Purpose The purpose of this study was to investigate the differences in physique and physical fitness according to maturity between primary and middle school baseball players. Methods Participants were 112 elite youth baseball players (49 primary school; 63 middle school). Skeletal age estimated maturity. Physique (height, arm span, thigh volume), body composition (weight, muscle mass and body fat), physical fitness (strength, power, agility, flexibility, coordination, anaerobic power and aerobic power) were measured. An independent sample t-test was used to conduct verify the difference between physique and physical fitness according to maturity. Results The results of analyzing physical and physical fitness according to maturity showed that there was a significant difference (p<.05) between the early maturation group and on-time group in primary school baseball players, body fat percentage, muscle mass percentage, sit-up, anaerobic power and reaction time. There was a significant difference between the early maturation group and the on-time group in the middle school baseball players, weight (p<.05), thigh volume (p<.05), fat mass (p<.05), muscle strength (p<.01), power (p<.05) and coordination (p<.05). Conclusions In conclusion, the maturity of a growing baseball player may be influenced by the performance, so maturity status should be considered when judging the performance of a growing baseball player, especially a middle school baseball player.
Purpose The purpose of this study is to explore the trend of K league exodus and its factors. Methods Qualitative case study was conducted by selecting 9 footballers and 7 their agents as the participants who have migrated from South Korea to China and the Middle East. Results The factors of migration were categorized as three push and pull factors such as economy (individual income and club's profit), policy (employment for foreign and military service) and environment (markets in home and abroad). To understand sport migration in the economic factor, there should be the environmental condition (overseas market) to pay high salaries and transfer fee to individuals and their clubs, and at the same time, the domestic market should be relatively poor environment. In addition, this study overcame limitations of economic and environmental factors by classifying Asian quota system and military service into political factor, and found the specificity (local context) of K league. Conclusions In conclusion, this study can be regarded as the first empirical work on sport labor migration in Korea and valuable as basic data of follow-up studies.
[Purpose] This study aimed to investigate the structural relationships among event quality, spectators‘ destination image, country image, and behavioral intention in the international cycle competition, Tour de Korea 2017. [Methods] The questionnaire was structured in four dimensions: event quality (three sub-dimensions and twelve items), destination image (three items), country image (three items), and behavioral intention (four items). A total of 292 spectators from six hosting cities (Yeosu, Gunsan, Muju, Yeongju, Cheongju, and Seoul) during the event participated in this study. Factor analysis, reliability, validity, correlation analysis, and structural equation modeling analysis were conducted utilizing SPSS 21.0 and AMOS 21.0. [Results] This study indicated that event quality in an international sporting event was found to be the significant factor of spectators’ destination image and country image, which, in turn, significantly influenced the spectators’ intention to revisit to the place of the event and/or the event itself. [Conclusions] The findings of the present study contribute to theoretical understandings of event quality that predicts spectators’ behavioral intention and destination image in a global sporting event. Practically, this study also provides some important suggestions for practitioners who plan marketing strategies for international sporting events.
Purpose The purpose of this study was to investigate the effects of a functional fatigue protocol on lower extremity dynamic and static postural control. Methods A total of 20 physically active collegiate students participated in this study (ten males, ten females; age 22.5±2.7 years; mass 67.0±13.0 kg; height 168.0±8.9 cm). A unilateral stance with eyes closed for 10 seconds was performed to test static postural control using a balance force plate and single-leg drop landing on 30cm box was performed as a dynamic postural control test and captured using VICON motion analysis system. Results The results of this study showed an average heart rate of 176.3 beats/minute, an 18 rating on the perceived exertion scale, significant differences in blood lactate, and a static postural control deficit after fatigue as compared with before fatigue(p<.05). Dynamic postural control after fatigue changed landing strategy in the form of stiff landing. Knee flexion was decreased at initial contact and at peak vertical ground reaction force, also, both decreased valgus and internal rotation of knee joint. Conclusions This protocol may use for enhancing fatigue-endurance training as well as for inducing fatigue. Further, to ascertain a landing strategy, it is recommended to increase landing height to clearly observe changes in landing strategy.
Purpose Common content knowledge(CCK) is composed of rules, techniques, and tactics. Such knowledge is a requirement for effective teaching of physical education (PE). There are, however, few validated tests of CCK. Thus, the purpose of this study was to develop a CCK test of soccer and evaluate the validity and reliability of the test using Rasch modeling (Rasch, 1980). Methods We developed thirty item common content knowledge test for soccer. Then, we used Rasch modeling to evaluate the validity and reliability of a test of soccer. Pre-service teachers (N=92) majoring in physical education and non-PE major (N=111) participated in this study. Results Thirty questions demonstrated good item-model fit. Moderately high internal consistency for person-ability and high internal consistency for item-difficulty are reported. Both Infit and Outfit statistics showed a good fit between the data and the Rasch model. Conclusions The analysis provides evidence to support the validity and reliability of this instrument as a CCK test of soccer. Limitations of the study were discussed and suggestions were provided to improve the test.
Purpose The purpose of this study is to explore the Instructor’s adaptation process of school P.E. environment in middle school sports club and to develop substantive level theory. Methods For this purpose, 17 sports instructors who had worked for more than 3 years at the middle school in Seoul were selected as research participants. The method of this study is the Grounded theory(Strauss & Corbin, 1990). Results The results of this study are as follows. First, as a result of open coding, the instructor's adaptation process of the school P.E. environment was organized into 104 concepts, 30 sub-categories, and 15 categories. Second, as a result of axial coding, a paradigm model for the adaptation process of the school P.E. environment was formed. Third, as a result of the selective coding, created the storyline of the adaptation process and made the core category, ‘instructor's adaptation process of the school P.E. environment in middle school’. Four types of adaptation process such as 'Acceptance type', 'Effort type', 'Compromising type' and 'Abandoning type' are derived through the formalization applied to the hypothesis of the core category. Conclusions Based on these results, the developed substantive level theory was evaluated and summarized.
[Purpose] We examined the influence of reactive neuromuscular training (RNT) on golf swing coordination. RNT aims to induce proper coordinative movement by exaggerating the performer’s mistakes. Therefore, we applied RNT using inertia overloading to golfers who have problems with kinematic sequence during a golf swing. [Methods] To examine the effect of 12 weeks of RNT on golf swing coordination, we employed a ball tracking system (launch monitor) and motion analysis system (inertia sensors) were taken on four consecutive periods (pre-test and post-tests 4, 8, and 13 weeks later). Thirty Korean male cadets were divided into three groups based on inertial loading and practiced 7-iron golf swings combined with specific group tasks twice per week. [Results] At pre-test, most participants reached maximal angular velocity near the impact timing (95-100%). However, the deceleration timing of the maximum angular velocity of the proximal segments gradually moved toward mid-downswing as the training sessions proceeded, with the RNT group ultimately outperforming the two control groups. Additionally, the RNT group showed a significantly higher maximum angular velocity in the thorax and wrist. [Conclusion] Our results suggest that RNT can be sufficient to elicit and effective whole-body coordination pattern. Considerable follow-up research is needed on the use of RNT for various sports tasks and the effects of expertise on RNT results.
Purpose The purpose of this study was to examine the influence of coaches’ emotional leadership on athletic satisfaction and to investigate mediating effect of intrinsic motivation perceived by professional female basketball athletes in Korea and Japan. Methods 154 professional female basketball athletes in Korea and Japan participated in this study and responded to questionnaires which consisted of coaches’ emotional leadership, intrinsic motivation, and athletic satisfaction. The collected data were analyzed by frequency analysis, confirmatory factor analysis, reliability analysis, descriptive statistical analysis, correlation analysis, and structure equation analysis with using SPSS 23.0 and AMOS 23.0. Results The results of this study were as follows; Firstly, coaches’ emotional leadership had positive effect on athletic satisfaction. Secondly, coaches’ emotional leadership had positive influence on intrinsic motivation. Thirdly, intrinsic motivation had positively affect on athletic satisfaction. Lastly, intrinsic motivation completely mediated the relationship between coaches’ emotional leadership and athletic satisfaction. Conclusion In conclusion, these findings imply that coaches’ emotional leadership and intrinsic motivation are critical factors for improving athletic satisfaction.
Purpose The purpose of this study is to analyze the performance contents of men's floor exercise and to provide basic materials for achieving excellent results at world competitions. Methods Teams ranked 1 - 12 who participated in the World Championships' floor movement group competition selected a total of 59 players by the convenience sampling method and carried out technical statistics, frequency analysis, member variable variance analysis, and post hoc analysis. Results First, as a result of frequency analysis of the difficulty of each group, all the teams ranked 1 to 12 liked the most difficulty of C and found that they do not like the F difficulty the most. Secondly, there was a difference in average for each group's start score, ranking 1st to 4th> 5th to 8th> 9th to 12th place. Thirdly, there was a difference in average of difficulty levels for each group B, C, E, and it became very significant with E difficulty.Results of post hoc analysis B difficulty (9th to 12th> 1st to 4th, 5th to 8th), C difficulty (9th to 12th> 1st to 4th), E difficulty (1st to 4th> 5th to 8th ·9th to 12th). Conclusion These results show that in floor exercise, the art of more than C difficulty and the connection technology of A, B, C, difficulty, E and F, difficult difficulty such as difficulty, creative and dynamic performance composition is excellent It clearly states that it is a condition for getting results.
Purpose The purpose of this study is to investigate the effects of grip width and hand orientation on muscle activities of upper body during the lat pull-down. Methods Eight healthy men performed the 6 grip variations (3 grip width × 2 hand orientation) using an experimentally determined load of 70% of 1 repetition maximum. Five trials were analyzed for each grip type. Participants maintained a cadence of 2-second concentric and 2-second eccentric phases. The grip widths were normalized for each individual by using their biacromial diameter (100%), and then set the grip width 50% of biacromial diameter and 150% of biacromial diameter. Surface EMG of the latissimus dorsi, pectoralis major, infraspinatus, biceps brachii, triceps brachii, rectus abdominis, erector spinae and middle trapezius was recorded, and the root mean square of the EMG was normalized, using a maximum isometric voluntary contraction. Results Latissimus dorsi showed higher muscle activities in 100% grip width than those of 50% grip width. Pectoralis major and rectus abdominis showed higher muscle activities in 50% and 100% grip width than those of 150% grip width. Middle trapezius showed higher muscle activities in 150% grip width than those of 50% grip width. Conclusions Two-way repeated measures ANOVA for each muscle revealed that latissimus dorsi and middle trapezius (the posterior muscles of trunk) showed higher muscle activities in wide grip, on the other hand, pectoralis major and rectus abdominis (the posterior muscles of trunk) showed higher muscle activities in narrow grip.
