• Journal of the Korean Applied Science and Technology
• /
• v.40 no.2
• /
• pp.342-347
• /
• 2023

The purpose of this study was to determine the comparison of upper arm, trunk and core muscle activities according to different performance in high Plank exercise using weightless exercise equipment. Six males(age, 23.00±0.73 years; height, 172.95±2.05 cm; body mass, 66.83±2.75 kg; and BMI, 22.33±0.72 kg/m²) completed this study as the subjects. Four type's high Plank exercises using weightless exercise equipment were performed(high plank, HP; high plank with air walker, HPAW; high plank with surf board, HPSB; high plank with waist trainer, HPWT). For the EMG analysis, we measured the body muscle activities of right side on the deltoid(DT), triceps brachii(TB), latissimus dorsi(LD), and external oblique(EO). This research's results were as follows. DT, TB, LD, & EO muscle activities were greatest during HPSB(p=.000). Therefore, these results are expected to serve as basic data for high Plank exercise using weightless exercise equipment performance applications in effective exercise programs.

• Journal of the Korean Orthopaedic Association
• /
• v.54 no.2
• /
• pp.91-99
• /
• 2019

Most patients experience pain relief and functional improvement after arthroscopic rotator cuff repair. In some patients, however, symptoms still remain after surgery. Failed rotator cuff repair is a complex outcome of biological, technical, and traumatic factors. Moreover, re-tears might or might not be the main cause for patients with persistent pain after rotator cuff repair. Therefore, a thorough understanding of the patient's history, physical examination, and appropriate imaging studies will be needed to evaluate and manage these patients. The patient's age, functional requirement, quality of the rotator cuff, preoperative range of motion, quality of the deltoid, and glenohumeral arthritis are factors to consider before performing revisional rotator cuff repair. Preoperative patient education is as important as the surgical technique for successful revisional rotator cuff repair.

• Journal of Oral Medicine and Pain
• /
• v.33 no.3
• /
• pp.279-294
• /
• 2008

This study aimed to make an analysis of the occlusion in the state of muscle fatigue produced by excessive mouth opening and clenching during the dental treatment to control the dental pain and to evaluate the sensory nerve in the muscle pain state. Most of the reasons why patients visit the dental office result in pain-either conceivably the dental origin pain or the non-dental origin pain. The dental offices have many therapeutic actions to produce the masticatory muscle fatigue for the treatment. Dental treatment with long minutes of mouth opening can cause some headaches, masticatory muscle pain and mouth opening difficulties. Patients with mastication problems who visits a dental office to alleviate pain run against another unexpected pain with other aspects. This study uses T-scan II system(Tekscan Co., USA) for the evaluation on the occlusal pattern in the experimental muscle fatigue after clenching, opening the mouth excessively and chewing gum. The occlusal contact pattern is analyzed by the contact timing, namely first, intercuspal, maximum and end point of contact. This inspection was performed at frequencies of 2000Hz, 250 Hz and 5 Hz before and after each experimental muscle pain was produced to 24 subjects who had normal occlusion without the orthodontic treatment or a wide range of the prosthesis by using $neurometer^{\circledR}$ CPT/C(Neurotron, Inc. Baltimore, Maryland, USA). The measuring sites were mandibular nerve experimental muscle fatigue respectively. This study could obtain the following results after the assessment of occlusion and sensory nerve of the experimental muscle fatigue. 1. There were the fastest expression after the excessive mouth opening in muscle fatigue and after tooth clenching in muscle pain. In the visual analog scale that records the subjective level, there was the highest scale after the clenching in the muscle fatigue in jumping off the point of pain. 2. Tooth contact time, contact force, relative contact force on the point of the first contact had no difference, and there were decreases in the contact force after the excessive mouth opening on intercuspal position point, after the excessive mouth opening and the gum chewing on the point of the maximum, and in the contact time after all the experimental muscle fatigue state on the point of the end contact. 3. There was no statistic significance in the current perception threshold before and after the experimental muscle fatigue. 4. There was no significant difference in the contact number, the maximal contact number on the point of the first contact, and the contact number after the mouth opening and gum chewing on the point of the intercuspal position and the contact number after the experimental muscle fatigue on the maximum point, and showed significant decreases. In conclusion, it was found that the occlusal pattern can cause the changes on the case of the clinical muscle weakness by intra-external oral events. It was important that the sedulous attention to details is required during dental treatment in case of excessive mouth opening, mastication and clenching.

• Journal of Digital Convergence
• /
• v.10 no.9
• /
• pp.435-441
• /
• 2012

This study is intended to provide a basic clinical data useful for preventing shoulder injuries related to occupation and curing them, by measuring the shoulder muscle activity of normal adults in an arm posture type of a wide shoulder joint angle, according to several differences of hand grip force. In order to examine the shoulder muscle activity during hand grips at a variety of intensity, according to the arm posture type, MVCs of all subjects were measured, and %MVCs of anterior deltoid, supraspinatus, the upper trapezius and infraspinatus at 0 degree, 90 degrees and 160 degrees of shoulder angle were yielded according to the grip force in an arm posture type, changing the maximum grip force into 30%, 50% and 90%, randomly. When measuring the hand grip at 30%, 50% and 70% of the maximum grip force to compare %MVC of each group depending on the arm posture type, there were no significant differences of muscle activity at 0 degree of shoulder angle among anterior deltoid, supraspinatus, the upper trapezius and infraspinatus, but there were significant differences of it among them at 90 degrees and 160 degrees of should angle(p<.001). According to the results of post-hoc test, also, anterior deltoid had the highest muscle activity, whereas the upper trapezius had the lowest muscle activity.

• Korean Journal of Applied Biomechanics
• /
• v.18 no.1
• /
• pp.85-95
• /
• 2008

This study is analyzing about application of taping by movement about shoulder joint's isometric contraction. M. college students take part in experiment. WEMG-8 and HUMAC system are used. Findings were as follows: EMG of muscle's MVIC at each angle before and after taping. 1. In flexion, EMG with taping is effective for supra spinatus at $0^{\circ}{\cdot}45^{\circ}{\cdot}90^{\circ}$, anterior deltoid at $0^{\circ}{\cdot}45^{\circ}$ and biceps brachii at $0^{\circ}{\cdot}90^{\circ}$. 2. In extension, EMG with taping is effective for triceps brachii at $0^{\circ}$, latissimus dorsi at $90^{\circ}$ and posterior deltoid at $45^{\circ}{\cdot}90^{\circ}$. 3. Each angle viewpoint, EMG of latissimus dorsi in extension can be arranged in its high order as $90^{\circ}<45^{\circ}$, $0^{\circ}$ without taping and $90^{\circ}<0^{\circ}$ respectively. EMG of posterior deltoid in extension is in its high order as $90^{\circ}<45^{\circ}<0^{\circ}$ without taping and $90^{\circ}<0^{\circ}$.

• Journal of Chest Surgery
• /
• v.32 no.5
• /
• pp.428-432
• /
• 1999

Background: It has been shown that low-grade electrical stimulus can transform fatigue resistant muscles which then can be used to protect the heart. The bulky and cumbersome power sources of the artificial heart or implantable ventricular assist devices are still in need of solution; however, on the other hand, the implantable ventricular assist devices using the resistant muscles as the power source have the advantages of using its own muscle contractions. The purpose of this study was to determine the possibility of a clinical application of the skeletal muscle ventricle. Material and Method: Latissimus dorsi muscles (LDM) of 8 canines were used for skeletal muscle ventricle. A latex chamber was wrapped one and a half times with LDM. The chamber was attached to a pressure transducer via Tygon tube. An electrode stimulator was placed around the thoracodorsal nerve and LDM was stimulated in cyclic bursts of 0.31 sec on time and 6.0 sec off time using 3.0 volt Itrel stimulator. The preload volume was added to the system in 25cc increments. Ejection volumes, pressures, and peak power outputs were measured. Result: Ejection volume was 76.3cc with 0cc of preload. Ejection volumes were less than 70ml with increments of preload over 75cc Pressures were more than 107 mmHg when the preloads were less than 75cc and less than 100 mmHg when the preloads were more than 100cc. Peak power output of 16.6 W/kg was observed at 50cc preload. Conclusion: Depending on the changes of preload, the volumes ejected from skeletal muscle ventricle and pressures from the skeletal muscle contraction surpassed those of the normal heart. These data suggest that there are clinical applications for skeletal muscle ventricular assist system.

• Journal of the Korean Applied Science and Technology
• /
• v.35 no.3
• /
• pp.905-913
• /
• 2018

The purpose of this study is to investigate the difference of muscle activity according to application of a foam roller during pilates. The 8 male subjects were selected and quadruped position, bridge, and core control movement of pilates were randomly assigned to 9 movements on a static mat motion, static foam-roller motion, and dynamic foam-roller actions. This program was conducted once at intervals of 1 week. The muscle activity of erector spinae, rectus abdominis, external oblique, gluteus medius, rectus femoris, and biceps femoris were measured and the collected data was analyzed by one-way ANOVA. First, in the quadruped, the rectus abdominis and external oblique, rectus femoris of the dynamic foam-roller actions showed higher muscle activity than the static mat motion and the static foam-roller motion(p <.001), gluteus medius muscle activity was also significantly higher (p <.05). biceps femoris were significantly higher in static foam-roller motions than in static mat-motion and dynamic foam-roller actions(p <.05). Second, biceps femoris muscle activity was highest in dynamic foam-roller actions than static mat-motion and static foam-roller motions during bridge(p <.001). Third, in the sitting core control, the rectus abdominis and gluteus medius of the dynamic foam-roller actions showed higher muscle activity than the static mat motion and the static foam-roller motion(p <.001). and activity of erector spinae muscle was also significantly higher (p <.01). external oblique were significantly higher in static mat-motion than in static foam-roller motions and dynamic foam-roller actions(p <.05). Considering the muscle activity during pilates exercise, it would be more effective to apply the method and difficulty.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.22 no.1
• /
• pp.199-207
• /
• 2018

Experimental programs were performed to evaluate the flexural performance of fiber reinforced concrete(FRC) beams using a hybrid double-layer arrangement of steel bars and fiber reinforced polymer(FRP) bars or using FRP bars only. A total of seven beam specimens were produced with type of tensile reinforcing bar(CFRP bar, GFRP bar, steel bar) and the poly vinyl alcohol(PVA) fiber mixing ratio(0.5%, 0%) as variable. An analysis method for predicting the flexural behaviors of FRC beams with hybrid arrangement of heterogeneous reinforcing bars through finite element analysis was proposed and verified. In case of the specimens with the double-layer reinforcing bars, the test results showed that the first cracking load of specimen with a double-layer arrangement of steel bars was greater by 26-34% than specimens with a hybrid double-layer arrangement of steel and FRP bars. In maximum flexural strengths, the specimen that used CFRP bars as bottom tensile reinforcing bar showed the greatest strength among the specimens with the double-layer reinforcing bars. When the maximum moment value obtained through experiments was compared with that obtained through analysis, the ratio was 1.2 on average, the standard deviation was 0.085, and the maximum error rate was 22% or less. Based on these results, the finite element analysis model proposed in this study can effectively simulate the actual behavior of the beams with hybrid double-layer reinforcing bars.

• Clinics in Shoulder and Elbow
• /
• v.2 no.2
• /
• pp.170-177
• /
• 1999

The electromyographic activity of four muscles(biceps, supraspinatus, infraspinatus and subscapularis) was mea­sured from non-dominant shoulders of 12 volunteers by six different provocative test for the biceps pathology. The provocative tests were Speed, Yergason, Ludington, Heuter, O'Brien and the abduction-extension test. Each test was performed in a force of 30% of maximal voluntary contraction. The levels of activity of the biceps were higher than those of the other rotator cuff muscles only in Speed's test: 28% in the biceps, 26% in the infraspinatus, 25% in the supraspinatus and 21 % in the subscapularis. The levels of activity of the biceps as a percent of MMT(maximal manual test) were higher in Speed's(42%) and O'Brien's test with the arm supinatecl(42%). Speed's test can isolate the activity of biceps better than the other tests but it is a nonspecific test by which the biceps tendon was also activated within other rotator cuff muscles.

• Journal of the Korea Convergence Society
• /
• v.10 no.3
• /
• pp.67-72
• /
• 2019

The purpose of this study was to analyze the effects of computer game usage time on trunk muscle thickness and pressure pain threshold. The 33 study participants were divided into Group A, which spent less than 10 hours per week playing computer games; Group B, which spent between 10 and 20 hours per week playing computer games; and Group C, which spent more than 20 hours per a week playing computer games. The thickness of the participants' upper trapezius (UT), pectoralis minor (PM), anterior scalene (AS), and middle scalene (MS) muscles as well as the pressure pain threshold of their UT, PM, AS, MS, and levator scapular (LS) were measured. The study found that the PM, AS, and MS muscle thickness in group C was significantly greater than in the other groups (p<.05), and the UT, AS, PM, and LS pressure pain threshold in group C was significantly lower than in other groups (p<.05). Therefore, those who use computers for a long period of time during the week should recognize that their computer usage may cause musculoskeletal disorders.