International Journal of Sport and Health Science
Online ISSN : 1880-4012
Print ISSN : 1348-1509
ISSN-L : 1348-1509
Volume 5
Showing 1-17 articles out of 17 articles from the selected issue
  • Ian Culpan, Judy Bruce
    Type: Paper
    Subject area: Pedagogy
    2007 Volume 5 Pages 1-11
    Published: 2007
    Released: November 16, 2007
    JOURNALS FREE ACCESS
    The need for critical pedagogy to be used in physical education has created significant discussion and debate over the last decade. While many scholars advocate for critical pedagogy, there is concern that there is a lack of practical applications. In New Zealand, recent neo-liberal economic imperatives have necessitated the complete revision of the school curriculum. The curriculum revision was designed to ensure that New Zealand was economically competitive on the world stage. In revising the physical education curriculum, the curriculum writers of this document took a socio-critical stance and have produced a document, mandated by the state that advocates for critical pedagogy. This paper explores critical pedagogy within New Zealand's physical education context including the curriculum and discusses how physical education in New Zealand is attempting to address the challenge of engaging in critical pedagogical praxis.
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  • Takahiro Nakano, Takahiko Nishijima, Takeshi Suzuki
    Type: Paper
    Subject area: Epidemiology
    2007 Volume 5 Pages 12-20
    Published: 2007
    Released: November 16, 2007
    JOURNALS FREE ACCESS
    The purposes of this study were to extract the lifestyle guidelines for optimum conditions using the decision tree analysis and to show the effectiveness of the decision tree analysis on routine athletic conditioning data. The subjects were five athletes, three males and two females who were measured over a total period of 1323 days. Three factors concerning the athletes' perceived condition and nine items concerning their basic lifestyle were observed daily using a “Quality Control (QC) Sheet”. Two or more methods were tested to treat the missing value, and the method that most maintained the distribution characteristic (mean and standard deviation) of data was applied to treat missing value. Data was standardized to each subject because a significant difference was admitted in the data of each item among subjects and the data were enabled to treat on same dimension. Decision tree analysis was applied to extract the lifestyle rule for optimum conditions. Three items concerning perceived condition were dependent variables and nine items concerning basic lifestyle were independent variables. Valid classification decision trees were made, and the lifestyle guidelines for optimum condition were drawn up. For each dependent variable, the first split variable was the time subjects got up and the second split variable was the length of sleeping hours. The effectiveness of decision tree analysis for athlete's data concerning lifestyle was validated since lifestyle guidelines for optimum conditions were extracted.
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  • Ryosuke Tsuda, Toru Shinozaki, Kunio Goto, Kaoru Takamatsu
    Type: Paper
    Subject area: Pedagogy
    2007 Volume 5 Pages 21-31
    Published: 2007
    Released: November 16, 2007
    JOURNALS FREE ACCESS
    This study focused on mini games, commonly used as teaching material in soccer classes, and examined the effects of rule changes on load characteristics from the viewpoint of the improvement in physical fitness. Eighteen male junior high school students participated in the present study. They played in three types of mini 4 vs 4 games : a free game, a pass game and a man to man game. The number of ball contacts, the ratio of appearance time of each movement speed (0-1, 1-2, 2-3, 3-4, 4-5, 5-6m / sec), the total movement distance, heart rate and RPE during the game were measured. Questionnaires were conducted after all games. Skill tests (pass and dribble tests) and physical fitness tests (50m sprint, 250m sprint with a change of direction (25m × 10 sets with 30 sec rest), and 20m shuttle run) were also performed. The main results were as follows : 1) The number of ball contacts during the game was significantly greater in the pass than in the man to man games. 2) The ratio of movement at lower speeds (1∼2m / sec) was significantly greater in the free than in the man to man games, whereas those at moderate and higher speeds (3∼4, 4∼5 and 5∼6 m / sec) were significantly greater in the man to man than in the free games. 3) Total movement distance was significantly greater in the man to man than in the free games. However, there was no significant difference in heart rate and RPE among the three games. 4) The results of questionnaire showed partial significant differences in technique and fitness aspects among the three games, whereas no significant difference was observed in the psychological aspect. 5) In the free and man to man games, a significant correlation was observed between the number of ball contacts during the game and the results of the pass test, whereas no significant difference was observed in the pass game. These results suggest that the load characteristics of the soccer game from the viewpoint of improvement in physical fitness differ greatly when the rules of the mini games are changed. In addition, the pass game might be available to provide increased opportunity for unskilled children to participate in the games.
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  • Takeshi Nishijima, Hirokazu Tashiro, Morimasa Kato, Tsuyoshi Saito, Ta ...
    Type: Paper
    Subject area: Physiology
    2007 Volume 5 Pages 32-41
    Published: 2007
    Released: November 16, 2007
    JOURNALS FREE ACCESS
    Ingestion of glycerol with a large volume of fluid causes hyperhydration, which has been shown to increase thermoregulatory capacity and improve exercise performance under hot conditions, but in some cases causes nausea and headaches. However, it is still uncertain what kind of hydration regimen would be effective in producing a greater hyperhydration state and whether glycerol hydration would affect mood. This study compared the hyperhydration effectiveness of different hydration regimens, then examined whether glycerol hyperhydration prior to exercise alleviates exercise-induced dehydration, improves exercise performance under hot conditions, and affects mood while hydrated. Both the Bolus-G regimen: ingesting a relatively high concentration of glycerol fluid at the beginning of the hydration phase, and the G regimen: ingesting a low concentration of glycerol fluid through hydration phase, caused significant increase in body weight and decrease total urine volume, but there was no significant differences between two regimens. Ninety minutes after glycerol or placebo hydration by the Bolus-G regimen, six healthy well-trained volunteers performed a 70-min cycling test. The decrease of body weight after exercise versus pre-hydration was significantly smaller in the glycerol trial (1.4% of body weight) than in the placebo trial (2.5%). There were no significant differences in exercise performance and mood measured by a two-dimensional mood scale during the hydration phase. These results suggest that hyperhydration by glycerol alleviates exercise-induced dehydration during exercise in a hot environment but with no changes in exercise performance and mood.
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  • Ryosuke Tsuda, Toru Shinozaki, Kunio Goto, Kaoru Takamatsu
    Type: Paper
    Subject area: Pedagogy
    2007 Volume 5 Pages 42-53
    Published: 2007
    Released: November 16, 2007
    JOURNALS FREE ACCESS
    This study focused on mini games in soccer, a game generally used as teaching material in PE classes, and examined the effect of differences in the size of the court and the number of the players on load characteristics from the viewpoint of improvement in physical fitness. Twenty male junior high school students participated in the present study. They played four types of games with changing the size of the court and the number of the players: Game A (court size: 30m × 20m, 5 players per team, court area per player: 120m2); Game B (court size: 45m × 30m, 5 players per team, court area per player: 270m2); Game C (court size: 45m × 30m, 10 players per team, court area per player: 135m2); Game D (court size: 60m × 40m, 10 players per team, court area per player: 240m2). The number of ball contacts, the ratio of appearance time of each movement speed and the total movement distance during the game were measured. Questionnaires about the game were conducted after all games. Skill test (pass and dribble tests) and Physical fitness test (50m sprint and 20m shuttle run) were also performed. In analysis of data, eight students among twenty were used. The main results were as follows: 1) The number of ball contacts was greater in small-group games A and B than in large-group games C and D. Among them, there were significant differences in Game A and both Games C and D. 2) The ratio of the appearance time of each movement speed showed no significant difference among the four games at any speed. However, moderate speeds (3-4m / sec) tended to be greater in Game B, in which the number of the players was smaller and the court area was larger (p =0.08), and higher speeds (4-5m and 5-6m / sec) tended to be greater in Games B and D, in which the court area per player was larger. 3) Questionnaire scores were greater in the psychology component (4.0 to 5.0 points) and techniques component (coordination) (4.0 to 4.8 points) than in the physical fitness component (2.9 to 4.1 points), however, no significant difference was revealed among the four games in any questions on any aspect. In the psychology component question which asked about interest, small-group games A and B tended to reveal greater interest than large-group games C and D (p =0.08). 4) In Games A and C, in which the court area per player was smaller, there was a significantly positive correlation between the number of ball contacts and the results of the pass test, while there was a significantly negative correlation between the number of ball contacts and the results of the dribble test. 5) In Games C and D, in which the number of the players was larger, there was a significantly positive correlation between the total movement distance and the results of 20m shuttle run in the physical fitness test. The results suggest that small-group games might improve technique (coordination) in addition to evoking students' volition for learning, and that games in which the court area per player is larger might be available for improvement in their anaerobic power. Additionally, the results suggest that for games in which the court area per player is smaller, differences in basic techniques might affect the number of ball contacts during a game, while for games in which the number of players is larger, differences in aerobic capacity might affect the total movement distance during a game.
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  • Tatsuaki Ikeda, Kaoru Takamatsu
    Type: Paper
    Subject area: Coaching and Training
    2007 Volume 5 Pages 54-62
    Published: 2007
    Released: November 16, 2007
    JOURNALS FREE ACCESS
    The purpose of this study was to investigate muscle oxygenation during intense dynamic knee extension exercise, after a classification into four groups based on the relative merit of one repetition maximum (1RM) and the total number of repetitions loaded at 90%, 70% and 50% of 1RM (Ntotal). Thirty six male university undergraduate and graduate students with experience in various sports participated in the study. Subjects performed knee extension exercise at 1RM and a number of repetitions loaded at 90%, 70% and 50% of 1RM. Subjects were divided into four groups based on the results of 1RM and Ntotal (SN group : 1RM-high / Ntotal-high, Sn group : 1RM-high / Ntotal-low, sN group : 1RM-low / Ntotal-high, sn group : 1RM-low / Ntotal-low). Muscle oxygenation on the vastus lateralis muscle was measured during the repetition exercises. The minimum value and rate of decrease at onset of repetition exercise (4-9 seconds after the start of exercise) were calculated to estimate muscle oxygenation. The major findings were: (1) The relative merit of 1RM and number of repetitions at relative intensity affected the muscle oxygenation during repetition exercise. (2) A significant negative correlation between Ntotal and rate of decrease of muscle oxygenation was observed with loads at 70% and 50% 1RM, but not at 90% 1RM. These results suggest that it is important to focus on the improvement of aerobic capacityin resistance training to increase the number of repetitions at relative intensity.
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  • Yoichi Ohta, Norihiro Shima, Kyonosuke Yabe
    Type: Paper
    Subject area: Physiology
    2007 Volume 5 Pages 63-70
    Published: 2007
    Released: November 16, 2007
    JOURNALS FREE ACCESS
    This study examined changes in mechanical properties of medial gastrocnemius muscle (MG) and soleus muscle (SOL) at different contraction intensities using superimposed mechanomyogram (MMG) signals. The subjects were measured for the superimposed twitch amplitude and peak acceleration of the twitch torque development (d2T /dt2) from electrical stimulation of the posterior tibial nerve during isometric plantar flexions at 20%, 40%, 60%, 80%, and 100% of maximal voluntary contraction (MVC). In addition, the superimposed MMG amplitude was recorded from MG and SOL. The superimposed twitch amplitude, d2T /dt2 and superimposed MMG amplitude of MG and SOL decreased with increasing %MVC. With increasing %MVC, changes in the pattern of superimposed MMG of the MG were similar to the changes in the pattern of d2T /dt2. There were significant relationships between the superimposed twitch amplitude and the superimposed MMG amplitude of MG and SOL, and the d2T /dt2 and superimposed MMG amplitude of MG and SOL. The normalized superimposed MMG amplitude of the MG at 20% and 40% of MVC is significantly higher than that of SOL. These results suggest that superimposed MMG signals recorded from synergistic muscle (MG and SOL) reflects individual mechanical activation levels at lower contraction intensity.
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  • Heung-Youl Kim, Shinji Sakurai, Jae-Han Ahn
    Type: Paper
    Subject area: Biomechanics
    2007 Volume 5 Pages 71-82
    Published: 2007
    Released: November 16, 2007
    JOURNALS FREE ACCESS
    The purpose of this study was to investigate the effect of errors in the center of pressure (CoP) locations on three-dimensional (3D) lower limb joint moments during the stance phase of gait. Kinematic and kinetic data were collected from walking trials of one healthy male subject (age: 22yr, height: 181cm, body mass: 80kg). Changes of 3D joint moment were calculated using inverse dynamics with 3D video analysis and ground reaction force (GRF) measurement. Thereafter, the location of the CoP was shifted toward the antero-posterior/medio-lateral direction by ±10mm, ±20mm and ±30mm, respectively, and 3D joint moments were recalculated with the shifted CoP data. As a result of the simulated shift of the CoP in the antero-posterior direction, changes of magnitude in the ankle (dorsiflexion-plantarflexion), knee (flexion-extension), and hip joint moments (flexion-extension) were observed, while the moment patterns did not change. Simulated CoP shift in the medio-lateral direction altered the magnitude of the hip joint moment (abduction-adduction, internal-external rotation). Moreover it greatly affected the change of the inversion-eversion ankle joint moment. A shift of ±10mm of CoP in the medio-lateral direction reversed joint moment pattern of ankle joint inversion-eversion. The joint moment magnitudes and patterns were more sensitive to errors in the medio-lateral direction than in the antero-posterior direction, largely due to differences in the moment arm length and the direction of the GRF. This clearly illustrates the need to accurately determine CoP position in the calculation of lower limb joint kinetics.
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  • Tamotsu Nishida
    Type: Paper
    Subject area: Psychology
    2007 Volume 5 Pages 83-97
    Published: 2007
    Released: November 16, 2007
    JOURNALS FREE ACCESS
    The present study was conducted to develop a Diagnosis of Learning Motivation in Physical Education Test (DLMPET), which measures learning motivation in physical education (PE) multilaterally and comprehensively, and to examine its applicability in educational settings. The DLMPET consists of the following subscales: 1) learning motivation in PE, 2) types of learning motivation in PE, 3) supporting factors for learning motivation in PE, 4) preferences in learning behavior, 5) interest in subjects and activities, and 6) PE class enjoyment. Results demonstrated adequate levels of validity and reliability for three of these subscales: learning motivation in PE, supporting factors for learning motivation in PE, and preferences in learning behavior. Five PE teachers who applied the DLMPET in their PE classes reported that the DLMPET was helpful in obtaining guidance to enhance children's learning motivation in PE settings. Based on these findings, it was concluded that the DLMPET was significantly useful to aid research and practice in educational settings.
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  • Akinori Nagano, Shinsuke Yoshioka, Taku Komura, Senshi Fukashiro
    Type: Brief Paper
    Subject area: Biomechanics
    2007 Volume 5 Pages 98-104
    Published: 2007
    Released: November 16, 2007
    JOURNALS FREE ACCESS
    The purpose of this study was to examine which of the following exhibited greater advantageous in achieving greater mechanical outputs, on the condition that muscle mass (thus the muscle volume) is identical: (1) to have a greater fascicle length, or (2) to have a greater physiological cross-sectional area (PCSA). (1) Corresponds to a thin and long muscle, whereas (2) corresponds to a thick and short muscle. Three simulation models of the human m. soleus in the region of the ankle joint were constructed. (A) The default model muscle parameter values were derived from the literature. (B) The optimal length of the contractile element (CE) was changed to 1.1 times and the maximal isometric force of the CE was changed to 1/1.1 times the original values. (C) The optimal length of the CE was changed to 1/1.1 times and the maximal isometric force of the CE was changed to 1.1 times the original values. The total muscle volume was unchanged through these modifications. Maximal-effort isokinetic plantarflexion/dorsiflexion activities were simulated at a variety of angular velocities. In concentric actions excluding those at very slow angular velocities, greater mechanical outputs were obtained with model (B). During eccentric actions, the mechanical output was consistently greater with model (C). The findings of this study raise suggestions related to assessing the aptness of individuals for athletic activities in which the competitors are classified by their body mass (such as weight lifting and judo). Results suggest that it is more advantageous to have a greater fascicle length (tall-and-slender physique) for concentric activities, whereas it is more advantageous to have a greater PCSA (short-and-thick physique) for eccentric activities.
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  • Yuki Hikihara, Koji Kanzaki, Shinichi Saitoh, Yutaka Yoshitake, Kaoru ...
    Type: Paper
    Subject area: Growth and Development
    2007 Volume 5 Pages 105-115
    Published: 2007
    Released: November 16, 2007
    JOURNALS FREE ACCESS
    It has been reported that the physical fitness of adolescents has been decreasing gradually over the past twenty years in Japan. The reasons for this decrement were a decrease in physical activity and an increase in the prevalence of obesity. However, there is no clear evidence on the relationships between physical activity and physical fitness or body composition for adolescents. The purpose of this study was to measure the total energy expenditure (TEE), physical activity level (PAL) and times spent in light, moderate and vigorous physical activity and to ascertain relationships between physical activity and physical fitness, and body composition for adolescents. Twenty four male adolescents (age: 17.3±1.3) volunteered for participation. Subjects assigned as trained adolescents group (n=16) and untrained group (n=8). TEE was measured by doubly labeled water method and times spent in physical activity were assessed by accelerometer method. VO2max was indirectly measured by breath-by-breath method with stepwise incremental cycle ergometer exercise test. Measurement of physical fitness tests was conducted according to the Ministry of Education, Culture, Sports, Science and Technology. TEE and PAL were significantly higher in trained adolescents (4813±439 kcal/day and 2.64±0.14) than untrained (2859±147 kcal/day and 1.84±0.16), respectively. Times spent in light, moderate and vigorous activities measured from accelerometer were significantly higher in trained adolescents than untrained, while times in sedentary activity were significantly higher in untrained adolescents than trained. PAL and times spent in physical activity (light, moderate, vigorous) were significantly correlated with physical fitness (Vo2max, sit-ups and sitting trunk flexion). Additionally, times spent in moderate related to 20-meter shuttle run. However, PAL and times spent in physical activity were not significantly related to %body fat. These results indicated that daily sport activity results in significant difference of activity energy expenditure between trained and untrained adolescents, and that increase in PAL and times spent in physical activity while engaging in daily sport activity would contribute to improvement of health-related fitness in adolescents.
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  • Masashi Watanabe, Masaru Kaga, Mutsumi Matsueda, Kayo Takahashi
    Type: Materials
    Subject area: Growth and Development
    2007 Volume 5 Pages 116-121
    Published: 2007
    Released: November 16, 2007
    JOURNALS FREE ACCESS
    The purpose of this study was to investigate the effect of sports activity on tibial bone strength in junior high school students. Tibial bone strength was evaluated by the speed of sound of tibia (t-SOS) using the Sound Scan 2000®. Thirty Male athletes, who participated in sports activities approximately 18 hours/week, were enrolled in this study. They were compared with 45 sedentary boys. t-SOS in athletes (3707±67m/sec) was significantly lower than that in sedentary boys (3779±114m/sec). Length of tibia in athletes (40.2±2.1cm) was significantly longer than that in sedentary boys (38.5±2.3cm). The value of t-SOS demonstrated a positive correlation with calcium intake from dairy products in athletes. These data suggest that sports activity and physique may affect tibial bone strength, and calcium intake may help to enhance tibial bone strength.
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  • Nobuyuki Miyatake, Motohiko Miyachi, Hidetaka Nishikawa, Takeshi Saito ...
    Type: Brief Paper
    Subject area: Aging and Health Promotion
    2007 Volume 5 Pages 122-124
    Published: 2007
    Released: November 16, 2007
    JOURNALS FREE ACCESS
    We investigated the relation between metabolic syndrome and whole body reaction time. We used data for 169 men with metabolic syndrome and 398 men without. Metabolic syndrome was defined by a new criteria developed in Japan. Whole body reaction time was also measured by THP-15 (Sakai, Tokyo, Japan). Whole body reaction time in men with metabolic syndrome was significantly longer than without the syndrome. In addition, the clinical impact of dyslipidemia and body mass index (BMI) was also noted. Longer whole body reaction time was noted in Japanese men with metabolic syndrome.
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  • Joon Ho Kang, Young Han Lee, Kwon Sihyeong
    Type: Paper
    Subject area: Management
    2007 Volume 5 Pages 125-134
    Published: 2007
    Released: October 11, 2008
    JOURNALS FREE ACCESS
    The purpose of this study is to evaluate management efficiency of professional teams in the Korean Baseball Organization by using Data Envelope Analysis (DEA). The professional baseball teams in Korea are in urgent need of efficient management as no teams are making profits and their financial deficits are growing. DEA is a technique to measure relative efficiency when coping with multiple inputs and multiple outputs. We implemented total player salary as input item and winning percent and total fan attendance as output item to evaluate 8 teams' management efficiency for the 2004 season. The analysis identified teams operating relatively efficient and teams that are not efficient. The result revealed that a team's efficiency score is not necessarily correlated to the final standings in the league. Rather, teams relatively mediocre sized outperformed the teams well-known for its financial abundance.
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  • Akira Nakagawa, Kohei Hirose
    Type: Paper
    Subject area: Coaching and Training
    2007 Volume 5 Pages 135-146
    Published: 2007
    Released: October 11, 2008
    JOURNALS FREE ACCESS
    The objective of this research is to clarify the factors to heighten success of ball acquisition in kick-off and 50m restart kick (KO) play from the view point of the kicking side. For that purpose, the process of ball acquisition of the kicking side was divided into three play elements: the kick, the contest for the ball, and the prompt ruck/maul formation after KO. A total of 448 KO plays in 43 world class matches were taken as samples and correlation between performance in each play element and ball acquisition rate of the kicking side was quantitatively analyzed. It can be concluded from the results of analysis as follows: 1) In order to increase the success rate of ball acquisition in KO play with respect to the kicking side, an important factor is for the kicking side to take some action against the ball earlier than the opponent at an aerial contest for the ball. 2) In order to realize it, an important factor is to create situations where the receiving side cannot employ the lifting play. It is also implied that in field practice, an effective way to improve the performances in KO play is to devise tactics and to have players achieve a mastery of techniques to realize the factors to heighten success of ball acquisition in KO play which have been made clear in this research.
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  • Zhen-Bo Cao, Akira Maeda, Norihiro Shima, Hiroshi Kurata, Hidetsugu Ni ...
    Type: Paper
    Subject area: Aging and Health Promotion
    2007 Volume 5 Pages 147-156
    Published: 2007
    Released: October 11, 2008
    JOURNALS FREE ACCESS
    This 1-year intervention study was designed to examine the effects of exercise and nutritional intervention on the improvement of physical factors associated with fracture risk in middle-aged and older women. One hundred twenty-six women aged 55-75 years were divided into one of 3 groups: an exercise group, an exercise and nutrition group, and a control group. Nutritional intervention was designed to encourage women to obtain sufficient daily protein (65g or over) and calcium intake (600mg or over). The setting was center-based and home-based exercise. Measurements were bone stiffness, one-leg stance, whole body reaction time, grip strength, 10m obstacle walk and 30-second chair stand. Results show that exercise intervention can significantly improve physical ability in older women with regard to one-leg stance, whole body reaction time, 10m obstacle walk and 30-second chair stand, suggesting that older women are able to ameliorate fall risk factors by exercise intervention. The exercise and nutrition group had success in modifying bone loss when compared with the exercise group, suggesting that multimodal intervention that includes exercise and nutrition targeted at correcting bone loss should be recommended. The results suggest that exercise and nutritional intervention may be an effective approach to fracture prevention in middle-aged and older women.
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  • Satoru Tanabe, Akira Ito
    Type: Materials
    Subject area: Biomechanics
    2007 Volume 5 Pages 157-167
    Published: 2007
    Released: October 11, 2008
    JOURNALS FREE ACCESS
    The purposes of the present study were to examine the distortions of three-dimensional kinematic data using existing three extrapolation methods and to determine the most effective extrapolation method for removing the influence of the collision between the racket and the ball during a flat power serve in tennis. For a flat power serve, it is natural that the velocity of the racket head toward the net would be maximal at impact, i.e., the acceleration would be zero. The present study shows that the criterion acceleration data toward the net was approximately zero. Since REF and LEX have characteristics that produce zero acceleration at impact, the differentiated data toward the net in REF and LEX were similar to the criterion data in analysis at 1000 Hz. However, in analysis at a lower sampling time, at which the practical analysis of tennis movement was commonly analyzed, LEX yielded high acceleration from just before impact, and the difference between the criterion velocity data and the velocity in LEX at impact became large in proportion to the shortening of sampling time. In contrast, REF invariably produced the zero acceleration at impact, and the velocity in REF at impact was similar to the criterion velocity data for each sampling time. Thus, in the practical analysis of the tennis serve, REF is the most suitable method for correcting the distortion by the collision between racket and ball for the axis toward the net, where the acceleration would be zero at ball impact.
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