• 한국안전학회지
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• 제27권1호
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• pp.111-116
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• 2012

Workers who work with his neck bent backward in the standing posture have often complained of their musculoskeletal stress. The objective of this study was to find how much stress there was for workers who worked with their neck bent backward. The subjective evaluation and electromyography(EMG) were used to check the level of the stress. It was found that all subjects felt extreme pain after working with the neck bent backward and alternating 1 minute work and 0.5 minute rest for 30 minutes. The EMG level(amplitude) of neck muscles increased 80 percent on the average and the center frequency of EMG shifted to the lower frequency level which indicated fatigue of neck muscles. Thus, the intervention of this musculoskeletal stress is strongly recommended.

• 대한물리의학회지
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• 제4권1호
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• pp.15-21
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• 2009

Purpose : The purpose of this study was to find the effect of ankle joint angle on knee extensor electromyographic activity following knee extension exercise. Methods : Ten male university students participated in the study. The subjects performed isometric maximal voluntary knee extensor contractions (MVC) and knee extensor EMG activity measured in with three different ankle joint angle. The EMG activity of rectus femoris(RF), vastus medialis(VM), vastus lateralis(VL) were measured using surface electromyography. Results : EMG activity of vastus lateralis following the change of ankle joint angle was shown statistically significant difference. Conclusion : Ankle plantar flexion position increase EMG activity of vastus lateralis during knee extension exercise.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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• pp.115-115
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• 2000

A gait pattern classification method using electromyography(EMG) signal is presented. The gait pattern with four stages such as stance, heel-off, swing and heel-strike is analyzed and classified using feature parameters such as zero-crossing, integral absolute value and variance of the EMG signal. The EMG signal from Tibialis Anterior and Gastrocnemius muscles was obtained using the surface electrodes, and low-pass filtered at 10kHz. The filtered analog signal was sampled at every 0.5msec and converted to digital signal with 12-bit resolution. The obtained data is analyzed and classified in terms of feature parameters. Analysis results are given to show that the gait patterns classified by the proposed method are feasible.

• 대한의용생체공학회:의공학회지
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• 제32권4호
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• pp.328-335
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• 2011

For human factor engineering and wearable robot design, the quantitative assessment of physical workload is needed. Through measuring the surface EMG (sEMG) and analysis, the physical workload in overhead lifting posture is presented in quantitative manner. By normalizing sEMG activities with maximal voluntary contraction (MVC), the inter-subject variability is reduced. In all muscles, %MVC increased as the weight of lifting object increases. In anterior deltoid muscle, the %MVC was 3-4 times higher than the other muscles which imply that this muscle performs the major role in the overhead lifting posture. In fatigue analysis, %MVC and the mean frequency in muscle of anterior deltoid changed markedly when compared with other muscles. Through the suggested procedures and analysis, the physical workload for a specific posture can be represented in quantitative way but the clinical meaning for the value should be investigated further.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2002년도 추계종합학술대회
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• pp.378-381
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• 2002

본 논문에서는 근전도(EMG) 신호를 이용하여 휴먼보조 장치나 원격 제어에 활용할 수 있는 가상 로봇 팔 제어 방식을 제안한다. 4개의 표면 전극에서 근전도 신호를 측정하여 SOM과 LVQ를 이용하여 동작을 분류하는 시스템이다. 인터페이스 프로그램은 PC 상에서 구성하였다. 제안한 방식의 실험결과 94%의 분류 성공률을 얻었다.

• 한국융합학회논문지
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• 제10권12호
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• pp.183-189
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• 2019

본 연구의 목적은 근전도 바이오피드백 장비를 사용하여 움직임 조절운동을 수행할 때 엉덩관절 근육에 미치는 영향에 대해 알아보고자 하였다. 본 연구는 유사실험설계 단일집단 검사전-검사후 설계이다. 건강한 성인 21명이 본 연구에 참여하였다. 모든 대상자는 근전도 바이오피드백 장비를 사용하여 엉덩관절의 움직임 조절 운동을 총 20분간 수행하였다. 적은무릎 구부리기 검사 수행동안 엉덩관절의 근활성도 변화를 확인하기 위해 중간볼기근, 큰볼기근, 넙다리근막긴장근, 넙다리 곧은근의 활성도를 측정하였다. 본 연구 결과에서 중재 후 큰볼기근의 유의한 변화를 확인하였다. 이러한 결과는 근전도 바이오피드백 장비를 적용한 엉덩과절 움직임 조절운동이 엉덩관절의 안쪽돌림을 조절하고 엉덩관절 가쪽돌림근을 활성화시키는 효과적 중재방법임을 확인할 수 있었고, ICT 융합기술을 접목한 재활운동이 임상에서 효과적인 중재가 될 수 있음을 보여주었다.

• 한국전문물리치료학회지
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• 제19권1호
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• pp.37-45
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• 2012

The purpose of this study was to assess the influence of patellar height on quadriceps muscles' electromyography (EMG) activity during a squat exercise in adults with patella baja. For the study, we recruited 15 volunteers who had patella baja on the right side. We measured the EMG activity of the right rectus femoris, vastus medialis oblique, and vastus lateralis muscles during squat exercises under two conditions, specifically with and without an infra-patellar strap. The infra-patellar strap was applied below the tested patella to elevate the patella to a normal height. A paired t-test was used to compare the effects of patella height on EMG activity of the quadriceps muscles. The EMG activity of the rectus femoris (RF), vastus medialis oblique (VMO), and vastus lateralis (VL) muscles were significantly decreased during the squat exercise with the infra-patellar strap compared to the same exercise without the infra-patellar strap (p<.05), while the VMO/VL ratio was not different significantly between two conditions (p>.05). The findings of this study suggest that an infra-patellar strap may benefit people with patellar baja, as changes in patellar height could improve the efficiency of the quadriceps muscles.

• 한국전문물리치료학회지
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• 제18권1호
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• pp.47-56
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• 2011

The purpose of this study was to compare electromyography (EMG) activity for the middle and lower trapezius muscle according to various shoulder abduction angles. Thirty healthy male subjects were recruited for this study. Each subject performed three repetitions of horizontal abduction at $75^{\circ}$, $90^{\circ}$, $125^{\circ}$, $160^{\circ}$, and $180^{\circ}$ of shoulder abduction angle in a prone position. Surface EMG activity was recorded from the middle and lower trapezius while the subjects held for five seconds at a predetermined position. The EMG activity was normalized using the maximal voluntary isometric contraction (MVIC) elicited using a manual muscle testing technique. A repeatedly measured ANOVA was performed by Bonferroni's post hoc test. The EMG activity of the middle and lower trapezius was significantly different among shoulder abduction angles (p<.05). The greatest level of muscle activity for the middle and lower trapezius were demonstrated at $90^{\circ}$ and $160^{\circ}$ of shoulder abduction angle, respectively. These results suggest that middle and lower trapezius strengthening exercise and manual muscle testing should be performed at different shoulder abduction angles.

• 대한통합의학회지
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• 제10권4호
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• pp.137-143
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• 2022

Purpose : The purpose of this study was to evaluate the reliability analysis of the deep tendon reflex by using electromyography (EMG). Methods : The study was tested on 30 volunteers who are women in their 20s. Using an electronic reflective hammer of EMG, deep tendon reflex was measured on all subjects with the participation of three trained physical therapists as raters. First, the subjects were comfortably seated on a table with their knees bent at 90 °. The three raters tapped the electric hammer at intervals of 10 seconds to avoid habituation until a total of 10 compound muscle action potential records were collected. Intraclass correlation coefficients (ICCs) were calculated to assess the inter-rater reliability of the deep tendon reflex with the use of EMG. The items of analysis included amplitude (mV), latency (ms), duration (ms), and area (mV × ms) of the compound evoked potentials. Results : Based on the average records of 10 compound muscle action potential, excellent reliability (ICC: .912) was achieved in terms of area, and there was good reliability in terms of latency (ICC: .795) and duration (ICC: .800). In the shortest latency of the compound muscle action potential, good reliability was achieved in terms of amplitude (ICC: .865), duration (ICC: .781), and area (ICC: .832). In the amplitude of peak-to-peak of compound muscle action potential, excellent reliability was recorded in terms of amplitude (ICC: .924), and good reliability was recorded in terms of duration (ICC: .801) and area (ICC: .874). Conclusion : The findings in this study indicate that electromyography via an electric hammer is a reliable method of assessing and measuring deep tendon reflexes. Especially, it may be an excellent gauge in the area of average values of the compound muscle action potentials and the amplitude of peak-to-peak of compound muscle action potentials.

• 한국전문물리치료학회지
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• 제18권1호
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• pp.1-8
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• 2011

Push-up plus has been advocated for increasing the activity of the serratus anterior muscle, the most critical scapular stabilizer. However, no previous study has reported the possibility of compensatory motion on the part of the pectoralis major, which could substitute for the action of the serratus anterior during push-up plus. The aim of the current study was to investigate the immediate effect of electromyography (EMG) biofeedback of the pectoralis major muscle on the pectoralis major, upper trapezius, and serratus anterior muscles during push-up plus. Fourteen healthy young subjects voluntarily participated in this study; each subject performed push-up plus from the quadruped position, in two conditions (i.e., with or without visual and auditory biofeedback). Surface EMG was used to measure pectoralis major, serratus anterior, and upper trapezius activity. A paired t-test was used to determine any statistically significant difference between the two conditions. Additionally, effect size was calculated to quantify the magnitude of EMG biofeedback in each muscle. Visual and auditory feedback reduced pectoralis major muscle activity significantly (p=.000) and increased the serratus anterior muscle activity significantly (p=.002), but did not induce a significant difference in upper trapezius muscle activity (p=.881). Thus, it is concluded that the visual and auditory feedback of pectoralis major muscle activity can be used to facilitate serratus anterior muscle activity during push-up plus.