This paper considers changes in basketball shooting techniques from the Taisho Era (1912-1926) through the first half of the Showa Era (1926-1989), focusing on technique history with special reference to the process of introduction of the one-hand shot. The results of this investigation can be summarized as follows. 1. From the Taisho Era to the early Showa Era, a chest shot using both hands was the main technique for shooting from middle and long distances. This technique was used as it was thought to be difficult to block. Eventually, however, defects of this shooting technique were pointed out, including a low rate of scoring. As for short-distance shooting techniques, these were thought to be divided into those where a shot was released after the player had made a stop, and a “running” shot. In the early Showa period, both of these were made with a one-hand shot, as this meant a higher possibility of scoring and avoiding defensive maneuvers. 2. The one-hand shot from middle and long distances was introduced in the early 1945-1954 period as an American technique. However, it was thought that it would be difficult for short-height Japanese to master this technique. In 1950, however, a Hawaiian “Nisei” (second-generation Japanese-American) team having the same body proportions as native Japanese visited Japan and demonstrated the one-hand shooting technique. This suggested that Japanese persons, too, would be able to acquire this technique. In Japan after the visit of the Hawaiian team, use of the one-hand shot for middle and long distances became widespread. Compared with the shooting techniques used in Japan previously, as this technique enabled higher scoring and quicker movement, it was characterized as being difficult to defend against, even when the defensive player was close in.
The purpose of this study was to investigate techniques for accelerating the hammer head in the turn phase of the hammer throw by comparing the motions of hammer throwers. Ten male throwers (PB: 43.15-68.21 m) participated in the study. The hammer motions were videotaped on high-speed VTR cameras (250 or 200 fps), and three-dimensional coordinates were calculated using a DLT method. Various kinematic parameters were calculated, including the hammer head speed, the increase in hammer head speed at each turn phase, the leading distance of the handle (hand), the horizontal abduction/adduction angle of the left arm (shoulder), the twist angle of the trunk, the rotation angle of the pelvis, and the horizontal abduction/adduction angle of the left hip. The fundamental factors and techniques responsible for accelerating the hammer head were as follows: (1) Increasing the acceleration and decreasing the deceleration of the hammer head in the turn phase increased the release speed of the hammer head. (2) A longer positive leading distance of the handle (hand), defined as the distance from the handle to the line connecting the hammer head and the instantaneous center of rotation of the hammer head, had a larger effect on the acceleration of the hammer head in the turn phase. (3) The horizontal abduction of the leading arm (shoulder), the negative trunk twist (recoiling motion), and the sway motion at the midpoint between the two shoulder joints toward the rear and trailing-arm side of the body increased the positive leading distance of the handle by generating the power of the legs and trunk simultaneously.
The purpose of the present study was to examine the influence of tendon elasticity, muscle strength and muscle activities on the amount of mechanical work enhancement associated with a counter movement. Twenty-one athletes performed a unilateral maximal jump using only the ankle joint with (CMJ) and without (no-CMJ) a counter movement on a sledge apparatus. Mechanical work done by the ankle joint was calculated from the ground reaction force and ankle joint kinematic parameters, and the difference between CMJ and no-CMJ conditions (ΔWork) was determined. During the exercise, electromyographic (EMG) activities were recorded from the triceps surae muscles. The maximal isometric plantar flexion torque and Achilles tendon stiffness were also determined using a torque meter and ultrasonogram. No significant correlation was found between ΔWork and either tendon stiffness or the maximal torque. In addition, neither the difference between CMJ and no-CMJ in iEMG nor mEMG was correlated with ΔWork. On the other hand, ΔWork was significantly correlated with the integrated EMG during the braking phase (r=0.52, p<0.05) and both the integrated (r=0.55, p<0.01) and mean (r=0.53, p<0.05) EMG during the push-off phase of CMJ. These results suggest that individual differences in ΔWork are influenced not by differences in the mechanical properties of the muscle-tendon unit, but by the individuality of muscle activities during CMJ.
In recent years, the reduced ability of infants to control their body movements has been studied. However, no appropriate exercise program based on the evaluation of physical control itself has yet been developed and implemented. Therefore, we have suggested that measurement and evaluation of the motor performance of infants should focus not only on their performance but also factors during the movement process itself. The aim of the present study was to acquire knowledge about an effective exercise program to promote the development of body control ability. For this purpose we used a task involving hopping on an elastic surface (the HES task) that requires higher body control ability, and examined the factors and movement characteristics related to task accomplishment. First, we evaluated the relationship between the HES task and other elements of physical strength (foot balance, standing broad jump, and side jump). Second, we studied the head position, tilt of the legs, direction of the toes, and line of vision at the time of landing during the HES task by using an easy method of observation evaluation, and assessed the influence of these factors on the task. The results of this study are summarized as follows: (1) The HES task was significantly correlated with the standing broad jump and side jump. (2) The time required to complete the HES task depended on a quick landing. In addition, head stability, tilt of the legs, and movement of the eyes before landing were found to be important factors influencing a quick landing. These results suggest that body control during rhythmical hopping on an elastic (unstable) surface can be assessed by studying the head position, line of vision, and tilt of the legs during the HES task.
The purpose of this study was to examine the influence of short-term affect resulting from a physical education class on long-term affect and self-efficacy for exercise. Thirty-seven male university students who attended a physical education class were recruited as participants. The class was conducted once a week for twelve weeks, and four evaluation scales were used: The Waseda Affect Scale of Exercise and Durable Activity (WASEDA), the Feeling Scale (FS), which is an affect scale for assessing the acute affects of exercise, the Japanese version of the Positive and Negative Affect Schedule (PANAS) to assess long-term affect, and the self-efficacy for exercise scale to assess the self-efficacy of maintaining exercise behavior. The participants rated the WASEDA and the FS at the end of each class session, and then we calculated the average score of each affect for these two scales. They responded to the PANAS and the self-efficacy for exercise scale at the end of the whole physical education program. It was found that Positive Affect as rated by the PANAS after the class was related to the average score for Positive Engagement. Furthermore, the average score for Positive Engagement was related to self-efficacy for exercise after the class. On the other hand, the average score for Negative Affect (WASEDA), Tranquility, and Pleasantness was not related to long-term affect or exercise self-efficacy after the class. In conclusion, the present study identified the importance of positive engagement in a physical education class. Future studies should explore the exercise prescription for obtaining activated and positive engagement along with acute exercise.
The purpose of this study was to investigate the similarities of upper torso rotation and pelvic rotation around the vertical axis of the global coordinate system with trunk rotation during throwing and striking movements. We enrolled twenty-three right-handed male college students, who performed baseball pitching and batting movements and the golf driver shot. During the throwing and striking movements, 3D coordinates of body landmarks were obtained using the VICON 612 system with 10 cameras operating at 120 frames per second. The ball speed during pitching and the head speed during batting and the driver shot were measured using a high-speed camera at 250 frames per second and analyzed using WINanalyze (2D motion analyzer). The angles of rotation of the upper torso and pelvis were calculated as the angles between the respective segment and the global x-axis. The trunk rotation angle was calculated as the angle between the upper torso segment and the pelvic segment. The sequential data for rotational movement variables were normalized from the onset of the minimum upper torso angle until release or impact. There were significant positive correlations between the ball speed during pitching, head speed during batting, and head speed during the driver shot (pitching vs. batting, r=0.627, p<0.01; pitching vs. driver shot, r=0.670, p<0.01; batting vs. driver shot, r=0.554, p<0.01). There were significant positive correlations between the two striking movements with regard to the maximum angular velocity of upper torso rotation (r=0.567, p<0.01) and pelvic rotation (r=0.523, p<0.05). The batting and driver shot showed similarity of trunk rotation and pelvic rotation in that the contribution of pelvic angular velocity to the maximum upper torso angular velocity was larger than the contribution of trunk rotational angular velocity to the maximum upper torso angular velocity. Upon trunk rotation, there were no significant positive correlations among the pitching, the batting, and the driver shot with regard to maximum angular velocity. These results indicate that the ball and head speeds are strongly related during pitching, batting, and the driver shot. The upper torso rotation and pelvic rotation around the vertical axis of the global coordinate system are related only during batting and the driver shot.
Although a change in running direction is one of the most important skills for ball game players, there is little information on the techniques involved, and the criteria used for technical evaluation. The purposes of this study were to develop indices for evaluating the techniques involved in changing the direction of running (i.e. cutting motion), and to compare the motions used by skilled and less-skilled groups to gain insight into the cutting motion technique. Twenty male university players of several ball games participated as subjects. They performed three kinds of 30-m zigzag runs with directional changes in angle of 30, 60 and 90 degrees, using the side-step and cross-step techniques. Their motions were videotaped with two digital video cameras operating at 60 Hz for three-dimensional motion analysis. The running time was measured by an electric timing device with photocell sensors. The velocity of the center of gravity (CG), angle of direction change, and angles of shank inward lean and thigh were calculated. We developed a cutting motion index that was calculated from the distance between the CG positions before and after cutting, the horizontal velocity of the CG at the beginning of cutting, and the elapsed time during cutting. The index gives a ratio of the time estimated from the horizontal velocity of the CG at the beginning of cutting relative to the actual elapsed time. The major results are summarized as follows: 1) For zigzag runs except for a 60-degree change in direction in the cross-step technique, there was no significant relationship between the cutting motion index and the angle of direction change. 2) In the side-step technique, the acceleration of the CG, the extension of the knee and hip joints, and the maximal forward lean angular velocity of the thigh in the second support phase were larger in the skilled group than in the less-skilled group. 3) In the cross-step technique, the deceleration of the CG and the flexion of the knee joint were smaller, but the acceleration of the CG and the maximal forward lean angular velocity of the thigh in the second support phase were larger in the skilled group than in the less-skilled group. These results indicate that the technique used to maintain running speed can be evaluated by the cutting motion index, and that the angle of direction change can be used as an index of direction change for the cutting motion. In the side- and cross-step techniques, a fast forward lean of the support thigh in the second support phase is likely to be an effective motion for maintaining the speed of the CG. In the side-step technique, extension of the knee joint in the support phase increases the forward lean angular velocity of the thigh. A fast forward lean of the support leg is effective in the cross-step technique.
The aim of the present study was to examine semantic generation related to experiences associated with sports activities, and to clarify the moments at which semantic generation occurs. Although Yano and Kubo did not discuss the issue of expanding experience, they acknowledge the possibility of semantic generation in dissolved experience, which is similar to expanding experience. Grupe perceived the achievement of voluntary and autotelic play following the rules of the game as the general semantic of sports, and mentioned several derived semantics, i.e. physical and self-personality experiences, health and well-being, excitement and tension, connections with others, involvement with nature, aesthetics and drama, and play-related motivation. Studies in this area have confirmed that semantic content other than play-related motivation is derived from either dissolved experience or expanding experience. Dissolved experience should therefore be interpreted as generation and expanding experience as semantic generation. Next, focusing on the expanding experience to which Yano and Kubo have not referred, a problem has arisen regarding the meaning of semantics and how to investigate the momentum of semantic generation. The results derived so far suggest that semantics refers to primary semantic actions, rather than content, and that in order to achieve semantic generation, recombination of already formed concepts is needed. In this regard, ”flesh” may be considered an opportunity for recombination, or a type of denial. With regard to situations in which semantic generation can be experienced, or more concretely, situations in which aspect modifications can be experienced, it can be considered that these represent a state of double bind as one form of communication, and the present study considers situations involving such experiences in sports. For example, when passing the ball in soccer or running a crucial leg of a long-distance race, athletes may experience an adverse situation and change their views and mind-set to overcome it. Such experiences will prompt a conversion of interpretation schema of the athlete him/herself.
The purposes of this study were to investigate 1) the effects of acute exercise on affect, 2) changes in self-efficacy resulting from acute exercise and the relationship between affect and self-efficacy, 3) correlation of factors in the Waseda Affect Scale of Exercise and Durable Activity (WASEDA: Arai et al., 2003) during acute exercise. Thirty-eight university and graduate students were recruited as participants in this study. The parameters measured were 1) exercise-specific affects (WASEDA), 2) pleasure-displeasure (Feeling Scale: Rejeski, 1985), 3) self-efficacy for acute exercise, and 4) Rating of Perceived Exertion (RPE: Onodera and Miyashita, 1976). This study employed a 2 (condition)×5 (time) format, within a participant factorial design, consisting of three sessions (a trial session, a cycling session, and a control condition). For the cycling session, the participants performed cycling at a RPE intensity of 13 (feeling “Somewhat hard”) for 20 minutes. Under the control condition, the participants read a book for 20 minutes. The participants then reported their preferred affect and pleasure experienced during cycling in comparison to the control condition. Not only was self-efficacy increased through the exercise task, but also positive affect during the exercise task was related to self-efficacy after exercise. Because correlations of WASEDA factors during exercise were not too high, it was considered that none of the factors in WASEDA were redundant. In conclusion, the present findings indicate that 1) the effects of acute exercise on affect are positive, 2) enhancement of positive affect during exercise is related to higher self-efficacy for acute exercise, and 3) the use of WASEDA is effective for multilateral investigation of affect during acute exercise.
The Korean government introduced the Traditional Martial Arts Promotion Law in 2008, which was the first governmental bill aimed at the preservation and promotion of Korean traditional martial arts. The law consists of 6 articles, including the definition of Korean traditional martial arts, the necessity of a master plan for their promotion, provision of support for traditional martial arts groups, and the fostering of leaders. This paper outlines the process of establishment of this law and attempts to clarify how Korean martial arts were conceptualized, authorized and invented as a Korean cultural tradition.
The essential element of ball games is a competition with a future unknown result (the objective of competition). In such a situation, the players engage in competition tasks to directly achieve their objective. This paper clarifies the relationship between the various activities of learners (extension of concept) and learned contents (intention of concept) through organization of tasks and the processes involved in task-solving. Any type of ball game has one of two distinct objectives: progression of the ball to an objective point, or progression of players to an objective point. Ball or player progression is accomplished either through conflicts between offense and defense or by the personal activities of an individual player. Considering these elements, the processes of task-solving can be classified into four types: “target-shooting”, “breakthrough”, “breakthrough+target-shooting”, and “breakthrough+base-advance”. Each type of task-solving represents a fundamental learning aspect of the ball game. Furthermore, based on the layered structure of the defensive threshold and the method selected for breaking through the structure, three phases of confrontation between offense and defense can be distinguished. Especially in the process of breakthrough task-solving, players select the specific application of ball manipulation (“pass” or “carry”) depending on the ratio between two antagonistic intentions: ball-possession and ball-progression. These findings provide a new perspective for instruction in ball games, which would enable learners to construct the processes as a meaningful experience, rather than merely reproducting solutions for the tasks of the competition.
When a unilateral transfemoral amputee performs sprinting, alternation between the sound limb and the prosthetic limb causes asymmetrical motion. One of the causes of the asymmetrical sprinting performance is that the knee joint of the prosthetic limb does not flex easily due to strong flexion resistance in order to prevent giving way during the landing by extension delay of the shank after flexion in the swing phase. This study examined whether the prosthetic limb performs the same motion as the sound limb working with the movements of the hip joint and other areas by setting the knee joint to allow easier flexion when relaxing the flexion-and-extension resistance of the knee joint in the swing phase. Moreover, when possible, we also examined whether this allows more rational motion than during sprinting when the flexion resistance of the knee joint is set strongly. The composition of the prosthetic limb used for the trial was an IRC (Ischial Ramal Containment) suction socket, high-activity hydraulic knee joint (model 3R55; Otto Bock, Duderstadt, Germany) in which the flexion-and-extension resistance was relaxed, in combination with an energy-storing prosthetic foot for running (model Sprinter; Otto Bock, Duderstadt, Germany). Sprinting was performed by a unilateral transfemoral amputee using this prosthetic limb after the subject had learned how to sprint while using it. Sprinting performance was filmed (30 fps) with a video tape recorder (DCR-PC101 NTSC, Sony Corporation, Tokyo, Japan), and we compared the motion of the prosthetic foot and the knee joint angle with the motion of the sound limb. Moreover, the motion was also compared with that during sprinting when the flexion-and-extension resistance of the knee joint was set strongly. As a result of the relaxed setting of the prosthetic knee joint, it was shown that the prosthetic limb performed the same motion as a sound limb without giving way at landing by extension delay of the shank of the prosthetic limb during the swing phase. Moreover, it was shown that this setting facilitates more rational motion than that during sprinting with a stronger setting for the flexion resistance of the knee joint.
The Relapse Prevention Model (RPM) has provided a framework for successful long-term maintenance of some types of health behavior. The purpose of this study was to identify high-risk situations for inducing exercise slip and lapse, which may lead to real relapse, and to clarify the coping strategies in this regard for Japanese regular exercisers, from the viewpoint of the RPM. We examined 677 regular exercisers by obtaining open-ended responses about 1) their typical high-risk situations as immediate determinants interfering with their planned exercise, 2) their coping responses to those situations, and 3) subsequent patterns of exercise outcome. High-risk situations included fatigue, bad weather, bad conditioning or injury, work or academic obligation, troubles in personal life, interpersonal relationships, and getting into a groove, although the frequency orders differed according to gender. Females were more aware that interpersonal relationships were associated with a higher incidence of exercise slip and lapse than did males, whereas males identified fatigue as the highest risk. Positive coping strategies as problem solving and behavior strategies as execution of routine work were most commonly employed, and were associated with positive exercise outcome for both females and males. On the other hand, the usage of negative coping strategies tended to lead to slip and lapse. These results suggest that adoption of coping strategies regarding high-risk situations is associated with exercise outcome, although the effects differ between males and females. These data demonstrate the importance of coping ability or strategy for exercise and suggest that slip and lapse may result from ineffective coping with high-risk situations. These findings confirm and extend previous work on the application of the RPM for examining exercise slip and lapse. Measurement issues and knowledge derived from this study are discussed in relation to future application to real practice.
PE teachers usually take actions that are based on prior mental reflection. In order to do so, they must possess creativity to cope with any situation and also implement effective techniques in a timely manner. The present study was performed to evaluate these capacities in PE teachers from the viewpoint of self-recognition. The effectiveness of the method used for capacity evaluation was also evaluated. For this evaluation, teachers were requested to state what they recognized during teaching employing the following three scenarios: 1) Teachers reproduced their feelings of recognition while watching a VTR of the whole space in a classroom; 2) Teachers reproduced their feelings of recognition while watching a VTR representing the teacher's view of the classroom; 3) Teachers simply stated what they recognized while actually teaching. It was found that scenario 3 was the best way of grasping a teacher's recognition, and was also effective for clearly demonstrating feedback/feed forward elements.
The 2007 statistics from 11 prefectural police departments in central Honshu (the largest island in Japan) regarding incidents in mountain areas were subjected to detailed analysis to assess the risk levels associated with mountain activities. These statistics were also compared with published statistics on mountain incidents that form the current basis for analysis of mountain incidents. The results of this analysis were: 1) The highest incidence rate is in the 50-69 age group for men, and the 40-59 age group for women. 2) A high percentage of incidents among people over the age of 40 and people getting lost reflected characteristic of incidents among people who were picking wild vegetables. 3) Incidents that were not officially classified as “getting lost”, but began when someone got lost their way, had a high risk of fatal injury. 4) Incidents that involved people getting lost were due not only to poor navigation skills but also to poor planning, a lack of general knowledge about mountain areas, and low basic skill levels. The importance of detailed analysis of mountain incidents for promotion of mountain safety is discussed.
This study investigated the cross-sectional area of the gluteus maximus muscle in high school athletes with reference to sex- and sport-related differences. The subjects were 269 male and female athletes (age 17.2±0.7 yr) majoring in 12 events: sprinting, long-distance, throwing events, volleyball, badminton, boating, canoeing, sailing, soccer, basketball, wrestling and judo. Thirty-six untrained high-school students also participated as controls. The muscle cross-sectional area (CSA) was determined from an axial magnetic resonance image using a slice level through the greater trochanter. Fat-free mass (FFM) was also measured by air-plethysmography, and the relationship between CSA and FFM was analyzed. The CSA and FFM showed a high correlation (r=0.80 for males and 0.71 for females) and there was no gender difference in the regression equation (CSA=3.92*FFM0.83 for the pooled data). The absolute CSA was larger in males than in females. The largest CSA was found in judo and throwing-event athletes of both genders, and the smallest in canoeing and long-distance athletes, whose CSA was comparable to that of the controls. However, when the CSA was divided according to FFM0.83 in order to control for body-size difference in sex and sports events, there was no significant difference in the value between genders. Moreover, although the body-size controlled value was the largest in badminton and sprint athletes of both genders, no significant event-related differences were found for males, and only canoeists showed a value that was less than that for badminton and sprint athletes among females. In conclusion, the development of the gluteus maximus appears to show a sport-specific difference among high school athletes; however, compared with thigh muscle groups suggested in previous studies, no sports-specific tendency was apparent when FFM was controlled for.
To investigate the structure of daily living stressors and mental health status, we distributed a self-report questionnaire to a sample of 279 undergraduates of a university in the Kyushu area. Evaluable data were obtained from 231 undergraduates, yielding an effective response rate of 82.8%. The score for the Center for Epidemiologic Study Depression Scale (CES-D) in the present sample was 19.07 (SD=9.01), which was higher than results obtained in previous studies. Data for daily living stressor items were subjected to factor analysis, followed by varimax rotation. The factor analysis yielded six factors: task for study, spiritless daily living, part-time employment, traffic accidents, business and constraints of daily living, and laziness with study. Chronbach reliability coefficients indicated that our original stressor scale had medium or sufficient internal consistency. Comprehensively, it was revealed that the present daily living stressors had high commonality across the CES-D scale/subscale. In particular, the task for study and spiritless daily living were correlated with the CES-D score, showing a higher correlation than other daily living factors. Therefore these two stressors may be suitable for identification of depressive symptoms. On the other hand, although the response for traffic accidents was low, it was considered that this type of daily living stressor might have a partial influence on depressive symptoms among university undergraduates. Our findings indicated that daily living stressors were detectable from descriptive data based on the demographic characteristics of the present cohort. Accordingly, our results suggest that the present set of stressors were meaningfully subjective for undergraduates in the department of education and should be taken into account to fully understand the actual mental status of undergraduates and for formulating the ideal situation in a university for the mental health of the students.
The purpose of this study was to examine the physical activity of school children during camping in a mountain environment. The subjects were 20 children (1st-3rd grade) who participated in the camp, which was carried out in a typical mountain village area of Tohoku district during five days in the summer vacation. Physical activity (steps and times engaged in light to moderate and vigorous intensities of physical activity) was measured by uniaxial accelerometer (LifecorderEX, Suzuken Co., Ltd.). The data were compared with those of previous studies on the physical activity of children during weekdays and weekends during school term using the same method. The number of steps during camp activity were similar to those on weekdays during school term, and greater than during holidays. Moreover, the times engaged in light to moderate activity such as standing activity, and fast-paced walking (2.0-6.0 Mets) during the camp were greater than those on weekdays at school and during holidays. These results suggest that children's experience of activities in a natural environment through the camp and interest in natural environments promote voluntary physical activity by children. Therefore, it is possible that such camp activity plays an important role in promoting the voluntary physical activity of children during the long or short vacation.