The present study aimed to use a Balance Master Platform System to determine the characteristics of the balance ability of a group of male university student athletes who were training in either kendo or judo. Out of 20 students (mean age 22±1) who volunteered to join this study, 10 were kendoka and 10 were judoka. All of them had practiced regularly in their respective sport for about 15 years. In the study, the participants’ static balance was measured by their Sway Velocity (SV), and their dynamic balance, by their Limits of Stability (LOS). Sway Velocity was easured while each man was standing on each of two surface conditions (firm pad or foam pad) of the Balance Master Platform System with his eyes open or closed. The Composite Sway Velocity (SVcomp) scores were calculated based on the sway velocity conditions as an index of Sway Velocity. Components of the Limits of Stability (endpoint excursion [EPE], maximum excursion [MXE], reaction time [RT], movement velocity [MVL], and directional control [DCL]) were evaluated in eight different directions by a computerized balance assessment device, and the composite value of each component (EPEcomp, MXEcomp, RTcomp, MVLcomp, DCLcomp) was used in the analysis. No significant differences were obtained in height, weight, or body mass index between the groups, indicating that the athletes in both groups were similar in physique. No significant differences were obtained in the Sway Velocity parameters between the groups. Among the components of the Limits of Stability, the kendo group had significantly higher scores on RTcomp and MVLcomp, compared to the judo group. These results suggest that these student athletes had improved their balance ability remarkably since entering the university. The discussion contends that further study is needed.

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The present study evaluated the physiological responses of Japan’s top race walker before and after a 100-km race walk around Saroma Lake. The race was conducted in June, 2006. He completed the 100-km walk mingled among many other participants. His time was 9 hours 9 minutes. His weight loss was only 0.1 kg, and his maximal pulmonary ventilation (VE) and maximal oxygen intake (VO2max) were reduced by 54.0 L per min-1(34%) and 0.481 L per min-1 (11.4%) respectively. The reduction of VE was caused by his large reduction in breathing rate (f) of 7 breaths per min-1 (9.2%) and one-time ventilation rate (VT) of 0.57 L per min-1 (26.9%). His ventilator equivalent (Vs/VO2) dropped by 24.9%. At the time when his walking speed was submaximal, in the range of 120～240 m per min-1, his VE after the race dropped by 19.4～29.5%. That decrease was due to the drop of 12.0～35.4% in f and in VT of -10.1～8.8%. His maximal heart rate (HRmax), blood lactate (LT), and rating of perceived exertion (RPE) did not change significantly. A hypoventilation syndrome was observed 3 days after the race These results suggest that for improvement of race walking performance, training of the respiratory muscles may be effective for lessening and recovering from fatigue of the respiratory muscles.

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The present study investigated relationships between 100-m race time, the runners’ height, and wind speed, and split times and segment times, and then estimated equations for calculating the average split times and segment times for the 100-m race time, the runners’ height, and the wind peed. For this analysis, videos of 100-m sprints by 112 Japanese male sprinters (100-m race time: 10.05-11.06 s, height: 1.64-1.88 m, wind speed: －2.2 - +2.0 m/s) were shot with 3 digital video cameras (299.7 fps) during 1 entire race. Split times at the 30-m, 60-m, and 90-m marks, and egment times from the 30-m to 60-m, 60-m to 90-m, and 90-m to 100-m marks were measured using those video images. Multiple regression equations were prepared for all split times and segment times, using multiple regression analyses with stepwise procedure for each time segment as dependent variables, and the 100-m race time, runners’ height, and wind speed as independent variables. The results were estimated equations for calculating the average split times and segment times by 100-m race time, runners’ height, and wind speed in the men’s 100-m sprint. By using multiple regression equations, the race content feature of each sprinter can be presented specifically and accurately. In addition, using the equations, each sprinter can be coached in training that simulates the necessary race content of the target 100-m race time in relation to the runner’s height.

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The present study describes the effective use of game analysis data by the Chiba Lotte Marines, who won the Nippon Professional Baseball Japan Series in 2005, and examines how the game analysis data were used. The article presents the visual materials that were actually used, e.g., pictures and videos showing features of the opponent teams’ batters, and specific instructions, with both diagrams and written text. To illustrate how the game analysis data were used, the article also includes the results of the Marines’ pitchers and the batting results of the opponent’s batters in the first game of the 2005 Japan Series. Taking into account those data and the experience of the first author, who played for the Marines in 2005, good results were brought about by a favorable combination of game analysis and tactics based on the game analysis data. All players should make every effort to use those tactics. Finally, the discussion, based on the first author’s experience, explains how to use game analysis data effectively, and suggests how to eliminate the gap between objective data and players’ subjective impressions, and how to improve the skills of the support staff who key in the data and analyze them.

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The purpose of the present study was to investigate the relevance of a tackle and the next play in sevens rugby by analyzing aspects of tackles and the plays after tackles， and comparing the results to a comparable analysis of 15-a-side rugby． The analysis was done on 20 games from the HSBC Sevens World Series between teams worldranked #10 in 2014 as a sample of sevens rugby, and, for comparison, 10 games in 2014 between teams ranked #10 in 15-a-side rugby ．Analyses were done of the following: number of tackles ， height of tackles, direction ， number of players ， handstands by ball carriers，results of tackles, and results of the next play after a tackle．A descriptive game-performance analysis was used． The main results were as follows: 1） There were fewer tackles in sevens rugby than in 15-a-side rugby． 2） Tackles were done alone, from the rear，more often in sevens rugby than in 15-aside rugby. 3） In sevens rugby，players had more contact, often standing, handling, and passing to teammates even after receiving a tackle. 4） In sevens rugby，once a tackle had been made, it was more likely to be followed with a try and turnover．

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The present study examined features of higher- and lower-ranking windsurfers’ styles of movement during a simulated windsurfing competition. Participants were 7 higherranking and 7 lower-ranking college windsurfers. The results suggested that the higher-ranking windsurfers showed higher VMC (Velocity Made good to Course, i.e., speed in the direction of the mark) and shorter sailing distances due to their higher sailing speed and smaller sailing angle. The higher-ranking windsurfers achieved a higher sailing speed, which resulted in a shorter sailing distance. In the downwind condition, the higher-ranking windsurfers had higher VMC because of their higher sailing speed, even when they had same sailing angle as the lower-ranking windsurfers. The higher-ranking windsurfers’ style of movement at the start included keeping a shorter distance between the boat and the start line, having space for acceleration, reaching a higher sailing speed 0-5 seconds after starting, and maintaining a higher sailing speed and VMC and a smaller sailing angle throughout the starting phase. On the other hand, the lower-ranking windsurfers appeared to take unfavorable sailing positions compared to other boats, such as the preceding boats and windward boats. The above results from simulated competitions reveal characteristics of the movement style of higher-ranking and lower-ranking windsurfers, and suggest how race standings might be enhanced.

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The present study reports the training of a university cyclist who, after participating in track and field jumping events for several years, changed to short-distance bicycle racing just before his senior year at university, and who improved his record in 1-km time trials from 1 minute 38.4 seconds to 1 minute 6.221 seconds in one and a half years, and eventually won a prize in an all-Japan university competition. The present report describes points of technical and tactical training after he started short-distance bicycle events. Active supplemental exercises for the stretching motion of the hip joint are thought to be useful for cyclists for achieving competitive power quickly, and for acquiring a pedaling technique that uses their hip, a starting technique in which they feel the extension of their hip joint, and pacing in 1-km time trials.

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It is considered to be very important to know both the speed and the spin of the ball of top players in tennis. Almost no research has been done on both speed and spin except for Muramatsu (2015, in Japanese), who reported about the service of top world-class players. However, we found no published reports of research on the forehand stroke. The present study focused on both the speed and the spin of the ball of 16 forehand strokes by the world number one male tennis player during competition, and examined their relationship. The ball speed data were obtained from the Hawk-Eye system, which archives ball-speed data from competitions. Ball spin was measured from shots taken with a high-speed camera shooting at 2000 fpm. The regression equation for calculating spin from ball speed was spin (rpm) = -33.2 x speed (km/h) + 7878. The average speed of the 16 forehand strokes was 132 km/h, and the average spin was 3486 rpm. These data may be useful indices for players aiming at improving their competitive power and for their coaches.

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Kendo requires striking with a combination of spirit, sword, and body. Particularly, in the body, the lower limbs are the source of motion, so it is important that the footwork starts with correct positioning of the feet, moving ahead by sliding the feet, and returning to the correct position. Practicing footwork is therefore indispensable for improving technique in kendo. The present study focused on a method for correcting “bouncing foot”, which is considered to be a bad habit in kendo. The participant was a kendo practitioner who had a problem of ouncing foot. It was suggested that he try a training method using a slipper. To analyze the effectiveness of this training technique, comparisons were made of video and stop-motion photographic playback of the kendoka with and without bouncing foot, and using and not using a slipper.

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Control is one of the crucial factors in the success of baseball pitchers. At coaching sites, visual action is often coached in addition to pitching motions. However, compared to a general consensus on coaching pitching motions, there is no agreement about how to coach visual action. In this context, the present study aimed to provide useful information about coaching visual action for the purpose of improving pitching control, by examining influences on the accuracy of pitching control of timing on the acquisition of target information during the pitching motion. The participants, 6 university baseball pitchers, threw the ball toward a target 18.44 meters from the mound. The throwing motion was divided into three phases: windup, cocking, and acceleration. The timing of their acquisition of visual information was changed with shielding glasses. The results suggested that visual shielding from the beginning of the pitching motion until the pitcher’s throwing arm came to the top of his motion (the elbow of his throwing arm was at shoulder height), that is, the windup and cocking phases, hindered pitching accuracy. No influence was found of visual shielding from the top of the motion to the release point (acceleration phase). Moreover, the pitcher with the best control obtained the target information in the first half of the pitching motion, whereas the one with the worst control obtained it throughout the pitching motion. This suggests that coaches’ common advice to watch the catcher’s mitt until the ball has been released may not necessarily be helpful advice.

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Safe and effective teaching of judo requires student judoka to acquire correct ukemi techniques. The passive front roll, or front-rolling ukemi, is particularly difficult to teach, and it can be troublesome to students, too. Thus, it is a difficult technique for both teachers and students. In order to deal with this problem, Hatsutenkun was developed. Hatsutenkun is a specialized jacket, worn instead of the standard judo uniform jacket that assists in the teaching of front-rolling ukemi. Hatsutenkun was designed as a teaching aid for non-professional judo teachers, so that they could conduct effective and safe lessons on the front-rolling ukemi. Previous studies of the effectiveness of Hatsutenkun examined it in terms of subjective evaluations by teachers; objective evidence scarcely existed. The present study, therefore, used pressure patterns and analysis of the students’ behavior to examine the immediate effectiveness of teaching the front-rolling ukemi when the students wore Hatsutenkun. The results with the measure of pressure distribution patterns suggested that teaching by using Hatsutenkun enabled the students to acquire a smooth front-rolling motion. Furthermore, the students’ subjective comments revealed that, in their opinion, the immediate effect on their ukemi was greater than they had achieved when wearing the traditional judo uniform.

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It has been said that, in modern tennis, it is necessary to acquire skill in the groundstroke (Schonborn, 2007). Women players tend not try net play as much as men do (Takahashi et al., 2010). The present study reports observations of a university woman tennis player who had been using mainly groundstrokes from the baseline and who improved her competitive power by expanding from groundstrokes to net play. The participant was a woman tennis player who belonged to the university tennis club. Before entering the university, she used a typical woman’s style of play, based mainly on playing at the baseline. After her second year at the university, she trained constantly on offensive play, including net play. As a result, in her third year, she used net play more frequently and her results at national and local student competitions improved. On the other hand, in her fourth year, she started to feel pressure to play at the net, and her frequency of net play during competitions declined. The experience of this player suggests that women tennis players may be able to improve their competitive power if they expand their use of net play.

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Baseball batters swing the bat based on the information about not only ball trajectory but also the pitcher’s motion. The present study investigated the influence of the length of time to raise and lower the lead foot in the pitching motion on the timing and control of the batter. Participants were 10 college baseball batters. In a batting simulation task, participants attempted to predict the arrival time of the ball at the plate from a video of baseball pitch that occluded 200 ms after the ball was released. The batters were required to swing as if to hit the ball when it arrived at the plate. The videos showed five different types of pitching motions that differed in the speed of raising and lowering the lead foot: normal speed (up = 1000 ms, down = 800 ms), raising quickly (500 ms) or slowly (1500 ms), and lowering quickly (400 ms) or slowly (1200 ms). These videos were presented in a set that contained only one raising and lowering combination (single presentation condition) or in a set of randomly ordered combinations (random presentation condition). The results showed that timing errors and variability of step motion during batting in the random condition were larger than those in the single presentation condition. These results indicate that a baseball pitcher could influence the prediction of ball arrival by using variable durations in lead foot motion.

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The present article proposes a training method using inline skates for improving total jumping distance in the standing five-step jump, and evaluated immediate effects of that method. The participant was a male university jumper; his total jumping distance and the distance and speed of each jump were analyzed with continuous photography. It was found that, after 10 minutes’ training, the athlete’s total jumping distance improved by 0.63 meter, from 14.10 meters to 14.73 meters. This exceeded his past best record, and confirmed immediate effects of the present training ethod. After the training, his jumping speed increased for every step, and, at the 5th step, the total distance jumped greatly increased. At each step of his jumps, the motion of his landing foot and travelling foot changed. In particular, the motion of his landing foot was remarkably improved. This training method suggests an effective way of improving total jumping distance by increasing the jumping distance of each step, and, at the same time, accelerating the jumping speed; it also suggests a countermeasure against problems such as the decrease in speed when jumping istance increases, and the decrease in jumping distance when jumping speed increases.

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The present study reviewed and analyzed the process of team-building with the Kyushu university women’s volleyball team that was selected to participate in the 2009 Volleyball Competition of Men’s and Women’s Teams from Five Universities in Western Japan. The following results were obtained: 1) The victory of the Kyushu team resulted from its successful growth into a winning team in which team members followed the coaches’ advice and built up firm teamwork. 2) For team-building to be successful in a short period of time, quick judgment and decision-making are required. The presence of staff who support the coaches is also important. 3) Coaches must guide every member of the team to shift from individual goals to team goals. 4) Another way to build a team in a short period of time is to have the coaches not force the team members to agree with the coaches’ ideas, but rather to let the team members communicate with each other and actively participate with the coaches in the team-building process. That is how to cooperate to create the team’s style. 5) Coaches should select short and simple words when speaking to team members

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The present study investigated influences of leg muscle power and leg muscle endurance on athletes’ 5000-meter run performance. The participants in the study were 16 male long distance runners from S University’s ekiden team (average age: 19.6 years, best time in the 5000-meter run: average 15 min 27 sec, range, 14 min 40 sec to 16 min 44 sec). The relation of leg extension power (legP), maximum squat jump height (HSJmax), and leg muscle endurance (HDI) to their 5000-best (each runner’s best time in a 5000-m run in the past year) was analyzed. The results were as follows: 1) The runners’ leg muscle power (legP and HSJmax) was weaker than that of typical students of the same age. 2) No significant relationship was observed between their 5000-best and their legP, or between their 5000-best and their HSJmax. 3) A significant relationship (r=0.60, p<0.05) was observed between their 5000-best and their HDI. The participants were divided into 2 groups, based on the runners’ 5000-best time. Group A’s times were shorter than 15 min 20 sec, whereas the 5000-best times of the runners in Group B were longer than that. When the average HDI of Group A and group B was compared, the HDI value of Group A (13.6±4.14%) was found to be significantly smaller than that of Group B (20.6±5.94%), suggesting that the runners with higher running power had superior leg muscle endurance. The present results suggest that in order to improve the performance of the runners who participated in this study, it is likely to be necessary to implement training aimed at improving leg muscle power (HSJmax higher than 35 cm) and leg muscle endurance (HDI lower than 13.6%).

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For the advancement of Japan’s global human resources in sport and physical education, English language learners must have greater access to authentic and relevant language learning resources. Through analyses of audio and video recordings of instruction at ice hockey player development and conditioning camps in Canada between 2010 and 2013, common and recurrent language was identified and applied in sports English language lessons targeting the natural production of the target language. This particular lesson, based on a 2010 recording, aimed to confirm the assumption that learners would demonstrate increased motivation, attentiveness and natural language production through language learning activities based on these authentic materials. During the lesson, learners were observed to apply various combinations of the target language in performing original instruction, and demonstrated the transfer of linguistic and sports-based comprehension in completing the activities. For future study, the lesson needs to be attempted with additional classes and learners of varying ability, and needs to include native English speakers among the Japanese learners in order to more accurately evaluate the Japanese learners’ actual English communicative proficiency.

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The present study aimed at examining the feedback effect obtained with a method in which the ground reaction force was presented as vector, in comparison with the conventional method. The participants were two university baseball players. They did tee batting in the laboratory in two ways, and then were asked to comment on the ground reaction force. The player who did not know anything about ground reaction force could not understand either graph. On the other hand, the player who knew about ground reaction force could understand both graphs well, and made many comments. These results suggest that a batter’s knowledge about ground reaction force is likely to have a large influence on the effects of feedback about ground reaction force during batting, such that feedback is likely to have a different effect on time-force graphs and vector graphs, depending on the player’s understanding of ground reaction force.

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The present study evaluated effects of the session rating of perceived exertion (RPE) method in relation to an amateur marathoner’s daily training, including various indices of his condition and his race performance. The participant was an amateur marathoner (age: 23 years old; height: 173.5 cm; weight: 50 kg) who had finished a marathon in less than 3 hours. He participated in marathon races twice, in November 2013 and February 2014. The record of his training for 9 weeks before those races was evaluated in terms of load, monotony, and strain, which were calculated using the session rating of perceived exertion method, in addition to the distance run. Furthermore, his weight, body fat percentage, number of hours of sleep, and heart rate at the time of awakening were measured daily as indices of his condition. Based on the observed changes in load and strain before each race, the session rating of perceived exertion method was judged to be an effective measure for evaluating effects of amateur marathoners’ training.

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One of the techniques in parallel bars in gymnastics is “swing forward, straddle cut backward, and regrasp with the body straight and horizontal”. This technique, developed by Raj Bhavsar in 2009, is generally called “the Bhavsar”. It is ranked at the E degree of difficulty. At present, at when gymnasts are being coached, athletes who have mastered the Tippelt then start to learn the Bhavsar. This is because the motion leading to the final position in the Tippelt has a problem. Ideally, it should be a handstand, but many athletes complete the handstand after forming a straddled L-sit position. Also, this posture is accepted as a technique at most competitions. This means that the Bhavsar, where the hang is completed by regrasping with the body straight and horizontal, is more difficult to acquire than doing an immature Tippelt, in which the handstand is completed after a straddled L-sit position. Therefore, when learning these moves, the Bhavsar should come after the Tippelt. The present study, which was conducted with 1 participant, aimed to convey this finding to coaches, and suggested motion differences in the hang, tap, and open-chest phases, based on a comparison of the Tippelt and the Bhavsar.

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Trampolining is a sport in which athletes compete in 10 jumps on jumping height and stability. At present, although there is an evaluation index for jumping height, no stability index exists. The present study aimed to develop an index for evaluating jump stability. Videos of actual competitions were used to quantify the landing position on the bed by means of a two-dimensional direct linear transformation (DLT) method for 14 athletes who performed 10 front and back rolling jumps in the same order, and to calculate longitudinal (front-back) and transverse (left-right) elements of the travelling distance (D) and the distance from the center (DC) in those 10 jumps. The results suggested that in the higher group, elements of the travelling distance and its longitudinal elements, and distance from the center and its longitudinal elements, were significantly smaller. Further, negative orrelations were found between elements of the travelling distance, distance from the center, distance from the center’s longitudinal elements, and the execution score (E score). These suggest that jumping stability can be evaluated in terms of the size of the travelling distance and the distance from the center, particularly the longitudinal element, during jumping. In addition, in the present study, these indices were applied to evaluate effects of training aimed at improving jumping stability. Training in maintaining the body vertical and in jumping and landing in a straight line was given to 7 high school trampoline athletes. After the training, their distance from the center and their distance from the center’s longitudinal elements became significantly smaller, which suggests that the training may have had an effect.

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Yuichiro Miura, a professional skier, is a record-setting alpinist who climbed to the top of Mount Everest (8,848 m) at the age of 70, 75, and 80 years. For the past ten years, Miura’s cardiorespiratory function, muscular strength, and overall physical fitness have been being measured at the National Institute of Fitness and Sports in Kanoya. Recently, a Balance Master Platform System (NeuroCom International, Clackamus, Oregon, USA) was used to measure Miura’s static and dynamic balance ability. Sway velocity (deg/sec), btained while a person is standing on a soft foam pad placed on the measuring platform, quantifies the participant’s center of gravity (COG). Miura’s sway velocity (SV) was 1.8 deg/sec. This value is similar to the average sway velocity of 20- to 30 year-old men, indicating that Miura has maintained exceptional static balance compared to age-related norms. A Limits of Stability (LOS) task was used to measure Miura’s dynamic balance. The Limits of Stability task quantifies the maximum distance that people can intentionally displace their center of gravity, i.e., lean their body in a given direction without losing their balance, stepping, or reaching for assistance. The measured parameters are reaction time (RT), center of gravity movement velocity (MVL), directional control (DCL), end point excursion EPE), and maximum excursion (MXE). Miura’s end point excursion was 86%, a very high performance for someone of such an advanced age (compared to age-related norms). His center of gravity, directional control, enter of gravity movement velocity, and maximum excursion were also superior compared to age-matched norms. It is hypothesized that the repeated adjustment of his posture while climbing through narrow trails in the Alps and other high mountains, combined with a lifetime of mountain skiing, has contributed to Miura's ability to perform at a high level with respect to both static and dynamic balance, even at the age of 80.

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The present study examines “mental training” for U17 All Japan Rugby Football players who were called up for the first time as a team just a few days before the 17th Junior Exchange Games between Japan, China, and Korea. In this case, the team’s coach had been getting anxious because the players did not display aggressive behavior during practice at their training camp. Only 4 days remained available for providing “mental training”, in which a consultant provided psychological skill training for the team, so the usual points involved in long-term training were narrowed down to the following: (1) Effects of short term mental training, (2) Improving the team’s attitude (team building), and (3) Increasing their self-confidence. In small-group discussions, the athletes were encouraged to solve the team’s problems. After this short-term psychological skill training, the athletes gained confidence, developed team solidarity, and eventually won the championship. Thus, an intervention with mental training for teams organized in a short period of time, such as this national team, might be able to have an effect within a very small amount of time.

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In order to build a reference for future volleyball coaching, the present authors examined how a university women’s volleyball team would react to a method of coaching that emphasized approval. The coaching method was implemented with the NKU University women’s volleyball team during the 2012 spring and autumn league competitions. The following were observed: The players decided on slogans for use outside of the court, at practices, and at games. All the participants were members of the team, which led them to think spontaneously about how they could contribute to the team’s wins. Specific goal setting and team building by the players generated solidarity, which led to strengthening the bond among the players. The players trained in order to improve their low side-out percentage. By setting a clear goal, even though the number of perfect pass points decreased, the side-out percentage increased from the spring to the autumn competitions. When the players trained, they bore in mind that the team had tended to miss often. After acknowledging this tendency, the miss points decreased, as was shown when the results in the spring competition were compared to those in the autumn competition. By analyzing data from the scrimmage and competition results, the players were able to evaluate their performance objectively. The coaching method emphasizing approval appeared to have good results.

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The present study reviewed a method of improving the serve of a university woman volleyball player so that the path of her serve could not be read by her opponents. In an attempt to improve her serve, differences between straight shots and cross shots were first identified by a three-dimensional analysis. Significant differences were observed in her body’s position front to back and left to right. In order to eliminate those differences, she practiced for 5 months on the following: (a) keeping the tossing position constant, and (b) shooting from a higher position so that the ball passed as close as possible to the upper edge of the net. After that, subjective evaluations by the libero included opinions such as “the ball’s path became clearer” and “the ball’s speed became faster”. Furthermore, in the Autumn league, after her improvement, although the effectiveness rate of her serves dropped, the number of clean (no touch) aces increased. An examination of these results suggested that practicing getting the ball to go as close as possible to the upper edge of net had the unexpected consequence of her keeping her tossing position constant, which in turn resulted in her serve becoming difficult for her opponents to read.

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When pitching, player A (age: 11.7 years, height: 156.1 cm; weight: 40.5 kg) had a small rotation range of his pelvis from the stride foot making contact with the ground (SFC) to the ball being released (REL). The present study attempted to improve his pitching motion by controlling the rotation of his pelvis just after SFC, using two different training methods: (a) pitching practice with technical coaching, and (b) pitching training using an inclined board. Ball speed and pitching motion were measured. In post measurement I (after practice with technical coaching), the ball speed did not change, whereas at post measurement II (after training with an inclined board), the maximum ball speed was 89.0 km/h, which was an increase of 1.0 km/h (1.1%), and the average ball speed increased by 2.0 km/h (2.3%). Also, after using the inclined board, the pitcher achieved aimed control of his pelvis rotation until he landed on the stride foot. Data from measures of the ground-reaction forces showed that 1) the throwing direction on pivot leg increased, 2) the reverse direction of pitching on stride leg from the maximum rotation of his shoulder to REL increased. These results suggest that the ball speed increased because of the improvement in the trunk rotation, which he achieved by controlling the rotation of his pelvis until SFC, and the twisting motion, as well as increased energy, that was generated by his lower limbs. Training an elementary school pitcher using an inclined board may be an effective method for controlling the rotation of the pitcher’s pelvis and generating the ground reaction force on his lower limbs.

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The present study aimed to examine the influence of vaulters’ intention with respect to their performance of the Kasamatsu vault. In the present study, 4 university male gymnasts with different styles executed the Kasamatsu stretched with a 1/1 twist. Their vaulting motions were filmed with a high-speed digital camera, and then compared and analyzed. One of the gymnasts who had a side-rolling style did not make the second touch until his body had swung up and become straight from arm to toe. Because of that, his foot moved ahead of the position of his body and the releasing hand was slightly closed. On the other hand, another gymnast who had a front rolling style touched with one hand for a shorter time, and released his hand with a straight posture near the vertical position by using a strong blocking action of his upper arm when touching. These observations suggest that vaulters may be able to have a more effective pushing motion and achieve greater height by using a front rolling style rather than a side rolling style.

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Oriented control play in soccer, which an offensive player receives the ball while facing the opponents’ goal, is important. However, there was no earlier finding which quantified oriented control plays during matches with relation to wins and losses. The present study aimed to elucidate effect of number and appearance ratio of oriented control plays on wins and losses of the matches. Participants were collegiate soccer players. Their official and practice matches were recorded with a video camera. From the obtained films, the number and appearance ratio of oriented control plays, and the number of shoots within the opponents’ goal, which is an index of effective offense, were counted for each player. The results revealed that the number of oriented control plays was higher in win matches than in draw or loss ones. The appearance ratio of oriented control plays was also higher in win and draw matches than in loss ones. The number of shoots within the opponents’ goal was positively related to the number and appearance ratio of oriented control plays with median effect size. These results indicate that the number and appearance ratio of oriented control plays is higher in win match compared to draw or loss match.

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The present study developed a training program for Player A, an elementary school student, whose pitching motion had problems such as too small a rotation of the trunk of his body (no turning backwards on take-back), too small a bend of the trunk of his body when releasing the ball, and too big an internal turning of his shoulder (compensation motion due to lack of an extension motion of his elbow joint). The present study evaluated effects of a training program aimed at increasing ball speed and preventing pitching-related injuries for Player A. The program included training that utilized the rotation of the trunk of his body (pitching exercise from a sitting position) and training connecting the motion of his lower leg and the trunk of his body (Mashitanage training). After this training, Player A’s maximum ball speed increased by 1.7 km/h (1.7%), and the average speed of 5 pitched balls increased by 3 km/h (5.4%). After the training, Player A’s pitching motion changed as follows: the extent ofhis turning the trunk of his body backwards before landing on the step-in foot from　the lowest position of the ball during the cocking period became larger than before the training, and the movable range of the trunk of his body during the acceleration period (from the landing of the step-in foot to releasing the ball) also became larger. The bending motion of the trunk of his body when releasing the ball became larger, and the swinging motion of his upper arm became smaller because of his extending his elbow joint on releasing the ball and having a smaller internal turning of his shoulder joint. These results suggest that this training program may be effective for improving the backward turning of a pitcher’s shoulder before landing on the step-in foot, the turning of the trunk of the body in the acceleration period, the bending motion of the trunk of the body on releasing the ball, and the swinging motion of the upper arm. The results with Player A suggest that this training program may well be a useful method for quickly improving the movements of baseball players who have problems because the turning motion of the trunk of their body is too small, the bending of the trunk of their body is too small, and the internal turning motion of their shoulder is too large.

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The present study aimed to examine effects of naginata training in which the distance between the naginata blade and the athlete’s body was limited by having the athlete stand by a wall when practicing the hasso sune strike, in order to improve the side swing motion. The participants were 7 university female naginata practitioners who practiced under set conditions at different times with and without a limitation. In the condition with a limitation, the distance from the wall was set at 65 cm. The participants practiced hasso sune strikes from that position, with the goal that the naginata blade would not hit the wall. In the condition without a limitation, they practiced as usual. In the experimental training, they did hasso sune strikes 100 times, repeating that 12 times, 3 times a week for 4 weeks. The results from the limited condition indicated that the variation of the x-axis of the naginata blade was significantly reduced (p<0.05), and the athlete’s distance from her opponent and the forward element of the force of her left leg against the ground significantly increased (p<0.05). These results suggest that the training that limited the distance between the naginata blade and the athlete’s body was effective in improving the side swing motion by reducing the distance between the naginata blade and the athlete’s body, and that it also improved the distance between the opponents.

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