• Journal of the Korean Applied Science and Technology
• /
• v.35 no.3
• /
• pp.914-924
• /
• 2018

The purpose of this study is to provide the basic data for the shoulder strengthening exercise by analyzing the% MVIC of the muscle activity in the shoulder rotator cuff by the difference of the stance posture and the anatomical plane. 8male subjects were randomly assigned to perform the shoulder rotation exercise 10 times on the frontal plane, the horizontal plane, the sagittal plane and the two legs stance posture, the one leg stance posture, the lunge posture. Measured muscle activity of supraspinatus, infraspinatus, teres minor, anterior deltoid, rectus abdominis, erector supinea, pectoralis major, lattisimus dorsi during exercise. A repetitive one-way ANOVA was performed using the SPSS 22.0 statistical program. First, during the external rotation on the frontal plane, the erector spinea was higher in the lunge posture than in the two legs stance posture and the one leg stance posture, And during the internal rotation on the frontal plane, the muscle activity of suprapinatus was higher in one leg stance posture than in the two legs stance posture and more so in the lunge posture. Second, during the external rotation on the horizontal plane, the muscle activity of deltoid anterior was higher in the one legs stance posture and in the lunge posture than in the two legs stance posture, and during the internal rotation on the horizontal plane, the muscle activity of infraspinatus was higher in the lunge posture than in the two legs stance posture and one leg posture, and the muscle activity of pectoralis major was higher in two leg stance posture than in the one legs stance posture and more so in the lunge posture. Third, during the external rotation on the sagittal plane, muscle activity of rectus abdominis was higher one leg stance posture in the lunge posture than in two leg stance posture. During the internal rotation on the sagittal plane, muscle activity of supraspinatus was higher one leg stance posture in the lunge posture than in two leg stance posture. And muscle activity of infraspinatus was higher in the lunge posture than in two leg stance posture, one leg stance. And muscle activity of Rectus abdominis was higher in the lunge posture and one leg stance posture than in the two legs stance posture. And muscle activity of Erector spinea was higher in the two legs stance postur and lunge posture than in the one leg stance posture. In conclusion, the differences in stance and shoulder anatomy have different effects on the muscle activity of the shoulder rotator exercises, and this is expected to be a more positive exercise program when applied to the shoulder strengthening exercise program.

• Physical Therapy Rehabilitation Science
• /
• v.9 no.1
• /
• pp.18-24
• /
• 2020

Objective: The purpose of this study was to compare the activities of the abdominal muscles according to trunk stabilization exercises using Swiss ball in normal individuals. Design: Cross-sectional study. Methods: Ten healthy university students participated in this study. The subjects were required to complete the following three exercise positions: Exercise position 1, sitting on a Swiss ball and lifting the legs; Exercise position 2, pushing to a plank position from an ending position; and Exercise position 3, push-up posture with the legs on a Swiss ball. Changes in the trunk muscle activities were estimated using Biometric electromyography (EMG). Activities of the dominant side internal oblique muscle (IOM) and external oblique muscle (EOM) were estimated in all participants. The maximal voluntary isometric contraction (MVIC %) was measured to standardize the EMG signals for the IOM and EOM during maximum resistance when sitting up with each shoulder pointing towards the contralateral pelvis with knees bent and both arms crossed on the chest for 5 seconds. Results: There was a significant difference in the activity of the internal and external oblique muscles between Exercises 1 and 2 and Exercises 1 and 3 (p<0.05). Furthermore, the IOM/EOM activity ratio was the greatest during Exercise 3 and the smallest during Exercise 1. IOM and EOM activities were the greatest during Exercise 2 with greater EOM activity. Conclusions: In future studies, it will be necessary to investigate muscle activities by supplementing the above-mentioned limitations during the stabilization exercise. The results of this study may be used as a basis for controlling the intensity and frequency of exercise while prescribing trunk stabilization exercises.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.8 no.8
• /
• pp.1271-1276
• /
• 2013

This study selected 22 male subjects to examine the maintenance period of static and ballistic stretching applied to rectus femoris, divided them into 11 static stretching group and 11 ballistic stretching group and analyzed changes in median frequency and in maximal voluntary isometric contraction before stretching and at 30 sec, 1 min, 3 min, 5 min, and 10 min after stretching. Median frequency showed significant differences in changes according to time and groups after the test of main effects. It was reduced after 3 min. in both static stretching and ballistic stretching groups and then increased again. Maximal voluntary isometric contraction showed significant differences in changes according to time and groups from the results of the main effect test. Static stretching group was reduced at 3 min after the experiment and then increased after that and ballistic stretching group was reduced at 5 min after the experiment and then increased again. In conclusion, changes were shown according to time after stretching and the effects of ballistic stretching were maintained a little longer than those of static stretching.

• The Journal of Korean Physical Therapy
• /
• v.21 no.3
• /
• pp.17-24
• /
• 2009

Purpose: The purpose of this study was to investigate the effects of a combination of isotonic (CI) technique on the balance, muscle fatigue and muscle activities of the quadriceps muscle in the paretic leg of hemiplegic patients. Method: All the subjects received a combined isotonic technique of proprioceptive neuromuscular facilitation (PNF) for about 30 minutes 3 times per week for 6 weeks. The root mean square (RMS) and mid frequency (MF) were recorded by surface electromyography (EMG)(EMG/EP system, OXFORD Medelec, UK) during maximal voluntary isometric contractions (MVIC). The balance ability was measured by a balance system (BIODEX, USA). Result: The RMS of the quadriceps muscle at post-treatment was significantly increased compared to that at pretreatment (p<0.05). Yet there was no significant difference among the three muscles. There were no significant difference in the MF of the vastus lateralis and rectus femoris between pre- and post-treatment, but the MF of the vastus medialis was significantly decreased (p<0.05). There was a significant difference in the vastus medialis and lateralis between pre- and post-treatment (p<0.05). Moreover, the overall stability index at post-treatment was significantly decreased compared to that at pre-treatment (p<0.05). But there was no significant difference between the anterior/posterior and medial/lateral stability indexes. Conclusion: The results of this study indicated that a CI technique of PNF had an effect to improve the balance and muscle activity in hemiplegic patients.

• Journal of Biomedical Engineering Research
• /
• v.44 no.4
• /
• pp.284-292
• /
• 2023

This study attempted to observe muscle activity and muscle fatigue among isotonic exercise of Biceps Brachii and Deltoidus Medius, which correspond to upper limb muscles, using metronome. For the experiment, 13 adult men participated to evaluate biosignals (ECG, EMG). For quantitative evaluation, 1RM and MVIC test were carried out and a constant pace isotonic excise session was conducted. Five sets of exercise were performed, and each set proceeded to the failure point while the speed condition (30bpm) was assigned. As a result of the experiment, muscle activity in both muscles was significantly reduced in fifth set compared to first set. Muscle fatigue has been confirmed to occur at a significant level within the set, but there was only a significant difference in both muscles in the first and second sets between sets. This is similar to the results of previous studies that gives the same rest time(2min), but further research is needed to see if the conditions for the number of repetitions are affected. Based on the recent increase of interest in muscle strength exercise, this study was conducted to observe the results by varying the conditions of common exercise.

• Journal of The Korean Society of Integrative Medicine
• /
• v.7 no.4
• /
• pp.33-41
• /
• 2019

Purpose : The muscle strength of iliopsoas (IL) was measured commonly in sitting position with hip and knee flexed 90°. However, there is no study to determine the muscle strength of IL in various test positions. Therefore, the purpose of this study was to compare the muscle strength of IL and muscle activity of rectus femoris (RF) according to test position and knee flexion angle. Methods : Twenty healthy subjects were participated for this study. The muscle strength of IL and muscle activity of RF were measured by hand-held dynamometer and surface electromyography during maximum voluntary isometric contraction (MVIC) of IL, respectively. The muscle strength of IL and muscle activity of RF was measured in 4 conditions as follows; 1) knee flexion angles 90 ° in supine, 2) 130 ° in supine position, 3) 90 ° in sitting, 4) 130 ° in sitting. Each condition were performed randomly by three repetitions. Results : The muscle strength of the IL was the main effect on the test position and knee flexion angle (p<.05), and the muscle activity of RF was the main effect only on the knee flexion angle (p<.05). There was also no interaction between the factors (p>.05). In supine position, the muscle strength of IL in knee flexion 130 ° was significantly less than that in knee flexion 90 ° (p<.0125). In knee flexion 90 °, the muscle strength of IL in supine position was significantly greater than that in sitting position (p<.0125). The muscle activity of RF in knee flexion 130 ° was significantly less than that in knee flexion 90 ° in supine and sitting positions (p<.0125). Conclusion : When the muscle strength of IL was measured in clinic and sports fields, the supine position with knee flexion 130 ° was recommended to prevent the muscle activation of RF and to maintain the trunk stability.

• The Journal of Korean Physical Therapy
• /
• v.30 no.1
• /
• pp.1-7
• /
• 2018

Objective: This study aimed to determine the efficacy of flexible pole training combined with lumbar stabilization in improving trunk muscle activities and to investigate the difference according to posture in young adults. Methods: Twenty-five participants were enrolled in this study. The subjects were randomly allocated into either the flexible pole group or the rigid pole group. Participants performed lumbar stabilization exercises on quadruped and curl-up, with the flexible pole or rigid pole. Electromyography was used to assess the percent maximal voluntary isometric contracion (%MVIC) of the rectus abdominis (RA), external oblique (EO), internal oblique (IO), and erector spine (ES) muscles. All participants completed one 30-minute session per day, 3 days per week, for 6 weeks. The evaluation was performed before and 6 weeks after the training, and follow-up. The data were analyzed using independent t-test and two-way repeated measure analysis of variance to determine the statistical significance. Results: The flexible pole in curl-up showed significant differences in EO and IO muscle activities compared with the rigid pole. The flexible pole in quadruped showed significant differences in IO and ES muscle activities compared with the rigid pole. The RA, EO, IO, and ES muscle activities of both groups were significantly higher after 6 weeks training. Conclusion: The flexible pole in curl-up and quadruped showed an improvement in trunk muscle activation. The flexible pole combined with lumbar stabilization will be useful as an exercise tool to improve activity of trunk muscles.

• Physical Therapy Rehabilitation Science
• /
• v.11 no.2
• /
• pp.253-258
• /
• 2022

Objective: This study aimed to determine the effect of internal abdominis pressure(normal, hollowing and bracing) on trunk muscle activity during one leg bridge exercise. Design: Cross-sectional study. Methods: Thirteen healthy adults (9 men and 4 women) were instructed to perform Internal abdominal pressure(IAP) control(Normal, Hollowing, Bracing) during one leg bridge. Electromyography (EMG) data (% Maximum Voluntary Isometric Contraction, MVIC) were recorded three times on both sides of the participant's Internal Oblique(IO), Effector Spinae(ES), and Multifidus(MF) muscles and the average value was analyzed. Results: As a result, Abdominal bracing one leg bridge (BOLB) group and Abdominal hollowing one leg bridge (HOLB) group showed significantly increased muscle activation of bilateral internal oblique, erector spinae and multifidus activation compared to the Normal one leg bridge (NOLB) group (p<0.05). Abdominal hollowing one leg bridge (HOLB) group had a significant difference in bilateral Internal oblique muscle activation in compared to the NOLB group (p<0.05). Conclusions: Bilateral internal oblique, erector spinae, and multifidus muscles activation in healthy adults at one leg bridge exercise showed greater activation at abdominal bracing. Therefore, in this study, IAP control can be used as an indicator of choice to the dysfunction with trunk muscle weakness and corrective exercise subject's situation when the goal is to activate the trunk muscles by performing one leg bridge.

• Journal of International Academy of Physical Therapy Research
• /
• v.5 no.2
• /
• pp.757-763
• /
• 2014

The purpose of this study is to observe the effect of elasticity of taping on ankle muscles'activity and endurance after plyometric training that easily causes ankle injury, and provide baseline data for physical therapy intervention methods. The study subjects are 24 male students in their 20s who attend N University in Choongnam. They were divided into three groups; 8 subjects in the elastic taping group, 8 in the non-elastic taping group, and 8 in the non-taping group(control group). They had plyometric training for 6 weeks. After the training, this study measured their maximum voluntary isometric contraction(MVIC) and muscle endurance of the muscles around ankle joint. The experiment result is as follows. After the training, all three groups showed improvement in muscle strength and endurance. The elastic taping group showed insignificant improvement in muscle strength but significant increase in muscle endurance in plantarflexion. In dorsiflexion, both muscle strength and endurance increased significantly. The non-elastic taping group showed insignificant improvement in muscle strength but significant increase in muscle endurance in plantarflexion. Taping during plyometric training had a little or insignificant effect on muscle endurance and strength compared to the non-taping group.

• Journal of The Korean Society of Integrative Medicine
• /
• v.11 no.4
• /
• pp.213-220
• /
• 2023

Purpose : The purpose of this study is to investigate the effect of each lower trapezius muscle exercise performed according to the abduction position (Y type - shoulder joint abduction 145 °, T type - shoulder joint abduction 90 °, and MPC type - shoulder joint 45 ° abduction) of the shoulder joint on the muscle activity of the round shoulder and lower trapezius muscle. Methods : This study was conducted on 31 adult men and women. Through random assignment, they were assigned to the Y group, T group, and MPC group. A 4-week intervention was performed for each group of 31 subjects who participated in the experiment, and shoulder height and lower trapezius muscle activity were measured before and after the intervention. Shoulder height measurement is a test to measure rounded shoulder posture. When the value is low, it means that rounded shoulder posture is improved. The muscle activity of the lower trapezius muscle was measured using the %MVIC method, and when the value is high, it means that the lower trapezius muscle is active. All measured data were verified using dependent t-tests for before and after comparisons and one-way analysis of variance for comparisons between groups. Results : The results of this study showed a significant decrease after intervention only in shoulder height. Muscle activity of the lower trapezius muscle decreased after intervention, but did not show a significant difference. Both variables showed no significant differences between groups. Conclusion : The results of this study show that three lower trapezius muscle exercises were performed on subjects in rounded shoulder posture. All three groups showed a significant decrease in the shoulder height value, a method of measuring rounded shoulder posture, and no significant differences between groups could be confirmed. Therefore, all three exercises can be considered effective in reducing shoulder posture.