In many ball games, as the competition level increases, the intensity of movements such as physical contact and acceleration/deceleration characteristic of that game increases, with the result that the motor output and physiological response increase. These phenomena can be measured only in a game in which a team is playing at a high level of competition. However, reports of quantitative changes in these measures have not been published. The present study examined the exercise and physiological responses of basketball players who were accumulating loads in the second half of a game involving a high level of competition. In the first half of the game, although the game was at a high level of competition (i.e., against a professional team), the players’ exercise output level tended to increase, but their heart rates were not related to the level of competition of the opposing team. However, in the second half of the game, although the players’ moving distance/speed was maintained at a high level against the professional team, the frequency of high acceleration in relation to participation time decreased in 3 of the 4 players measured. Furthermore, the minimum heart rate after the heart rate had reached a maximum increased (that is, the recovery of the heart rate decreased) in both of the 2 players measured. Due to small number of players measured in the present study, players in more games should be measured. However, the present results suggest that the indices measured may be indicators of the physical/physiological load occurring in games that are at a high level of competition.

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Much has been published about how to coach the straight leg forward roll on the mat, but further study of coaching and training methods for the acquisition and mastery of this movement is still necessary. The present study involved actual coaching of straight leg forward rolls on the mat with one elementary school student who was at step 1 and two who were at step 2, with the aim of collecting useful information about training methods that would assist students to acquire this technique. After they were coached, the acquisition level of each of the students improved with respect to the motion of opening the angle of the hip during straight leg forward rolls. This suggests that the present training method may be useful for helping novice gymnasts acquire and master the motion of opening the angle of the hip so that the motion of their legs is transmitted to their upper body during straight leg forward rolls.

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The present study examined the influence of the number of steps in the approach run on performance of the triple jump. The participant was a university male triple jumper. His jumping performance was measured by a pressure running board that could measure continuous performance over 50 meters. The measures obtained were the speed of the approach run, his hop, step, and jump performance, changes in the distance jumped, his holding time, speed, ground reaction force, and impulse force, when the number of steps in the approach run was gradually increased from 2 to 18. Linear regression analysis was used to find the number of steps for which the relation between the length of the approach run and his jump performance became critical. The results suggest that the following points should be taken into account when practice for the triple jump includes a gradual increase in the number of steps in the approach run: 1) The influence of the number of steps depends very much on the kinematic variable when the number of steps is fewer than 8 (approximately 15 meters) or more than 12 (approximately 25 meters). 2) When the number of steps is 8 or fewer, the variability of the jump performance will changed greatly in relation to the number of steps. 3) When the number of steps is 12 or more, there is not much difference due to the number of steps compared to a full-length approach. 4) Reduction of the horizontal speed must be minimized at the take-off of the step and the jump, and it may not be necessary to raise the body vertically by acceleration.

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The present study describes the rehabilitation of a male gymnast who aimed at returning to still rings events after surgery for a dislocated shoulder. Examination of the gymnast included motion electromyogram of the muscles surrounding his scapula (the trapezius and serratus anterior muscles) during the movements involved in hanging handstands and still rings exercises. The wave forms obtained from the electromyograms on the affected side were compared with those from the unaffected side. No pattern of gradual increase or decrease was observed for his adductor muscles (the upper and middle fibers of the trapezius muscle) or abductor muscles (the lower fibers of the trapezius and serratus anterior muscles) during hang and still rings movements. He then did exercises in order to regain the pattern of gradual increase or decrease of the adductor and abductor muscles, such as abductor and adductor motions of the shoulder joint while holding a weight in a lateral position. After doing this exercise, the gymnast became able to perform the still rings exercises. When his performance before and after the rehabilitation exercises was compared, an improvement in the motion pattern of his muscles during the still rings movements was found. These results suggest that the rehabilitation of gymnasts who aim to return to the still rings after an operation for a dislocated shoulder may require them to regain a smooth pattern of motion of the muscles surrounding the scapula, in addition to strengthening those muscles.

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The present study examined the effect of low-load full-power pedaling training on the running ability of 4 ballgame players. In the training, the participants used a full-power pedaling motion under a load of 1.0 kp for 7 seconds. This was repeated 5 times per set, 2 sets x 3 times per week, for 4 weeks. The participants’ running ability was evaluated from their 25-meter run time and their pitch and stride in the 0-10 meter portion of that run. The results showed that 3 of the 4 athletes improved their 25-meter run time. When the participants’ scores before and after training were compared, it was found that each of them showed different changes in pitch and stride in the 0-10 meter portion. These results suggest that the low-load full-power pedaling training may have been effective for those athletes who were low in pitch at the start of the dash and for those who were low in acceleration in the latter half of the short sprint, whereas it may not have been effective for those athletes who were superior in pitch at the start of the dash prior to participating in the present training.

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The goal of the present study was to obtain a quantitative evaluation of the pedaling technique of cycle road racers by using a cycle ergometer called “Wattbike”, made in the UK, that is capable of measuring the force applied to the chain. The participants were 8 university students, including 3 cycle road racers, 3 track cyclists, and 2 inexperienced cyclists. The participants pedaled at various power levels with a fixed speed of 95 rpm. Compared to the track athletes and the inexperienced cyclists, the road racers’ maximum force (Max. F.) to the chain at the same power level tended to be lower, whereas their minimum force (Min. F.) tended to be higher. When the participants’ coefficients of variability, as indices of maximum and minimum force, were calculated in order to evaluate pedaling reproducibility, the road racers’ coefficients were found to be the lowest. This suggests that these indices may be applicable to the quantitative evaluation of road racers’ technique, and that a training program could be designed based on these results.

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The physical fitness of young children in Japan has been decreasing continuously. In particular, their coordination abilities are poorly developed. The present study examined the achievement of “line training” (the Japanese term for an exercise involving skipping or jumping to one side and forward, parallel to a line), which is used in preschools as a convenient, practical exercise to train coordination. The participants in the present study, 15 five-year old children (8 boys and 7 girls) who were attending a private preschool in Hyogo Prefecture, were given one month of pretraining and 10 weeks of the main training. In the first 5 weeks of the main training, they did basic steps of line training; in the latter 5 weeks, they did practical steps for 20-30 minutes per time each week. The children’s progress was evaluated every week by rating their level of achievement on a 4 point scale (0~3). The results showed that, in the first half of the training, the children’s achievement of basic steps significantly improved. More than 80% of the children were rated at level 2, in which the tempo of stepping is not stable but stepping can be completed without mistakes. In the latter half of the training, all the children acquired more than 10 kinds of basic and practical steps. These results suggest that basic and practical steps in line training may be a useful method for improving preschool children’s performance, enabling them to acquire various steps in a short time.

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When martial arts became compulsory in junior high school health and physical education classes, about 64% of schools choose judo. Of the various ukemi (passive) judo techniques, the front rolling ukemi takes students the longest time to learn. To deal with this situation, the present study proposed a new method for coaching front rolling ukemi. Participants in the study were university physical education students who were beginners in judo. Their inaccurate motions were classified into two patterns, a “plunge type” and a “side-fall type”. To deal with the plunge type of error, a “red string method” was used, in which both sleeves of the judo gear were tied back with a red sash to prevent the student’s head from plunging onto the tatami, similar to front rolling in gymnastics. To deal with the side-fall type of error, a “long stick method” was used, in which the student rolled forward while holding a long stick in order to force the correct sequence of contacting the tatami during the roll (little finger – wrist – elbow – shoulder – hip – leg). When the red string method was used, because the line of the student’s sight was fixed and his neck was twisted when rolling, hitting his head on the tatami was avoided. When the long stick method was used, the rolling motion was controlled and the sequence in which the student’s body contacted the tatami became accurate. The results from questionnaires suggested that both of these coaching methods resulted in the correct motions becoming automatic. The red string method may be an effective coaching method for plunge type errors, and the long stick method, for side-fall errors.

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The first author accompanied a baseball team composed of players from high schools in Kyoto Prefecture as a medical staff member when they visited Malaysia and Singapore. A visit to a tropical area requires countermeasures against exertional heat illnesses, but the relationship between the local heat environment and exertional heat illnesses was not known. The present study aimed to clarify this relationship and to evaluate the countermeasures used. Before the trip, a lecture about exertional heat illnesses was given to the 18 participating players, and a supporting function was established. During the visit, the weather and the players’ physical condition were checked, and the heat environment of the playing field was measured. Dehydration rate was calculated with the change in body weight before and after exercise, in order to protect against exertional heat illnesses. The WetBulb Globe Temperature (WBGT) was over 24 degrees C., which could have put the players at high risk of exertional heat illnesses, but none of them had exertional heat illnesses or was more than 3% dehydrated. Through the countermeasures against exertional heat illnesses, the players’ understanding about exertional heat illnesses improved, which resulted in prevention of exertional heat illnesses. The dehydration rate varied from player to player, depending on the WetBulb Globe Temperature, the humidity, and the time at which the players practiced, which suggests that it may be necessary to design countermeasures for each player individually.

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Softball is included in the government junior high school curriculum guidelines for health and physical education, and so games are held at schools. However, not all junior high school students enjoy softball, perhaps because the rules are too complicated to understand, or because the game requires skilled catching and throwing and the ability to judge situations, such as the optimum place to throw the ball. The present study proposes a structured modified game for beginners so that they can learn the rules of baseball-type ball games. The usual rules concerning base running and judging when a player is out, and the techniques of batting, catching, and throwing are so complicated that the game cannot be conducted smoothly by beginners. In addition, as the rules stipulate that players must run around all four bases to score, a game takes too long for beginners to be able to enjoy it. In order to avoid those complexities, a mini-game with simplified rules was devised and tested with beginning female softball players at a junior high school. Many of the girls participated actively, although some did not improve their catching or throwing technique, which is a remaining problem. The rules of the minigame should be improved further, so that defending techniques can be improved while playing a game.

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The present study compared the physical strength of two groups of university student kendoka, an upper group of 12 male experts with high competitive strength and a lower group of 12 males at the same university. The results revealed specific features of the upper group compared to the lower group, such as higher BMI and greater lean-body mass even in individuals of the same height, as well as superior reaction time and jumping ability, comparatively greater strength of grip (particularly on the left), back muscle strength, and knee extension strength (particularly on the left). The ankle plantar flexion strength (left and right) was relatively more developed. Features of the physical strength of the upper group were analyzed in relation to each athlete’s special skills. Those kendoka who were judged to be good at striking men from a distance, good at initiation technique, or good at the pulling-back technique showed localized development of the body areas used in each of those techniques. Furthermore, features (strengths and weaknesses) of these individual kendoka in competition were related to the developmental level of each individual’s physical strength. These results suggest that the improvement of the competitive strength of university kendoka must be done in consideration of (a) the average physical strength of those in the upper group, (b) the specialized physical strength needed in relation to each individual’s special skills, and (c) the characteristics of each individual’s ability and physical strength.

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The present study reports the results of training based on a plan-do-check-act (PDCA) cycle that aimed at improving the speed of balls batted by high school baseball players. The participants, 17 high school baseball players, received medicine-ball throwing (side direction) and isometric training of their batting motions in order to improve their batted ball speed. The training was conducted for 9 weeks, 3 times a week. Before and after the training, the ball speed when the players were tee batting and the speed of their practice-swings were measured. Comparison of the pre- and post-training results revealed significant improvements in batted ball speed (pre: 33.4±1.5 m/s, post: 34.6±1.6 m/s, rate of change: 103.6±2.9%) and swing speed (pre: 32.5±2.3 m/s, post: 35.0±1.7 m/s, rate of change: 107.8±5.2%). These results suggest that the training may have been effective in improving the batted ball speed. The discussion suggests that, in the annual training program, starting the training period earlier and adopting weight training for increasing muscle mass may also be useful ways to achieve further improvement.

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The present study was an experimental examination of the possibility of identifying the stepping-in sound in kendo in relation to various stepping-in techniques, in preparation for a study of kendo stepping-in sounds. The present study analyzed the sounds associated with 4 stepping-in methods common in the practice of kendo. The sounds tested were in the frequency range between 200 Hz and 4,900 Hz which are in the audible range, out of the full range of sound, which is between 20 Hz and 20,000 Hz. The results confirmed that the frequency spectrum of the stepping-in sounds differed, depending on the stepping-in method. This suggests that differences in the stepping-in sound can be identified objectively in relation to various stepping-in methods.

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The present study aimed to clarify the relationship between measured exerted force and swimming motion in front crawl swimming by elite Paralympic swimmers. The subjects were 5 swimmers with disabilities who had participated in international Paralympic competitions. Exerted force was measured in a water circulating pool with an improved method from previously published studies. After the swimmers were connected by wires to a load cell, they swam at full power for 10 seconds, so that the force exerted could be measured. There was a tendency for their force to vary left-right asymmetrically. Also, the athlete’s force increased when their upper arm went into the water after a recovery motion in the air. These results suggest that the tethered force-measuring method used in this study can be used to evaluate the swimming motions of swimmers with disabilities. Since knowledge of the swimming force of swimmers with disabilities is limited at present, the findings from this study can be a useful reference for improving the swimming motion of swimmers with disabilities.

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Analyses of videos of the flow trend in volleyball games that have been reported in previously published studies have more or less the same results, providing only ordinary information on the flow trend of the games. In a game, score differences can be as big as 5 points, but that difference may be reversed by the end of the game. In such cases, the flow trend of the game has not been understood. The present study aimed to examine the flow trend of a game by comparing the results of a close game with the results reported in previous studies. In the present study, the participants watched a video of a volleyball game and answered questions after every rally, as well as answering questions about the flow trend of the designated team’s game. Their judgments were given on an 11-point scale from -5 to +5, where -5 meant that they had observed no flow trend, and +5 meant that they had observed a strong flow trend. The results were as follows: 1. In previous studies, a loss of 2 consecutive points indicated a significant flow trend, but in the present study, a loss of 2 consecutive points with a 1-point reversal did not change the participants’ judgments of the flow trend. The results regarding losses of 2 consecutive points were the same as in previous research. 2. Participants’ recognition of a flow trend was influenced by the progress of the game. 3. In a close game, the same point difference was judged to have a similar flow trend. In other words, in a close game, the point difference predominated in judgments of the flow trend.

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The present study examined influences of wearing kendo gear that a kendoka felt was uncomfortable on the time difference between her striking and stepping-in. The participant was a female kendoka who was judged to have a deviation from her usual simultaneity between striking and stepping-in when wearing her own kendo gear. This resulted in her taking longer between striking and stepping-in when wearing kendo gear that she felt was uncomfortable than when she was not wearing that kendo gear or was wearing kendo gear that she felt was comfortable. This suggests that a reason for the prolongation of the time between her striking and stepping-in and the deviation from approximate simultaneity may have been that she was wearing uncomfortable kendo gear.

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The majority of injuries in classical ballet dancers occur in their knees or feet; groin pain is much less common. Regardless of the sport, rehabilitation methods for the groin pain are not well known. The present study reports the successful result of rehabilitation for a classical ballet dancer who had groin pain on her left side when doing a lateral grand battement, and suggests a method of prevention. The patient was a 29-year-old woman who had increased tenderness and muscle-tone in her tensor fasciae latae and rectus femoris muscles on the affected-side (left).In addition, when the hip was held in the external rotation and abduction position, excessive contraction and pain in the tensor fasciae latae and rectus femoris muscles were observed by palpation. Based on an evaluation of her range of motion and muscular strength, it was hypothesized that her pain was caused by compensation with the rectus femoris and tensor fasciae latae muscles for weakness in the muscles of the deep external rotator muscles and the iliopsoas. Then, facilitation of the deep 6 external rotator muscles, suppression of muscle tonus of the tensor fasciae latae and rectus femoris muscles, abduction in flexion, SLR (Straight leg raising), improvement of abduction and the external rotator range of motion , and facilitation and strengthening of the iliopsoas were conducted. Three months later, the pain in her left groin had disappeared. This result suggests that facilitation and strengthening of the deep 6 external rotator muscles and the iliopsoas may be important for preventing groin pain as a result of doing lateral grand battement.

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The present study aimed to identify reasons for failure and points related to success in the Yeo 2, a handspring front layout with 2.5 twists, in the vault, by comparing successful and unsuccessful vaults. The vaults of two gymnasts who attempted the Yeo 2 at the 2014 Toyota International Gymnastic Competition were recorded at 250 fps with two synchronized high-speed video cameras. The gymnasts’ motions from the on-board phase through the on-table phase were analyzed on a two-dimensional plane by projecting three-dimensional coordinates obtained with a three-dimensional direct linear transformation (DLT) method on a sagittal plane. The results showed that, in the unsuccessful vaults, compared to the successful ones, the gymnasts’ center of gravity was higher in the hurdle step phase, and the vertical speed of their center of gravity was smaller in the on-board phase. Also, in the unsuccessful vaults, the angle of their body in the on-table phase was greater, and the angle at which their knee was bent was smaller. Furthermore, in the unsuccessful vaults, they moved their weight a smaller distance in the on-table phase. These elements lowered their vertical speed in the on-board phase, and made it difficult for the gymnasts to keep their center of gravity high enough in the second air phase. These results suggest that, for a successful Yeo 2, gymnasts should make the hurdle step from a reasonably high position and should touch the vault with a clear upward motion.

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The present study examined effects of female professional baseball players’ finger motions during pitching on the velocity and spin rate of the ball. Four female professional baseball players pitched to a catcher who was 18.44 m away. Their pitching motions and the velocity of the balls were tracked by an optical motion-capture system. Ball spin was measured by a Doppler radar tracking system. The results showed that the maximum velocity of each part of the body in the pitching direction had a tendency to increase in order of elbow, wrist, and fingertips, and that, at the point of ball release, the velocity of the fingertips and the ball was almost the same. These results suggest that the velocity of the fingertips is an important factor in determining the speed of the ball. Furthermore, those players who made high-speed pitches showed a marked difference in the time of appearance of the maximum speed between the wrist and the fingertips. In addition, those players whose pitched balls had high spin rates had a high flexion angle of the finger joints immediately before release, and the angular velocity was high.

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The present study aimed to create basic materials for coaching menko (a Japanese card game) based on a two-dimensional motion analysis of the actions of male university students who were experts at menko, as recorded with a high-speed camera. The analysis revealed five features of the menko experts’ actions that were considered to be important points for coaching: (a) standing close to the opponent’s menko, (b) standing with the feet spread wide apart, (c) using the knee extensor when throwing the menko, (d) releasing the menko from a lower position, and (e) throwing the menko just under the releasing point. When using a gym mat and a commercially available rubber coaster, throwing menko at an initial velocity of 70 km/h was enough to flip over the opponent’s menko. Further, because the analysis of the items relating to the experts’ standing posture showed significant correlations with the other items analyzed, the results suggest that a proper standing posture may be important for the improvement of performance in menko.

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Pitching is a gross movement in which the energy generated by a shift in weight and rotation of the body increases through a chain motion in each joint, and is eventually transmitted to the ball. However, beginners tend to be too concerned about throwing the ball strongly, which can result in an excessive bend of their elbow and a throwing motion that depends on their upper arm, emphasizing the bending-extending motion of the elbow (hand throw). One cause of this is not incorporating the rotation of the trunk in the throwing motion. The present study examined effects of an intervention that involved training in catching balls, in which the bend of the pitching arm elbow was controlled. The participant was a male junior high school baseball player. After the intervention, the angle of rotation of his trunk increased in the pelvis and shoulders, the rotating angular velocity of his shoulders increased, and the maximum angular velocity came to appear immediately before the release of the ball. In association with those changes, the ball speed increased by 10%. These results suggest that the training on catching balls that included control of the angle of the elbow of the pitching arm may have been effective for acquiring the rotation of his trunk and a more desirable timing of his throwing motion.

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When catching balls, university baseball player A, who was an infielder, did not bend the hip of his pivot foot well; instead, he bent his lower leg deeply forward. This resulted in his center of gravity moving rapidly in the direction of his throw, and his catching accuracy decreased. In the present study, the ball player participated in a training program aimed at improving the motion of his hip when handling grounders. After his participation in the training program, his motion when catching balls changed such that the excessive forward bend of his lower leg was controlled and the bending of his pivot foot increased. At the same time, the time between his landing on his right foot and his catching the ball increased, and his center of gravity moved more slowly in the direction of his throw. Those changes were accompanied by an increased percentage of balls caught and also an improvement in his coach’s subjective assessments. These results suggest that this training program might have been effective in improving the catching motion of player A.

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Two studies were conducted with male university judokas, aiming to identify a simple method for assessing judoka’s explosive and endurance power by using an intermittent sprint pedaling test with a bicycle ergometer. In Study 1, 10 sets of repeating tests were conducted, with 5 seconds of sprint pedaling and 10 seconds of rest. Participants were 22 students who had been classified by their coach into two groups in terms of their explosive power, with 14 participants in the higher group and 8 in the lower group. Likewise, for the endurance power, 10 participants were classified into the higher group, and 12 into the lower group. The results of the explosive power assessed by pedaling were different from the coach’s assessment, but the results for the endurance assessed by pedaling were similar to the pre-test assessment by the coach. In Study 2, 7 participants engaged in judo matches for a maximum of 5 minutes. Drawn matches were extracted, and blood lactic acid (BLa) was measured. These results were compared with those from the pedaling test in Study 1. The values were almost equal, 13mmol/L. The present results suggest that the intermittent sprint pedaling test is not relevant for assessment of judokas’ explosive power, but that it may be useful for assessment of their endurance power. Furthermore, this exercise could be used to train judokas who need to improve their endurance power.

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The present study examined the feasibility of improving the record of a university woman long jumper whose results in jumping competitions had failed to improve due to her using an incorrect takeoff motion that depended too much on her knees. She used a new training method for her takeoff that changed her motion so that it depended on her hips rather than her knees. After of 6 months of training with this method, she acquired the new takeoff motion, and her results in the long jump improved from 5.39 m to 5.61 m. Furthermore, the rhythm of her approach on the runway and her aerial form also improved. These results suggest that the new training method may be a useful way for jumpers to acquire a hip-dependent takeoff and to improve their takeoff motion in the long jump more generally.

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The present study aimed to examine effects of training the trunk of the body, using a flat dolly, on the thickness of the trunk muscles. The participants were male student athletes who specialized in jumping and composite events at track and field competitions. The training was conducted twice a week for three months, from December, 2015, to February, 2016, for a total of 20 times. In the training, a flat dolly was used for 18 types of trunk training. The muscles measured were the abdominal rectus muscle, the external abdominal oblique muscle, the internal abdominal oblique muscle, and the transverse abdominal muscle. For the abdominal rectus muscle only, measurements were made at three points: under the second, third, and fourth tendinous intersections. In order to have a measure of effects of the training on the muscles, a two-element within-subject design was used. The results of an analysis of variance revealed that the main effects of measurement time and measurement location were significant, as was the interaction. The main effect of measurement time was significant at each location measured. The thickness of all muscles measured increased significantly after the training. The amount of change in the muscles after the training was significantly higher in the transverse abdominal muscle than in the abdominal rectus and internal abdominal oblique muscles. These results suggest that the proposed method of training with a flat dolly may be effective for increasing the thickness of the trunk muscles.

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本研究の目的は, 大学野球選手の30m 全力疾走中におけるピッチとストライドの特徴を明らかにすることに加え, ポジション別の違いから野球選手の30 m 走の特徴を検討することとした. 被検者は, 大学野球選手36 名 (年齢: 20.3 ± 0.9 yr, 身長: 173.7 ± 5.0 cm, 体重: 68.9 ± 5.5 kg) であった.被検者全員に対し, 30m 全力走を実施し, 5m 毎のタイムを計測した. また5m 毎に, 疾走速度, ピッチとストライドを算出した. その結果, 野球選手の30 m 走は, 10 m を通過するまでピッチとストライドがともに増加, 10-15 m 区間ではピッチを維持しながらストライドが増加, 15-25 m 区間ではピッチとストライドを維持, 25-30 m ではピッチが減少しストライドが増加した. また30 m 走における疾走速度は, 0-30 m および10-15 m 区間のピッチと有意な正の相関関係 (p < 0.05) を示した. そして30m 走タイムは, 外野手, 内野手, 投手の順に短く, 外野手は投手よりも有意に短かった (p < 0.05).これらの結果より, 野球選手の走力は, 攻撃場面においてより重要な役割を果たす内野手や外野手が投手よりも優れており, 30 m 走が速い野球選手は, ピッチが一定となる10-15 m の区間にピッチを増加させることで効果的な加速を生み出すことが明らかとなった.

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Ki-ken-tai-ichi (unity of spirit, sword, and body) is essential for making effective strikes in kendo, and harmonizing the motion of the arms and legs is also required. With respect to the timing of strike with the arms and step-in by the legs, beginners tend to step in first and then strike, whereas experts strike first and then step in. Recently, young kendoka tend to make too much effort, so that there is a large time gap between strike and step-in. The present study examined effects and usefulness of changing the striking method to a leg-initiation type, in order to diminish the time gap between strike and step-in when frontal striking. The participants were 60 university kendoka of 3- to 4-dan level; the trainer was a 7-dan kendo expert. He first gave a lecture and demonstration, then conducted once-thru training for 30 minutes to correct the participants’ method of striking. An immediate effect of a significantly diminished time gap between strike and step-in was obtained. This effect was greater in those kendoka who had had a bigger time gap. This suggests that the leg-initiation strike may be useful for diminishing the time gap between strike and step-in. Also, it is possible that acquisition of (and habituation to) the leg-initiation strike may make it possible for kendoka to acquire the basic motion of men technique by unifying offense and strike against the opponent.

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The aim of the present study was to collect practical information useful for improving cyclists’ pedaling technique in cycling competitions. Effects of a hip pedaling technique drill on the solid feeling, pedaling motion, and pedaling power of university cyclists were examined. The hip pedaling technique (HPT) was compared in a constant power demonstration to a preferred pedaling technique (PPT) that the participants, university cyclists, had already been using. The results revealed differences between the hip pedaling technique and the preferred pedaling technique in the cyclists’ pedaling motion and solid feeling. The hip pedaling technique may result in more compact and efficient motion of the lower legs when pedaling than the preferred pedaling technique that these university cyclists had been using.

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Three-dimensional motion analysis systems for studies of kinematics and the kinetics of body motion have become increasingly popular and are more often used in recent years. However, concerns about the use of this system include its high cost and the delay in feedback to both the players and the coach and other staff on the field due to a high-effort analysis time. The present study reported on the development of a loweffort, quick-turnaround body motion analysis system utilizing an economical device, i.e., a home digital video camera. After moving images of sport motion and performance data are inputted into the system, image processing and statistical processing are both done automatically, and image data (information) useful for improving the players’ performance are displayed. Players can practice using this information. Their performance is expected to improve in stages because the system gives visual feedback to them quickly. The present paper reports a demonstration of this newly developed system of motion analysis as applied to the serve of a male junior tennis player. After the athlete had continued to practice his serve using this system for three months, it was possible to see improvement in the motion of his service.

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The present study aimed to develop a method of evaluating infielder’s speed of handling grounders, and to examine the utilization of that method at a coaching site. The participants were 40 infielders who threw right-handed and who were members of baseball teams in high schools and universities. In the study, a participant stood at the regular shortstop position, and baseballs were placed at 7 different positions 5 meters away from the participant (in front, diagonally in front to the left and the right, on the left and right sides, and diagonally in back to the left and the right). At a signal, the participant caught a baseball coming from a pre-indicated direction and threw it to first base. This motion was filmed with a high speed camera, and the time from the start to the end of the player’s motions was measured. In addition, the player’s foot placement during this period was analyzed. The results indicated that the players’ average motion time for balls coming from all the directions tested was similar to the average ball-throwing time when a ball is batted toward the shortstop in regular university baseball games. Since the motion style and the motion time measured in the present study were very similar to those used when handling grounders, the present measurement method may be applicable for evaluating the speed of handling grounders. Coaching aimed at reducing the number of steps that players take when catching and throwing the ball may also be effective in reducing the time taken to handle grounders.

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The present study reported and analyzed changes in the form of a male shot putter’s movements and the awareness of his movements in the rotational shot put. The athlete’s efforts could be divided into four periods. The form of his movements and his awareness of his movements changed as his shot put results changed. In addition, in the fourth period, when continuous change in the form of his movements was reorganized into observation points and the purpose of his movements into kinesthesis, the items were transformed into 9 movement-form items and 10 movement-intention items. This analysis produced three stages in the development of the rotational shot put: learning to turn, learning how to deliver, and accelerating the body while turning. In order to understand the form of the athlete’s movements and the intention of his movements, he was observed when he was training for shot put competitions, and changes in the distance achieved were noted.

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Problems with the batting motion of player A (22 years old; height, 166.1 cm.; weight, 60.0 kg), according to his self-examination, were that, when batting, he moved his upper body with the result that his body weight shifted ahead too much, and that he found it difficult to grasp the correct timing for batting. The purpose of the present study was to examine effects on the accuracy of his hitting of using an inclined step in batting practice that had the purpose of correcting his upper-body motion. His batting average during games and his motion when tee batting were recorded. After four weeks of this training, the speed of his swing did not change, but his batting average improved from .200 (1 hit in 5 at-bats) to .364 (4 hits in 11 at-bats). Also, his batting motion improved in that the distance through which his weight shifted toward the batting direction in the stepping and swing phases decreased. This suggests that, because of the decrease in the shift in his weight, his timing improved and that, in turn, resulted in the improvement of his batting performance. These results suggest that batting practice with an inclined step may be an effective method to use with baseball players who, when batting, tend to move their upper body excessively and have difficulty getting their timing right.

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A sprinter who is a student at a sport university ran the 100-meter dash in 11.10 seconds when he was in his senior year in high school. However, he was not able to achieve that result again until he was in his junior year at the university. After he joined a training camp in March of his junior year and various measurements were made to analyze his running ability, it was found that he had some deficiencies compared to other sprinters who were running at the 10-sec level. Then he took various countermeasures and succeeded in improving his record to 10.96 sec in August of his senior year and, further, he achieved 10.94 sec in September. The present study aimed to identify changes in elements of his running performance in the period in which he improved his results from the 11-sec level to the 10-sec level, and to collect information useful for field training. The results confirmed that his maximum running speed, which is the basic element of racing power, increased right before he ran the dash at the 10-sec level, and other improvements were also found in his running posture, his physique, the muscle power in his legs, and his jumping ability. In particular, large improvements were observed in his rebound jump and standing 5-step jump. These results suggest a new training program for sprinters who are aiming at running at the 10-sec level in the 100-meter dash.

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The present study aimed to describe the throwing motions of 1st through 6th grade boys and girls, using data obtained with a high speed camera that enabled a two-dimensional analysis of their movements. The results were as follows: The boys in the higher grade levels remarkably improved their motions by using a non-dominant hand and a rational motion of their legs and trunk. This resulted in the ball leaving their hand earlier and an increase in the initial speed of the ball. In contrast, the girls, even in the higher grades, did not progress sufficiently when using a non-dominant hand or in the motion of their legs and trunk. The initial speed of the balls that the girls threw remained at the same level as that of the boys in the lower grades, and the speed of the balls they threw was lower than that of the oldest boys. Those observations suggest that when coaches are teaching elementary school students to throw balls, it is important to have them shift the point at which they let go of the ball so that it is earlier in the period from early cocking to acceleration.

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The present study measured the location coordinates, wind direction, and wind velocity during speed training in the same sea area of three RS:X-class windsurfers, A, B, and C. Using the collected data, velocity, angle, and VMG (velocity made good) were calculated in order to identify features of those sailing indices in relation to differences in the windsurfers’ competitive levels and the wind velocity. The results were as follows: 1. The higher a windsurfer’s competitive level, the higher his VMG (windsurfer A> B> C). High VMG can be obtained by keeping the velocity high and the angle as small as possible (around 45 degrees) within the range in which velocity is not extremely decreased. 2. The three windsurfers showed equally high VMG in the 3-m condition (wind speed 3-4 m/s) compared to the 2-m condition (wind speed 2-3 m/s). No differences were found in angle. 3. Windsurfer B’s sailing angle was equivalent to windsurfer A’s, but his sailing velocity was lower, with the result that his VMG was lower. In the future, he should increase his velocity. 4. Windsurfer C, compared to windsurfer A, had a lower velocity and a larger angle in the 2-m condition (wind speed 2-3 m/s), and the equivalent velocity but a larger angle in the 3-m condition (wind speed 3-4 m/s). This resulted in a lower VMG. In other words, which sailing index (velocity or angle) needs improvement will be different, depending on the wind speed.

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The present study reports the training methods used by a woman middle-distance cyclist who established the Japan junior record of 2 min 35.98 sec in the bicycle 2-km individual pursuit when she was in high school, and who, in 5 years at university and in graduate school, improved her record in the 3-km pursuit race to 3 min 43 sec 259, which is very close to the Japan record. She also participated in many international races. The present study examined her past training in an attempt to identify possibly useful findings for training other cyclists. The period of this analysis was split into four stages, based on her 3-km pursuit race results and past training methods. Stage 1 was when she was in high school, Stage 2, road training; Stage 3, road training + assistance training that had been used in Stage 1; and Stage 4, road training + assistance training of the training that had been used in Stage 2. One of the goals of Stage 1 was to strengthen her cardiopulmonary function by using interval training when she trained on road and banked track. In Stage 2, her time was improved when she adapted to the training environment of her university. Track practice and weight training were introduced in Stage 3, but no meaningful improvement was obtained. In Stage 4, after she had had two serious injuries, her awareness changed and she realized that she had to do more strengthening training, such as track practice and weight training. After that, her results improved and became stable. These observations suggest the importance of well balanced training in addition to road practice, and of racers’ awareness of the impact of various training methods on their performance.

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The present study quantified behavioral characteristics of sports coaches based on the concept of competency, and examined those characteristics in women’s softball coaches who had produced excellent achievements. First，three world top-level women’s softball coaches were interviewed. Based on items extracted from those interviews, a questionnaire was devised. Subsequently，women’s softball coaches at top-level senior high schools and universities in Japan completed the questionnaire. Factor analysis classified “ competency scales of women ’ s softball coaches ” into “ observation ” , “ morale ” , “ communication ” , “ enlightenment ” , “ strategy ” , “ motivation ” , “ basic training” and “organizational management”. The women’s softball coaches who had produced excellent achievements observed players’ character and personal change, and gave appropriate advice and technical coaching based on their observations. Because these coaches who had trained many valuable players regarded strategy and morale, in addition to observation, as important, other coaches should encourage their players’ enthusiasm for continuing to play and for improving their athletic performance．

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In martial arts such as kendo and naginata, the effectiveness of striking is judged by referees from the viewpoint of ki-ken-tai-icchi (unity of spirit, naginata, and body). The present study quantitatively evaluated licensed referees’ judgments of the performance of ki-ken-tai in naginata, using the Visual Analog Scale (VAS). It was also aimed at obtaining suggestions for coaching. The participants were 9 university women naginata athletes. They executed striking 15 times each with 4 kinds of strikes. Each strike was evaluated by 3 referees on 9 criteria, consisting of ki, ken, and tai, using a 100-mm Visual Analog Scale. The results indicated that the evaluation values of ineffective strikes were significantly lower than those of effective strikes on all criteria. In particular, the values for accuracy of striking position and weight of striking for the ineffective strikes was considerably lower than for effective strikes. This result was common across all 4 kinds of strikes. This means that when judging the effectiveness of striking, the referees gave more weight to two items: accuracy of the striking position and weight of striking. The present results suggest the following points: 1) the performance of ki-ken-tai can be measured quantitatively with the Visual Analog Scale, and 2) the effectiveness of striking can be improved by improving the accuracy of striking position and the weight of striking.

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