The past few decades has seen increasing kinematic studies using surface electoromyography (EMG) in archery, however there has been no such specific study in Korean traditional archery. The purpose of this study was to evaluate EMGs during archery shooting motion in Korean traditional archers. Ten men Korean traditional archers were participated, and divided into two groups according to the shooting stance; parallel stance group(PSG, n=5) and oblique stance group(OSG, n=5). The surface EMGs were measured 12 muscles during shooting motion of five events including Junbi(Set), Geogung(Set up), Manjak(Full draw), Balsi(Release), Machigi(Ending). At the result, muscle activity of posterior deltoid, trapezius, rhomboid major, latissimus dorsi, biceps brachii, forearm extensor bundle, triceps brachii, levator scapulae significantly increased at event of full draw and release, then significantly decreased again at event of ending, respectively(p<.01, p<.001). The muscle activity of erector spinae(ES) was also significantly increased at event of full draw and release(p<.01, p<.001), while no significant changes in muscles of rectus abdominis, rectus femoris(RF), gluteus maximus. As a result of comparing PSG and OSG, muscle activity of RF in OSG was higher than PSG at event of release(p<.05), it remained until event of ending(p<.05). On the other hand, the higher the tension of the bow, the higher the muscle activity of the draw arm at event of release(p<.05). These results suggest that when Korean traditional archery shooting, both side arm and back muscles are more activated than the abdomen, leg and hip muscles. The parallel stance might suppress the muscle activity of the lower extremities to twist the upper body. And the higher bowstring tension needs to increase of muscle strength in BB of draw arm.
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 analyze the effect of push-up plus exercise(PUPE) on stabilization of the scapula and to use it as basic data for shoulder rehabilitation program. Methods In this study, research papers were collected using Research Information Sharing Service(RISS) and Pub-Med Central.(PMC) as a search term for scapular stabilization, push - up plus, shoulder joint injury rehabilitation and scapular stabilization exercise. Also, it was used as basic data of literature analysis. The collected data were classified into the structure and movement of the scapula and shoulder, kinesiologic relation of the scapula and the mechanism of injury, and the effect of push-up plus Results Serratus anterior is a typical stabilizing muscle, and it forms a force couple with the upper and lower trapezius to control the movement of the scapula. The PUPE is an effective exercise method to selectively strengthen serratus anterior, which are the stabilizing muscles of the scapula, and is an exercise method that is also useful for correcting the wrong postures and movements because of hypertonus upper trapezius. In addition, various conditions such as application posture, arm position, and ground instability were suggested during PUPE. Conclusion The results of this study confirmed that PUPE is an effective program for scapula stabilization in the rehabilitation of shoulder injuries and injured patients and athletes. The PUPE will be used as a rehabilitation exercise program for patients and athletes who need rehabilitation of the shoulder joint.
Purpose The purpose of the study was to investigate the effect of vibratory stimulus on the static postural control of 8 healty senior adults. Methods To achieve this goal, all subjects participated in two different kinds of static postural control tasks. Task 1 was a static postural control task, where both-legs stand on the ground. Second task was an unstable static postural control task using only single leg stance. As they maintain their balance, 6 different vibratory stimulus were provided on the sole of their feet(personal threshold 0%, 80%, 90%, 100%, 110%, 120%). Results The results of the study were as follows: First, there was no significant differences in postural control ability according to different types of vibrator intensity. Second, there was a significant difference in single-leg postural control ability according to vibrator intensity. Third, there was a significant difference in anterio-posterior stability according to the different types of vibrator intensity. Conclusion Stochastic resonance using vibratory stimulus was more effective in the single leg stance task, rather than the double leg stance task. Moreover, sub-threshold vibratory stimulus(80%, 90%) intensity were more effective than higher vibratory stimulus(100%, 110%, 120%).
PURPOSE This study aimed to analyze the dynamic posture stabilization and kinematic variables between visual feedback and Y-balance training groups during jump-landing. METHODS Thirty-eight male players (age: 22.6 ± 1.12 years, height: 175 ± 3.54 cm, weight: 65.5 ± 5.11 kg) were included in this study, and chronic ankle instability was checked using Cumberland Ankle Instability Tool (CAIT) and Balance Error Scoring System (BESS). They were randomly assigned to the Visual biofeedback (Training group: TG, n = 19) and Y-balance groups (Control group: CG, n = 19) for four weeks. TG performed balance training using the Biodex balance system (BBS) and CG performed training using the Y-balance system. During jump landing, time to stabilization (TTS), force plate (COP, GRF); joint angle and moment were collected and analyzed. All analyses were performed with SPSS 21.0, and Bonferroni was used for repeated measured ANOVA and post-hoc. RESULTS The results indicated that there was an interaction between TG and CG in terms of AP and ML directions of TTS (p < 0.05). AP/ML TTS of the TG for the post-test was smaller than that for CG (AP: p = 0.000; ML: p = 0.046). ML TTS of the TG for post-test was smaller than at pre-test (p = 0.041), and AP TTS of the CG for ankle joint moment (p < 0.05). There was an interaction between TG and CG in terms of dorsiflexion (DF) and plantarflexion (PF) of joint moment (p < 0.05). Ankle moment of the CG for post-test decreased than at pre-test (DF: p = 0.040, PF: p = 0.032), and ankle dorsiflexion moment of the CG for post-test was decreased than at pre-test (p = 0.046). CONCLUSIONS Balance ability was achieved more effectively through visual biofeedback training than Y-balance training. Therefore, we recommend balanced training with visual feedback on chronic ankle instability.
Purpose : The purpose of this study was to investigate coaching information with which coaches provided players during badminton competition. Methods : To this end, we generated an open-ended questions and presented it to 88 high school athletes registered in the Badminton Korea Association. The survey was conducted during a tournament and immediately after the tournament to collect the data. The collected data were categorized through inductive content analysis. Results : As a result of this study, a total of 480 raw data points collected through the open-ended survey were categorized into four general areas: psychological information, technical information, tactical information, and game operation information. Specifically, psychological information was divided into six subdivisions: concentration, confidence, relaxation/stabilization, mental toughness, play thought, and passion; technical information was broken into four subdivisions: strokes, footwork, swing and posture, and position preparation; tactical information had four subdivisions: coping to opponents, play changes, rotation, and manipulation of opponents; and, game operation information was divided into two subdivisions: taking the lead in a game and changing atmosphere. Conclusions : In other words, in badminton competition, the coaches strengthened psychological skills that promote psychological stability to attain the athletes’ peak performance and modified the athletes’ motion into the action necessary for achieving accurate techniques. Furthermore, they provided a variety of coaching information so that the athletes will respond appropriately to their opponents’ play, take the lead in games and induce a positive mood. The psychological, technical, tactical and game operation information offered by badminton coaches are the main factors influencing the performance of badminton players and suggest a need for the proper management and control of the coaches as well as athletes for the peak performance.
Purpose This study was to analyze and compare series of muscle activities during plank exercises with use of togu-jumper. Methods Ten male subjects (age 26.9±1.7 yrs, height 172.2±5.7 cm, weight 66.5±7.5 kg) who have no musculoskeletal disorder with one's upper or lower limb were selected as subjects. To analyze and compare series of muscle activity, five of surface EMG electrodes were attached to the upper rectus abdominis (URA), lower rectus abdominis (LRA), external abdominal oblique (EO), erector spinae (ES) and gluteus maximus (GM). Each subject did plank exercise on stable support surfaces (normal surfaces) and unstable support surfaces with the togu-jumper. For each dependent variable, one-way ANOVA with repeated measures were performed with significance level p<.05. Contrasts were performed to execute post tests for results with statistical significance. Results The study showed that the average IEMG values of URA and LRA increased in Upper (Togu-jumper used upper limb) compared to normal surfaces. This is perhaps because the effects of URA more than any other muscles for body stability. Furthermore, the peak IEMG values of LRA increased in Upper and Lower (Togu-jumper used lower limb) compared to normal surfaces. In addition, peak IEMG values of EO increased in Upper compared to Normal. This may have resulted due to momentary strong muscle activity in LRA and EO to correct body posture and balance. Therefore, using Togu-jumper on upper limb maximizes the performance of core training in plank exercise. Conclusions The study may be further applied to a method for effective training. It is considered that research and analysis has to be further done on modified plank exercise. Additionally, it is necessary to analyze not only global muscle but also local muscle, as a comprehensive research, to suggest ideal method for plank exercise.
