and performed a recovery action of the swing leg by bending the hip joint of the COD foot in the pre COD phase. In the COD phase, the knee joint of the COD foot was considered the flexion position, and the angular displacement of the knee was small, the body tilting inwards and forwards. Furthermore, the body and the shank tilted forwards in after COD phase. Therefore, it was clarified that deceleration occurred and ended early, and that the movement for deceleration was initiated before COD in order to perform it quickly. The findings of this research can be considered basic knowledge for training in order to improve COD performance and to create new indicators for evaluating it.

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　The vast range of gymnastics exercise elements must be clearly distinguished from one another by name for use in judging and training. In recent years, as specific terms including those coined by performers themselves have been used to designate gymnastic skills, it has become very important to examine the criteria for establishing scores and for naming of skills. Current regulations for scoring of gymnastic skills written in Japanese have focused on the requirements for establishment of such skills, with the understanding that “all skills with circle elements start and finish with front support”. However, the problem with this type of regulation is typified by the pommel horse skill known as Russian Circles, or “roshian” in Japanese. The purpose of the present study was to investigate the problems associated with regulation of new pommel horse skills by conducting systematic analysis using phenomenological-morphological methodology to confirm the problems associated with pommel horse Russian Circles.
This study revealed the following 2 points:
　1. Since 1985, the German term “Russenwendeschwung” or “Russenwende” has been employed to score skills that are not agreed upon, and its role as an agreement term has collapsed. “Roshian” is a Japanese translated word allocated to the above skill, but has lost its function for distinguishing such skill.
　2. The requirement for establishing skills, “all skills with circle elements start and finish with front support”, has been shown to lead to inconsistency, creating difficulty with skills and scoring. Moreover, this requirement destroys the concept of skill type, so that tasks unrelated to turning, such as “putting both feet in” and “taking both feet out”, are not be regulated as a requirement for turning skills or turn travel-type elements.

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　The purpose of this study was to consider the direction of research on physical education as “becoming.” A full discussion of this topic poses several problems. The first is that the meaning of “semantic generation” in education is indistinct. The second is that the relationship between the experience of melting into the world (yokai taiken) and the special experience (peak experience/experiencing flow) arising from bodily movement has not been fully discussed. The third problem is that the methods for arguing about the special experience (yokai taiken) as “non-savoir” is obscure. These problems have led to a loss of direction in studies of physical education as “becoming”. The present study was an attempt to overcome these problems in order to clarify a suitable direction of research on this topic.
　The results of this examination were as follows:
　1) “Semantic generation” in education involves making, creating and generating an intellectual sense or meaning. In this context, however, “becoming” yields different phases of meaning. “Becoming” in the educational context is considered to involve reconstruction of a new world view that transcends usefulness, and special experience (yokai taiken) is considered to be of great importance to education as “becoming”.
　2) “Becoming” arises through special experience (yokai taiken), which melts into the special world beyond the self (ecosystem) through a genuine interest in the object (allocentricity). The special experience (yokai taiken) and the special experience that arises from bodily movement are much the same. The experience of bodily movement has a close relationship to the end and the means. However, this special experience (yokai taiken) occurring through bodily movement represents liberation from the useful relationship between the end and the means. This is the beginning of education as “becoming.”
　3) The special experience (yokai taiken) occurring through bodily movement is the beginning of education as “becoming” and the experience has been designated “non-savoir.” The situation of “non-savoir” is an absence of “wit” and “noesis”, and no study can argue the situation as “non-savoir.” Nevertheless, as the experience of “nonsavoir” elicits certain effects, a study can argue the effects of the experience.
　1) Physical education as “becoming” ought to be considered as a reconstruction of a new world view that transcends the usefulness of action.
　2) The special experience (yokai taiken) occurring through bodily movement ought to be considered as an educational experience, separated from the relationship between the end and the means.
　3) The experience of “non-savoir” occurring through bodily movement ought to be discussed in terms of the effects of the experience.

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　The aim of this study was to clarify the relationships between performance in the female triple jump and the run-up speed, phase distances and ratios, in order to propose basic target values corresponding to performance level. The subjects were 100 female triple jumpers (official record: 15.20―11.23 m) who participated in the World Championships (WC) and competitions held in Japan. They were divided into 5 groups based on the effective jumping distance (15G: ≥ 15.00 m, 14G: 14.00―14.99 m, 13G: 13.00―13.99 m, 12G: 12.00―12.99 m, 11G: ≤ 11.99 m). The run-up speed and phase distances in the WC were collected with reference to previous reports of the WC trials, and those of the Japanese competitions trials were measured using a laser distance measurement device (LAVEG) and a high-speed camera. The result of correlation analysis revealed that significant positive correlations were found between performance and the maximal run-up speed (r=0.878) and phase distances (r=0.826―0.907). However, phase ratios were not correlated with performance (r=-0.110―0.082). Comparison of the 5 groups revealed that 15G, which represents world elite level, developed performance by significantly extending the jump distance, although the hop and step distances were not different from those of 14G. In 13G representing Japanese elite level, performance was developed by significantly extending the hop and step distances relative to 12G, and the step distance in 13G was as long as that in 14G. On the other hand, the hop and jump distances in 13G were not as long as those in 14G. These results suggest that the run-up speed and phase distances are important factors for development of performance, although the strategy for acquiring the jumping distance in each phase differs with performance level.

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　The purposes of this study were as follows: 1) to clarify the competition performance structure of the decathlon; 2) to classify performance types based on competition performance structure; and 3) to propose a method for discrimination of performance types. The subjects were 2717 decathletes included in a decathlon data set (Unwin, 2015). The athletes’ total scores were distributed within the range of 6800-9026 points, and were considered to represent a high-level sample. In this study, the competition records of 10 events were used to estimate the competition performance structure and classify the performance types. Total points scores were used to determine the competition levels of each performance type. Parallel analysis and factor analysis (oblique solution) revealed a competition performance structure consisting of 4 factors, which were labeled “running speed”, “explosive arm strength or object projection”, “running endurance”, and “body projection”, respectively, and largely corresponded to those proposed by Linden (1977). Latent profile analysis was applied to the 4 factor scores, and this discriminated 6 performance types as follows:
　1. Track type: T type
　2. Speed and field dominant type: SFD type
　3. Thrower type: Th type
　4. Balance type: B type
　5. Field type: F type
　6. Speed and field type: SF type
　Canonical discriminant analysis of the performance types was conducted using the records of 10 events as independent variables to estimate the discriminant functions, which were saved to an RDS file for statistical analysis using R software. It was possible to discriminate individual decathlete performance types by applying the same discriminant function with the saved RDS file.

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　The purpose of this study was to examine the effects of a combined training program involving isokinetic exercises on male and female students. The participants, 24 male and 28 female college students, were divided into 4 training groups: G180 (180 deg/sec), G60+180 (60 deg/sec+180 deg/sec), G180+300 (180 deg/sec+300 deg/sec), and Gall (60 deg/sec+180 deg/sec+300 deg/sec). The number of repetitions was set to ensure that each group’s total work was approximately the same. All trained 3 days per week for 8 weeks. The maximum torque in each training group increased significantly at a low speed (60 deg/sec) in the low speed combined group and at high speed (300 deg/sec) in the high speed combined group. Additionally, medium speed (180 deg/sec) was increased significantly in all training groups. With regard to the rate of increase in maximum torque per unit body weight, there was no significant difference in the rate of increase in the test load in each group for both males and females. The rate of increase in maximum torque per unit body weight for males did not differ significantly among the 4 groups, but G180+300 and Gall were significantly higher than G180 for females. With regard to the difference between males and females in terms of the increased rate of maximum torque per unit body weight in the training groups, the rate for females in G180+300 and Gall was significantly higher than that for males. These results revealed that males were not effective in combined training involving isokinetic exercises. The training combined with high speed appeared to be effective for females in that the latter had a better effect than for males.

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　The present study aimed to examine the temporal and spatial information used by baseball catchers when making decisions about fielding in pairs. The subjects were 7 collegiate baseball catchers. The experiment was carried out in the defense scenario of a sacrifice bunt with no outs and a runner at first base in the actual field. The participants made decisions about 1) the player (catcher or pitcher) who caught the ball, 2) where to throw the ball (first or second base) when catchers caught the ball, and 3) instructing a teammate (i.e., the pitcher) where to throw the ball (first or second base). The data were subjected to canonical discriminant analysis using a stepwise method according to the type of decision, using the player who caught the ball (catcher or pitcher) and the base at which to throw the ball to (first or second base) as a dependent variable. Ball velocity, ball direction, catching distance, catching time, running time, runner velocity, and runner displacement were used as explanatory variables. The results indicated that 4 explanatory variables – ball velocity, ball direction, catching time, and catching distance – were incorporated in the 3 discriminant functions, and that the discriminant predictive value was 84.1%. From the discriminant functions, it was shown that 1) decisions about the player who caught the ball were based on prediction of the position where the player caught the ball (i.e., catching distance) using information about ball velocity, 2) when catchers made decisions about the base they threw to, they used information about ball velocity and direction, and the time required to catch the ball (i.e., catching time), and 3) when catchers instructed a teammate where to throw the ball, the decisions were based on prediction of the time required to catch the ball (i.e., catching time) using information about ball velocity. These results suggest that catchers make decisions about fielding in pairs using information about ball velocity and direction, the time required to catch the ball themselves (catcher) or by their teammates (pitcher), and the catching position of both players.

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　In the take-off motion of the high jump, huge power exerted by the lower limb is required in a very short time. Consequently, to achieve the take-off motion, improvement of power exertion ability is important, and most high jumpers work to achieve this. However, the components of the kinetics that contribute to high jump performance are unknown.
　This study investigated lower limb joint kinetics during the take-off phase of the high jump and the relationships between kinetic variables and performance. Seven male high jumpers were investigated. Their take-off motions were filmed using an infrared camera (Vicon Motion System, 250 Hz), and the ground reaction force was recorded using a force platform (Kistler, 9287C, 1000Hz). The coefficients of correlation between the vertical velocity of the center of gravity of the whole body (CG) at the moment of take-off and kinetic variables were calculated. The following results were obtained:
　1. The muscles involved in hip extension play a primary role in shock absorption at the moment of touchdown. Furthermore, the muscles involved in hip abduction, knee extension and ankle plantarflexion play a significant role in lifting the body in addition to the above functions.
　2. The concentric power produced by hip abductors during the take-off motion may increase vertical velocity of the CG at the moment of take-off.
　3. As it has been reported that single leg exercises impact the function of hip abductors, such exercises may improve take-off motion in the high jump.
　These results illustrate the characteristics of take-off motion in the high jump, and these may be studied further to plan effective training aimed at improving performance.

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　In when riding in a group during cycling competitions, cyclists may become located side-by-side during positioning, rotation, and overtaking. The primary objective of this study was to analyze aerodynamic variation with differences in the number of riders (1 and 3) while cycling in parallel. It was assumed that the last cyclist would be riding in parallel with the immediate leading cyclist in the group. Wind tunnel experiments were implemented using a static mannequin and athletes as participants. A floor-mounted 6-component force balance was employed for conducting the measurements, and the athlete sat on a bicycle mounted on a bicycle stand.
　Experiments were subsequently conducted on groups comprising 2 riders (2R) and 4 riders (4R). The aerodynamic drag of the last rider (i.e., the mannequin) was measured for a wind speed of 16.67 m/s and for various relative spatial positions with respect to the front end of the immediate leading rider’s front wheel as the origin (longitudinal distance X = -1.38 m–0.07 m, lateral distance Y = 0.25 m–0.90 m; X = -1.38 m was applied solely when Y = 0.90 m for the case of 2R). The results indicated that at Y = 0.75 m–0.90 m, the drag of the last rider for both the 2R and 4R cases was equal to or higher than that for the single state. At Y = 0.50 m, the drag in the 2R case was equal to or higher than that for the single state (maximum value, 108.5% of the single state), whereas the drag in the 4R case was less (87.8–95.1%).
　It was also found that when a parallel cyclist approached a riding group comprising 3 or more cyclists, it was possible to decrease the drag to a value less than for the single state by riding in a position strictly adjacent to the riding group.

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[in Japanese]

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　The purpose of this study was to clarify the actual situation of two-footed takeoff and landing (i.e., twofooted synchronism) during continuous two-footed hopping in young children (aged 4—5 years) and the effect of two-footed synchronism on spatiotemporal body control.
　The participants performed continuous two-footed hops for 10 blocks as quickly as possible. The total movement time required to hop 10 blocks was measured, and the participant’s hopping movement was recorded. The accomplishment rate of two-footed takeoff and landing, the flight and ground contact times, and the displacement of the trochanterion were analyzed for each hopping movement. The main results were as follows.
　1. The rate of accomplishment of two-footed takeoff was higher than that of two-footed landing, and there was a significant correlation between the rates of accomplishment of two-footed takeoff and landing.
　2. The ground contact time was longer than the flight time, and showed temporal variation. There was spatial variation in the anterior movement because the coefficient of variation of horizontal displacement of the trochanterion was greater than that of the vertical displacement.
　3. The higher rate of accomplishment of two-footed landing was related to a shorter ground contact time, a smaller horizontal displacement, and a shorter total movement time.
　In particular, the accomplishment of two-footed landing was found to be the most important factor affecting quick and stable hopping. These results suggest the importance of viewing the developmental characteristics of spatiotemporal body control ability in locomotion, focusing on two-footed synchronism of the continuous twofooted hopping process.

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　The Great Kanto Earthquake of 1923 that struck Tokyo was one of the largest-scale disasters in the history of Japan. Almost half of the city was destroyed by fire. This paper describes how the government constructed new athletic parks in Tokyo under a policy recommended by “Dainippon Taiiku Kyokai”, the Japan Amateur Athletic Association” (JAAA). The findings were as follows.
　1) After the Great Kanto Earthquake, the JAAA held a meeting of the board and submitted a proposal to both the president of the Imperial Capital Reconstruction Department and the Mayor of Tokyo. It requested the government to construct new athletic parks in affected areas of Tokyo in order to cultivate the physical strength and mental health of citizens.
　2) The government officially received the proposal and constructed 3 new parks (Kinshi Park in 1928, Hamacho Park in 1929, Sumida Park in 1931). Various sports facilities such as athletic fields, tennis courts, and swimming pools were set up in each park. Notably, pools had a night lighting system installed for office workers and arranged specific hours for women only.
　3) In particular, various events for general citizens were held at Sumida Park. These included a comforting sports day for city officers’ families, public radio calisthenics, and a baseball league made up of Kabuki actors. In a commemorative bulletin issued in Tokyo, the park was referred to as “Downtown Olympia”. In the 1920s, the early period of sports history in Japan, athletic parks were arranged at the request of the JAAA in the post-disaster phase. These 3 parks, still in existence, supported the development of sports in prewar Japan.

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　In postwar Japan, the United States (US) could be viewed as Japan’s “significant other.” The US had a considerable cultural impact on Japan and was responsible for alterations in postwar Japanese identity. Of particular importance was the influence of the US on the popular view of body form. The postwar restructuring of Japan’s national identity included the adoption of new views of the body as a result of US influence. This study investigated the culture of male beauty/body (bodybuilding) that emerged in Japan during the postwar period of occupation, and revealed how “male beauty” consciousness was generated in relation to nationalism by focusing on (1) the social context in which “male beauty/body culture” emerged and (2) the changes in conceptions of masculinity and body consciousness. This analysis yielded the following results:
　(1) Bodybuilding emerged in the social context of the occupation/reconstruction period and from a masculine crisis of male feminization in Japan. It was developed by the Japan Bodybuilding Association (JBA) as part of a movement to create “new Japanese men”.
　(2) However, bodybuilding was criticized as being feminine, linked to homosexuality, and leading to a useless “Hercules-type” body.
　(3) In response to this criticism, the JBA shifted its aim from the acquisition of a burly, Herculean build to one of a healthy and functional (“Hermes-type”) body that represented harmony between the body and the spirit. The aim of this shift was to gain legitimacy for bodybuilding as a masculine act.
　In addition to these aims in trying to help create “new Japanese men”, the JBA also intended to legitimize male bodybuilding culture within a national context, seeking to popularize and expand its activity by criticizing the American “Hercules-type” body while promoting the “Hermes-type” body preferred in Japan. In this way, discourse concerning the legitimacy of male beauty/body (bodybuilding) culture developed in conjunction with nationalism, and created an important forum for consideration of the ideal Japanese male body form.

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　The present study compared the kinematics of lower limb and trunk motion in lateral cutting maneuvers (180° turn) during side steps under preplanned (PRE) and unpredictable (UN) conditions in defensive basketball players. The participants were 14 players from a college female basketball team who were instructed to view an arrow directed either to the right or the left on a monitor in front of them while moving with side steps toward the right. When a right-directed arrow was provided, they side-stepped 3 m by to the right, whereas a leftdirected arrow prompted them to move 3 m to the right, perform lateral cutting to the left, and to move back to the starting spot with a side step. Trials were performed under 2 conditions: 1) PRE condition: Participants were informed about the direction of the arrow signal beforehand. 2) UN condition: Participants responded to a randomly presented direction of the arrow signal. Kinematic parameters and ground reaction force (GRF) data were collected using an optical three-dimensional motion analysis system at 300 Hz and a force plate at 1500 Hz. The data only in the lateral cutting trials were analyzed from the instant of foot strike on the force plate to the instant of toe-off during lateral cutting. The results showed that the 3-m side step shuttle time and foot contact time during lateral cutting in UN were longer than those in PRE. The horizontal component of the maximal GRF and the impulse during lateral cutting in UN were larger than those in PRE. The center of gravity (CG) lateral velocity toward the right at the cutting step foot strike was higher in UN than in PRE. In UN, the right lower limb and trunk were inclined less to the left than in PRE. The present results show that, in UN, the participants were unable to reduce their lateral velocity before the cutting step and that their right lower limb and trunk at the cutting step (middle phase) were inclined relatively to the right, thus increasing the degree of movement of their CG to the right. Therefore, the participants needed some time to move their CG back to the left, which prolonged the contact time and thus the time taken for the 3-m side step shuttle movement in UN.

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　The present study involved a cross-sectional investigation of the arm swing direction during sprint running in order to clarify age- and gender-dependent characteristics and specificities. A total of 457 subjects of both sexes ranging from elementary school children to adult sprinters were visually assessed during sprint running and classified as “longitudinal direction” (Type 1), “mixed” (Type 2) or “lateral direction” (Type 3) based on the direction of their arm swing. The results were as follows. 1) The side-to-side range of the Type 3 swing decreased with advancing age for males, whereas this type accounted for the highest proportion among all age groups for females, except for lower elementary school students. 2) Among high-performance sprinters, the majority of males were Type 1, whereas females were Type 3. 3) Except for boys in the upper grade at elementary school, one-way ANOVA of the sprint run time among swing types for the various cohorts showed no significant differences. These findings suggest that there is a gender-dependent difference in arm swing direction during sprint running. Furthermore, unlike previous reports that have recommended longitudinal swing (back and forth) for high-performance achievement, the present results suggest that female sprinters can accomplish this even with a lateral swing.

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　The purpose of this study was to clarify guidelines for cooperation within an entity known as a “team” that transcend the individual, based on the theory that universal validity criteria and norms that are inherent in them play an important role in team victory. For this purpose, procedures were taken to outline team values and then formulate guidelines that are universally valid by extracting value criteria and normative principles from the analysis. The study results were as follows. 1) It was suggested that criteria allowing distinction between acceptable and nonacceptable actions performed by the team are essential for collaboration among individual athletes, and that conversely, a convergence of various values occurs among athletes. 2) The success or failure of collaborative acts should be based on 2 criteria: “whether or not team performance can be improved,” and “whether or not individual athletes can be satisfied.” In addition, it was clarified that teams and individuals acted in a binary manner, allowing the team to inspire individual athletes, while at the same time individual athletes inspired the team. 3) Finally, it was concluded that team victory is supported and ordered by 2 criteria with a normative principle that “personal assets accumulated through standard value judgments of ‘whether or not personal talents are utilized’ do not reside with the individual as a right of nonaggression, but must be used for the team as a whole in accordance with its needs.” It is anticipated that the present findings will not only help to solve practical problems in team sports, but will also contribute to the debate over athletic capability, which plays an important role in establishing team performance.

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　The javelic ball throw using a JaveBall is a track and field event designed for elementary schoolchildren and is regarded as an introduction to the javelic throw, an event for junior high school students, which in turn is an introduction to the javelin throw, an event for high school students and beyond. This study examined the effect of release parameters on flight distance in the javelic ball throw. Flight distances and release parameter values of 146 throws by 17 participants were measured. Initial velocity was the parameter with the strongest influence on flight distance. Release angle, angle of attack, and horizontal angle of attack had some influence, but flight distance did not differ markedly even when the values of these parameters were very low or very high. The ratio of the actual flight distance to the theoretical flight distance decreased with increasing initial velocity, indicating that achieving a greater actual distance becomes more difficult as the release velocity increases. Although the rotational speed of the JaveBall around its longitudinal axis was a factor that reduced the actual flight distance relative to the theoretical flight distance regardless of its magnitude, it was considered that the decrease in the actual flight distance relative to the theoretical flight distance will decrease when an extremely small rotational speed is applied without reducing the initial velocity. Although the javelic ball throw is intended as an introduction to the javelic throw, which in turn leads to the javelin throw, this study showed that the characteristics of the JaveBall are not necessarily similar to those of a javelin, for which the rotational speed increases relative to the increase in initial velocity. Athletes and their coaches should be aware of this if they expect to transition from the javelic ball throw to the javelin throw in the future.

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　In football it is necessary to score more goals than one’s opponents in order to win the game. One strategy for gaining goals and scoring opportunities is attacking through the gap between an opposing defender (DF) and a midfielder (MF) (the DF-MF gap). However, research on this form of attack has revealed that it is merely more likely to lead to scoring and scoring opportunities than other forms of attack. In the present study, therefore, through a comparison between the Japanese J League (JL) and the German Bundesliga (BL), we examined the features of DF-MF attack play in the JL and BL and differences between them, in order to clarify the challenges in the JL for creating scoring opportunities. We determined the number of passes into the DF-MF gap, the number of passes from players receiving the ball in the DF-MF gap, and the relationship between receiving the ball in the DF-MF gap and the opposing DF. The sample used for analysis was a total of 40 games: 20 in the JL (2015 season) and 20 in the BL (2015/2016 season). For statistical analysis, independent t test and chi-squared test were conducted. In comparison to the BL, the rate of penetration into the DF-MF gap was lower in the JL. In addition, it became clear that in the JL there was a lower proportion of scoring opportunities such as penetration into the PA and shots when penetrating into the DF-MF gap than was the case in the BL. This was considered to be due to the fact that in the JL, the number of balls received in the DF-MF gap in the direction of goal was lower than that in the BL. Furthermore, in the JL, when the ball was received in the DF-MF gap, the proportion of moves defended from the opponent goal side was higher than in the BL, suggesting a problem in how the ball is received. These findings suggest that in the JL it is necessary to increase the opportunity for scoring by making it easier for the ball to advance in a goalward direction by receiving the ball when separated from the opponent DF.

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　An integrated coaching system was adopted by the Japan Handball Association (JHA) in 2000, but in terms of international competition its results have been less than satisfactory. According to a survey by the Ministry of Education, Culture, Sports, Science and Technology, the effectiveness of the integrated coaching system is directly related to achievements at the Olympic Games. Therefore, in order to improve the competitiveness of Japanese Handball at international level, it is pivotal to seek out problems within the system so that further improvements can be made.
　This study was aimed at identifying ways to improve the effectiveness of the integrated coaching system for Japanese handball by comparing the patterns of promoting factors as well as inhibiting factors in the process of implementing the said system for representative teams in the JHA, the Japan Football Association (JFA), and the Japan Volleyball Association (JVA). To this end, interviews were conducted with 6 former chairmen or deputy chairmen of committees related to the integrated coaching system in the JFA, JVA, and JHA. A qualitative analysis of these interviews was performed and the following findings were obtained.
　1. There appear to be 3 main issues with the JHA integrated coaching system: 1) The athlete development program has not been revised; 2) The athlete development program has not been properly implemented throughout the nation; 3) The program lacks visibility.
　2. Three countermeasures have been suggested to tackle the above issues: 1) Reorganize the programs based on objective data; 2) Allow leaders to communicate new development principles to teams across the country; 3) Create a new excavation/nurturing location where many people gather.

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　Here, in comparison with community-dwelling middle-aged and older men, we investigated the skeletal muscle mass and bone mineral density of a Japanese alpinist (Mr. A) who, at the age of 80 years, is to date the oldest person to have climbed to the summit of Mount Everest (8,848 m). Using dual X-ray absorptiometry, we determined the appendicular skeletal muscle mass index (SMI), total bone mineral density (tBMD), whole body fat-free mass index (FFMI) and fat mass index (FMI) of Mr. A (84.6 yr) and 209 community-dwelling middle-aged and older men (50-79 yr, mean age: 68.1 yr). The SMI, tBMD, FFMI and FMI were 8.79 kg/m2, 1.075 g/cm2, 22.3 kg/m2 and 9.8 kg/m2, respectively, in Mr. A and 7.46 ± 0.81 kg/m2, 1.020 ± 0.100 g/cm2, 18.1 ± 1.9 kg/m2 and 5.5 ± 1.7 kg/m2, respectively, in the community-dwelling middle-aged and older men. The values in Mr. A were higher than those in the community-dwelling middle-aged and older men, with z-scores for the SMI and tBMD of 1.63 and 0.55, respectively. Mr. A maintained a high skeletal muscle mass and bone mineral density even at the age of 84 years, which may have been attributable in part to his long-term training for mountain climbing.

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　The present case study was conducted to examine the learning outcomes of junior high school students given sprint running instruction focusing on kinesthesis. We analyzed changes in the 50-m running time, intermediate running speed, maximum running speed, rate of decrease in running speed, running movement score, and kinesthesis for 5 hours of classes given to junior high school second graders.
　The study clarified the following four points.
　1) The students showed significant improvements in their 50-m running time, intermediate running speed and maximum running speed, and significant decreases in the rate of decrease in their running speed throughout the 5-hour unit, which had been designed to configure learning activity by focusing on embodied knowledge of sprinting. With regard to running motion, all items excluding “arm swing direction” were significantly improved. In addition, it became clear that the students had pursued learning while grasping aspects of kinesthesis such as “switching legs”, “pushing the ground”, “stepping on the ground”, and “bouncing from the ground”.
　2) Students in the upper group were conscious of aspects such as “switching legs”, “pushing the ground”, “bouncing from the ground”, and “maintaining speed”. In addition, learning involved capturing not only strength and lightness, but also the rhythm of movement as kinesthesis.
　3) Students in the middle group were conscious of aspects such as “stepping on the ground”, “switching legs”, “pushing the ground”, and “bouncing from the ground”. In addition, in terms of kinesthesis, there was a tendency to express heavy movement and force in addition to lightness of movement. It was thought that the problem lay in being unable to capture well the rebound from the ground.
　4) Students in the lower group were conscious of aspects such as “stepping on the ground”, “switching legs”, and “bouncing from the ground”. In addition, there was no evidence of expression such as capturing the push or repulsion of the ground in terms of kinesthesis, and there was also a tendency for less expression of quickness and lightness of the leg change. It was considered that the main problems lay in accumulation of sufficient experience to improve movement of the lower limbs and to express various aspects of kinesthesis.

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　We examined the process of development of the first professional female volleyball club in Japan, Victorina Himeji, in relation to its stakeholders. For the purposes of this study, a professional sports club was defined as an organization composed of professional athletes who receive compensations through engagement in sports. We collected qualitative data from websites, papers, books, and archive material. In addition, we conducted a semi-structured interview with Mr. Akira Hashimoto, chief executive of Himeji Victorina. This revealed the involvement of 13 primary stakeholders and 11 secondary stakeholders in Victorina Himeji’s development from its conceptual stage up to the present. Analysis of Victorina Himeji’s organizational development over time revealed 3 phases. Phase 1 was the period from the launch of the club-founding preparatory committee until the establishment of the joint-stock company: Himeji Victorina. During this period, Mr. Masayoshi Manabe, who has been the head Japan women’s volleyball coach until 2016, and interested locals joined together with the idea of creating a professional volleyball team in Himeji city, a period during which Mr. Hashimoto later joined and strengthened the management. Phase 2 was the period following the establishment of Himeji Victorina until its official admission to the V. League. This was the period during which the organization conducted tryouts, scouted and collected players with prospects of strengthening the team, and strengthened the main office staff at the club’s headquarters. In addition, Phase 2 saw the beginning of sponsor recruitment, in addition to strengthening of the top team, along with activities to popularize volleyball and train players through the establishment of the general incorporated association: Victorina Elite Academy. Finally, Phase 3 was the period following the official admission to the V. League until the present. Overall, this study clarified the relationships with stakeholders and engagements as a club, which were both crucial elements in the process of founding this professional sports club and ensuring its growth as an organization.

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　The purpose of this study was to clarify the kinematics of the jump floater serve in volleyball to provide basic data for research. The jump floater serve motions of 9 female volleyball players (body height: 174.4±6.2 cm, body weight: 67.7±6.1 kg, age: 23.6±4.6 yr, career: 14.4±5.1 yr) were recorded using a motion capture system with 10 cameras (500 Hz). The three-dimensional coordinates of retro-reflective markers on the volleyball were also collected using a motion capture system. The primary variables examined were the hand velocity of the swing arm at impact, the velocity and angular velocity of the volleyball after impact, the joint angles of the swing arm and torso, and the segment angle of the lower torso during the jump floater serve. The main results were as follows.
　1. The speed of the volleyball was about 14 m/s, and the spin of the volleyball was about 1 rps.
　2. No significant correlation was found between the number of volleyball rotations around each axis and the impact parameters of the swing hand.
　3. The maximal right rotation angle of the torso joint in the jump floater serve was smaller than that of the spike motion.
　4. The abduction angle of the shoulder joint at ball impact in the jump floater serve was similar to that of a spike motion.
　5. From the end of take back to the middle of the serve motion, the standard deviation in the abduction angle of the shoulder joint was notably large.
　6. The maximal external rotation of the shoulder joint was smaller in comparison with a baseball pitch or a tennis serve.
　7. The extension angle of the elbow joint at impact was smaller in comparison with the volleyball spike motion.

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　The purpose of this study was to investigate the actual practice, outcomes and challenges of the Olympic and Paralympic Education Programme in schools through an analysis of the Nationwide Development Project of Olympic and Paralympic Movement 2016-2017. The Japan Sports Agency have been running the Nationwide Development Project of the Olympic and Paralympic Movement since 2016 in association with 12 government bodies, and a further 22 joined in 2017. These government bodies were supervised by 3 universities, who designated specific schools for Olympic and Paralympic Education. The supervising universities held a startup seminar at the beginning of the school year and a workshop in which schools shared their own practices in the form of reports at the end of the year. This study examined the actual practice, outcomes and challenges related to this project through an analysis of these reports. The subjects were 4 prefectures that joined this project in both years: 111 schools in 2016 and 140 schools in 2017.
　The result showed that the most popular activities were lectures and sport experiences with Olympians and Paralympians, and that investigative learning about the Olympic and Paralympic Games and the “I’mPOSSIBLE” programme (IPC) has increased in 2017. Exchange programmes were also conducted with special needs schools, welfare facilities and sport festivals. These activities were intended to stimulate interest and concern about Olympic and Paralympic Games and Sports. The outcome was that students developed life skills, encouraging them to face challenges, make an effort, and to adopt a never-give-up attitude, kindness and sympathy for others through the education programmes. On the other hand, some challenges were also revealed, such as difficulties in inviting the Olympian or Paralympian lecturers and event management, suggesting that the education programmes should be conducted in a more systematic manner from an early stage. The results of this study indicated the importance of making Olympic and Paralympic Education part of the school curriculum and demonstrating the need to continue Olympic and Paralympic Education after Tokyo 2020.

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　The purpose of this study was to investigate the racing characteristics of elite roller speed skaters in a 300-m time trial race (300m TT). The subjects were 21 skaters who participated in the World Roller Speed Skating Championships in 2016. These included 9 skaters who qualified for the finals and 12 who ranked between the 25th and 45th places. Roller speed skaters glide while keeping their feet grounded for a short time in a curve: a movement known as “carrying”. Nine finalists who performed carrying in C2 and C3 were classified as the top group (age 24.2 ± 2.4 years; height 1.8 ± 0.1 m; weight 73.2 ± 7.1 kg). Nine of 12 skaters who performed carrying in C2 and C3 were classified as the subgroup (age 24.0 ± 3.4 years; height 1.8 ± 0.1 m; weight 74.6 ± 7.1 kg), and 3 skaters were classified as the non-carrying group (age 25.0 ± 5.1 years; height 1.8 ± 0.0 m; weight 73.7 ± 2.4 kg). In this study, 300mTT was classified as 4 straight sections – Start, S1, S2, and Finish – and 3 curve sections – C1, C2, and C3. The investigated parameters included the 300mTT goal time (T300), the skating speed in each section, and the time during which carrying was performed (Tcar). In the subgroup and non-carrying group, the skating speeds in S1 were similar, but the skating speed of the non-carrying group in C2 was lower than that of the subgroup. The top group glided at a higher skating speed in every section expect C3. There was no significant difference in Tcar, and there was no significant correlation between T300 and Tcar in C2 and C3. There was a significant positive correlation between T300 and Tcar in C2. In the top group, there was a significant negative correlation between T300 and skating speed at C2. These results suggest that carrying in C2 is important for gliding at a higher skating speed in 300mTT, and that Tcar in C2 and C3 for elite roller skaters does not influence T300. Elite roller skaters had superior acceleration capacity in the Start, and obtained a higher skating speed until S1, after which they maintained a higher skating speed in C2. Furthermore, elite roller skaters were able to achieve a higher skating speed in spite of fatigue in their support legs.

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[in Japanese]

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[in Japanese]

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