PURPOSE This study aimed to investigate the effects of trunk stabilization exercise (TSE) with abdominal expansion maneuver (AEM) that lasted for 8 weeks on postural stability and functional movement in college athletes. METHODS Twenty college athletes participated in the program (AEM=9, Control=11) and were subjected to 8-week TSE. The AEM group performed exercise by applying AEM techniques during TSE, and control group performed TSE without breathing-related instructions. Both groups measured postural stability with lower-quarter Y-balance test (LQYBT) and functional movement with functional movement screen (FMS) before and after applying TSE to verify the interaction before and after this study with the two groups. Two-way repeated analysis of variance was performed to evaluate the differences between groups and time for an absolute value of LQYBT and FMS, followed by Bonferroni’s multiple comparison tests for post-hoc analysis. RESULTS As a result of the left and right LQYBT, there was a significant difference between the time x group (p=.041, p=.033), and post-hoc analysis indicated that there was a significant difference between the AEM and control groups (p=.000, p=,000). Furthermore, the FMS total score indicated that there was a significant difference between the time × group (p=.039), and the post-hoc analysis showed the AEM group had significant results (p=.001), while there were no significant results in the control group (p=.255). CONCLUSIONS Application of AEM during TSE seems to be effective with regard to postural stability and functional movement in college athletes.
Purpose The purpose of this study was to evaluate the effect of detachable forefoot outsole on muscle activity of the lower extremity during downhill walking. Methods Thirteen male university students (age: 23.5±2.1 yrs, height: 175.7±4.6 cm, weight: 651.9±55.5 N) who have no musculoskeletal disorder were recruited as the subjects. Each subject walked down 20° ramp with forefoot’s design for the detachable outsole’s angle(5°, 10° and 20°) and type(A and B). To assess the myoelectric activities of selected muscles, six of surface EMG(QEMG8, Laxtha Inc. korea, sampling frequency = 1,024 Hz, gain = 1,000, input impedance > 1012 Ω, CMRR > 100 dB) electrodes with on-site pre-amplification circuitry were attached to ES, RF, BF, TA, LG, and MG. For each dependent variable, two-way ANOVA with repeated measures was used to determine whether there were significant differences among forefoot’s design for the detachable outsole’s angle and type (p<.05). When correlation effect was not statistically significant, post hoc analyses were performed using the multiple comparison through bonferroni, and if correlation effect was statistically significant, one-way ANOVA was performed as for the form of outsole which is an inter-group variable in order to find out simple main effect, and the paired t-test was performed to find out the angle of outsole, which is an intra-group variable. Results In IDLS phase, In terms of Rectus Femoris, 10°-B outsole showed statistically higher muscle movement than 5°-B, 5°-A outsole showed statistically higher muscle movement than 5°-B, 20°-A outsole showed statistically higher muscle movement than 20°-B. Among these outsoles, Conclusion 5°-B outsole was found to the most useful outsole for improving stability and controlling the bodily movement due to the body weight load when walking down the ramp.
The purpose of this study was to investigate basal physical fitness and smash speed of elite national badminton players. To perform this study, total forty six korea national badminton player were participated : twenty two male players(age : 20.90±2.24years, height : 179.30±5.40cm, weight : 73.80±7.12kg, career : 11.27±1.88years) and twenty four female players(age : 19.45±1.95years, height : 167.83±4.36cm, weight : 61.39±3.60kg, career : 9.50±2.47years). Each subjects performed the 6 basal physical fitness trials : agility, muscular endurance, muscular strength, flexibility, balance and cardiorespiratory endurance. And the speed of badminton smash were analysis by using radar gun when players were standing smash success. To determine the difference between two groups, independent samples test was used. As a result, we found that there was a large difference male players and female players in basal physical fitness and smash speed. First, male players were significantly strong in agility(side step 10%), muscular endurance(repetitional jump 12%), muscular strength(left grasping power 3%, right grasping power 31%) and cardiorespiratory endurance(20m suttle run 31%). On the other hand, female players were relatively strong in flexibility(sit and reach 27%) and balance(standing on one leg with eyes closed 51%). Second, maximum smash speed show that male players were about 57km/h(24%) faster than female players(male : 247.72km/h, female : 190.37km/h). Based on the findings, we shall be applicable training program to improve flexibility, balance of male athletes and agility, muscular endurance, muscular strength, and cardiorespiratory endurance of female athletes. our results will be appliable to improve the athletic performances of national badminton players by the coaches in the future.
PURPOSE This study investigated weight-class-related strength parameters during pulling performance in the ssireum. METHODS Elite ssireum athletes participated, 24 divided into four weight classes of six athletes each. They performed a pulling task while gripping a tube fixed to a three-axes load cell sensor, standing on force plate platforms. The test involved 30 repetitions at maximal force with the legs bent, the ssireum’s typical posture. Maximal force (Fmax), time to maximal force (TFmax), time difference between maximal forces (TDmax), and horizontal and vertical angles at maximal force (HAmax and VAmax, respectively) were analyzed from the load cell sensors. Ground reaction force (GRF) was collected, including peak force along the three axes, the resultant force, and the center of pressure (COP). One-way ANOVA tests were conducted to compare among weight classes (α=.05). RESULTS Fmax measured by load cell showed significant difference between classes (p<.05), indicating that the second weight group (Geumgang class) generated more pulling force than the heavier classes. In GRF results, lightweight classes demonstrated larger COP difference between the left and right plates. Specifically, the Geumgang class showed more movement in the anterior-posterior (AP) direction on the left plate. The peak GRF in the right plate of the AP (p<.001) and ML (p<.05) directions showed significant differences between lighter and heavier weight classes. CONCLUSIONS The Geumgang class generated greater pulling force, and the lighter classes demonstrated more leg contribution. Force generation did not solely depend on body mass; instead, lighter athletes often relied on the lower limbs to compensate for their limitations, a strategy commonly observed in competitions.
PURPOSE This study analyzed the relationship among coaching behaviors, motivational climate, sports competence, effort, and failure tolerance as perceived by high school athletes. Additionally, it examined whether motivational climate, competence, and effort mediate the relationship between coaching behaviors and failure tolerance. METHODS Using questionnaires measuring autonomy-supportive coaching behavior, controlling coaching behavior, motivational climate, sports competence, effort, and failure tolerance, 365 high school athletes were surveyed. Using SPSS 28.0 and Amos 28.0 software, descriptive statistics and structural equation modeling were conducted along with the following types of analyses: reliability, correlation, confirmatory factor, convergent validity, and discriminant. Additionally, the bootstrap method was used to verify serial multiple mediating effects. RESULTS Autonomy-supportive behavior had a significant positive effect 1) on motivational climate, sports competence, and effort and 2) on failure tolerance. 3) Controlling coaching behavior had a significant negative effect on motivational climate and sports competence. 4) Motivational climate and 5) sports competence both had a significant positive effect on effort. 6) Effort had a significant positive effect on failure tolerance. Last, in the relationship between autonomy-supportive behavior and failure tolerance, motivational climate, sports competence, and effort showed partial mediating effects. CONCLUSIONS This study confirms the importance of coaches’ autonomy-supportive behavior in determining failure tolerance among adolescent athletes. Based on this information, counseling (educational) programs aimed at enhancing performance can be developed and provided in sports settings, thus fostering success among athletes.
PURPOSE This study analyzed the effect of dynamic lumbar kyphosis on the biomechnical factors affecting the lumbar joints during deep squats. METHODS Thirty adults in their 20s who had experienced weight training for more than one year participated in this study (age: 23.4±3.5years old, height: 175.3±4.3cm, weight: 75.8±6.5kg, squat single repetition maximum (1RM) weight: 115.3±19.5kg). Under both restricted dynamic lumbar kyphosis (RDLK) and dynamic lumbar kyphosis (DLK), subjects completed one repetition of deep squats at a load of 70% of their 1-RM weight. To verify the consistency of deep squat movements performed under DLK and RDLK conditions, intra-rater reliability was analyzed using intra-class correlation . The biomechnical variables of the lumbar joint were calculated during DLK and RDLK deep squats. Paired sample t-tests (IBM SPSS 27.0, Armonk, New York, USA) were used for statistical verification. RESULTS During the deep squat movement performed in DLK and RDLK conditions, the peak angles of the ankle, knee, and hip joints, the minimum height of the pelvis, and the time and tempo showed statistically high reliability, confirming the accuracy of the movement. The peak flexion angle and moment, left flexion moment, left rotation moment, and compression force factors of the lumbar joint during deep squat were significantly lower in RDLK than in DLK. CONCLUSIONS Restricting lumbar dynamic kyphosis during deep squats is essential for decreasing the risk of lumbar joint injury.
PURPOSE This study aimed to present the measures necessary to perform well in tennis clubs by examining the adaptation process of the MZ generation participating in tennis clubs. METHODS A qualitative case study was performed and data was collected through in-depth interviews, direct observations, and literature surveys. The data were analyzed by applying pattern matching among the analysis methods proposed by Yin (2014), and the reliability and validity of the study were demonstrated by consultations between colleagues, reviewing members, and comparing and analyzing previous studies. The study participants were seven MZ generation tennis club participants selected through snowball sampling (one of the non-probability samples). RESULTS Achieving a level of skill that allows for compatibility and the effort required for it, the acceptance of differences in club culture and between generations, having the etiquette necessary for Generation MZ, and falling for the charm of tennis itself were identified as factors for successful participation in tennis clubs. CONCLUSIONS This study is expected to help the MZ generation, who have recently been interested in tennis, continue their participation, as well as lay a small foundation for the expansion of the base of the sport by detailing the measures necessary to successfully participate in tennis clubs.
PURPOSE The purpose of this study was to analyze the effect size of the unified theory of acceptance and use of technology (UTAUT) in the sports field using a meta-analysis. METHODS After identifying related studies by using RISS, 22 articles were selected and used to analyze the relationship between UTAUT sub-factors (performance expectancy [PE], effort expectancy [EE], social influence [SI], and facilitating conditions [FC]) and intention to use via the comprehensive meta-analysis program. RESULTS The results are as follows: First, the effect size between PE and intention to use was 0.521. Second, the effect size between FC and intention to use was 0.514. Third, the effect size between EE and intention to use was 0.500. Finally, the effect size between SI and intention to use was 0.475. CONCLUSIONS Diverse strategies can be derived to increase consumers' intention to use in the sports field using the UTAUT model.
PURPOSE The purpose of this study is to analyze the biomechanical variables involved in ballet dancers’ ankle muscle imbalance when performing relevé movements. METHODS The subjects of this study (n=14, age: 22.29±1.73 years old, height: 161.4±5.06cm, weight: 51.88±7.51kg) were 14 ballet dancers with 9 years of experience. Based on the reciprocal muscle strength ratio, the dancers were divided into the following groups: Close to the normal value (RMIS) and far from the normal value (RMIB) using the maximum values of plantar flexion and dorsiflexion of the ankle joint using an isokinetic measurement equipment (60°/sec). RMIB). The biomechanical variables, namely the ankle joint movement and ground reaction force, were subsequently measured. SPSS 26.0 was used for data analysis and independent t-test was used for statistical verification. RESULTS The ground reaction force in the Z (vertical) direction based on the ankle joint muscle strength imbalance of ballet dancers was significantly lower in the RMIB group. In addition, although it was not a statistically significant difference, the plantar flexion movement was lower in the RMIB group, and there was a significant difference in the generation of ankle joint movement in the Z direction. CONCLUSIONS In conclusion, in order for a ballet dancer to efficiently utilize the force generated from the supporting leg when performing a movement, ankle imbalance must be taken into consideration when training.
This study aimed to explore elite taekwondo competitors’ imagery strategies . The study participants were 10 elite taekwondo athletes, who worked for S business team. Data were collected through open-ended questionnaires and in-depth interviews. The data were collected based on Gould et al. (1992)’s proposed qualitative research method. The inductive content analysis of the imagery was conducted following the imagery type of Paivio (1985) and Suinn (1996). The law data and case of imagery were separated by three specialists. The results were as follows. First, elite taekwondo competitors generally used the types of imagery proposed by Paivio (1985) and Suinn (1996). In particular, imagery of anxiety regulation appeared with the highest frequency among factors and ordered imagery of motivation, imagery of skills, imagery of mental skills, and imagery of competition. Second, elite taekwondo competitors mainly used imagery of skills before two weeks for competition. They mainly used imagery of anxiety regulation the day before a competition. They used imagery of anxiety regulation and imagery of motivation on the day of a competition. They used imagery of motivation after the competition. In sum, elite taekwondo competitors used individual strategies in terms of imagery in order to ensure effective training and peak performance in competition. The strategy of imagery was applied differently based on the juncture of the competition.
