• Physical Therapy Korea
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• v.5 no.4
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• pp.9-19
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• 1998

연구목적 이 연구의 목적은 피로유발수축후 장딴지근과 가자미근의 근전도 power spectrum 중앙경항치를 비교 검사하는 것이다. 실험대상 열 여섯명의 자원자(남자 10, 여자 6)를 대상으로 하였다. 남자 대상자의 연령범위는 25세에서 33세(평균 $28.6{\pm}2.5$)였고 여자 대상자의 연령범위는 26세에서 31세($27.8{\pm}1.9$)였다. 실험방법 실험대상자는 피로유발수축전후 50% 최대등척성근수축을 수행하였다. 자료수집과 분석을 위해 LabVIEW 소프트웨어를 사용하였다. 결과 t-검정결과 내측 장딴지근에서는 피로유발수축후 주파수의 중위값과 평균이 통계적으로 유의하게 감소하였으나 가자미근에서는 통계적으로 유의한 차이가 없었다. t-검정결과 두 근육간 주파수 감소의 차이는 통계적으로 유의한 차이가 있었다. 토의 및 결론 이 결과들은 피로유발수축후 근전도 power spectrum 중앙경향치가 저주파대역으로 감소함을 나타내었다. 이 연구는 중앙주파수와 평균주파수가 피로지수로서의 신뢰도와 타당도가 뛰어나며 객관적 측정과 훈련효과 평가로 사용할수 있음을 보였다.

• Physical Therapy Korea
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• v.10 no.4
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• pp.61-68
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• 2003

본 연구의 목적은 운동강도(최대근수축의 10, 30, 50, 70%)에 따라 유발되는 국소적인 근피로가 슬관절의 위치감각 인지에 미치는 영향을 연구함으로써 근력강화의 운동치료적 효과와 운동학습과 관련된 효과를 동시에 만족시키는 최적의 운동강도를 제시하는 것이었다. 대상자는 건강한 성인여자 40명이었다. 청각을 통한 위치감각 정보를 제공하는 장치와 원판 각도계가 부착된 등속성 Cybex를 사용하였다. 근피로의 상태를 확인하기 위해서 근전도를 이용하여 주파수 스펙트럼 분석을 실시하였다. 청각되먹임이 주어진 각도와 대상자에 의해 재생되어진 각도의 오차값들과 근피로의 변화를 비교하기 위해 일요인 분산분석을 이용하였다. 오차값들의 평균은 50%의 군에서 가장 작았으며 근피로 또한 70%의 군에서만 크게 생성되었다. 따라서 최대 근 수축력의 50%가 운동치료 시 가장 효과적인 운동강도임을 알 수 있었다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.11
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• pp.4418-4426
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• 2010

Muscle fatigue often induces deterioration of postural balance and muscle contraction, such as strength or maximal voluntary contraction(MVC). This study was to investigate the effects of transcutaneous electrical stimulation(TENS) applied to the fatigued muscles on postural imbalance and decline in muscle strength following fatigue of triceps surae. For the 4 months from March, 2010, twenty healthy subjects without vestibular disease and visual disturbance were recruited and induced muscle fatigue of triceps surea performed by repeated voluntary contraction. TENS was applied to gastocnemius immediately after development of muscle fatigue. Postural sway length, velocity and MVC were recorded under these conditions: pre-fatigue, post-fatigue, and TENS application to fatigued muscle during post-fatigue. Muscle fatigue increased postural imbalance as expressed by sway length and velocity and decreased muscle contraction(p<.05), while TENS improved the postural imbalance and MVC following muscle fatigue during stance(p<.05). The results suggested that fatigue on plantar flexor is associated with postural balance and muscle contraction, and TENS application to fatigued muscle was effective in improving postural imbalance and decline in muscle strength following muscle fatigue. TENS will be an effective method in exercise, working environment and daily life.

• Proceedings of the Safety Management and Science Conference
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• 2012.11a
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• pp.393-401
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• 2012

본 연구에서의 미용업 종사자의 감정노동, 직무 및 사회심리적 스트레스, 피로도가 근골격계질환에 미치는 직 간접적인 영향을 평가하기 위하여 시도되었다. 그 결과 미용업 종사자의 근골격계질환 자각증사자는 신체부위 중 어깨의 근골격계질환 관련 자각증상자가 가장 많았으며, 목, 허리, 손목, 팔, 발, 무릎 순으로 나타났다. 미용업 종사자의 감정노동 각 문항별 평가 결과는 '나는 기분이 나쁠 때 고객들에게 표현하지 않도록 최선을 다한다'의 문항이 3.92점으로 가장 높게 나타났으며, 이와 반대로 '표현되는 행동과 실제 감정의 차이 때문에 혼란스러울 때가 있다' 2.61점으로 나타났다. 미용업 종사자의 작업 관련 심리적인 요인이 근골격계질환에 미치는 영향에 대하여 근골격계질환자가 무증상자에 비하여 감정노동과 피로도에 영향을 더 많이 받는다는 것으로 나타났으며, 직무 스트레스가 증가할수록 사회심리적 스트레스는 낮아지지만 피로도가 증가하는 것으로 나타났다. 감정노동이 피로도에 미치는 영향에서 직 간접적인 영향이 모두 높은 것으로 나타났으며 직무 스트레스가 피로도를 통해 근골격계질환에 미치는 간접적인 영향이 큰 것으로 나타났다. 본 연구를 통하여 미용 종사자의 작업 관련 물리적 심리적 개선 방안 마련이 요구되면 산업안전보건 분야의 정책적 관리 방안 마련을 제안한다.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.6 no.1
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• pp.59-65
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• 2012

In this study, muscle fatigue of biceps and triceps during isometric exercise depending on concentric contraction and eccentric contraction was evaluated using EMG. 12 healthy male volunteers was performed concentric exercise and eccentric exercise by maximum flection and extension of elbow joint. Integrated EMG (IEMG) in time domain and mean power frequency (MNF) in frequency domain were calculated. MNF of the biceps and triceps was decreased, whereas IEMG was increased during concentric contraction and eccentric contraction. But muscle fatigue index appeared higher at region of stretched muscle length. in this result, muscle fatigue occurs at both biceps and triceps muscle during concentric and eccentric exercise, and muscle fatigue was affected by muscle contraction and extension.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.1
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• pp.351-359
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• 2017

This study examined emotional labor, fatigue, and musculoskeletal pain in hospital nurses. The study sample included 235 hospital nurses. The data were collected by questionnaire and analyzed with descriptive statistics, t-test, ANOVA, Scheffe test, Pearson's correlation coefficients, and multiple regression.The average emotional labor score was 3.27, and of fatigue was 2.04. The musculoskeletal pain score was 4.43. Emotional labor and fatigue are significantly positively associated with musculoskeletal pain(r=.180, p=.006; r=.278, p<.001). Emotional labor was positively associated with the degree of fatigue(r=.353, p<.001). The significant predictors of musculoskeletal pain for nurses were physical fatigue(${\beta}=.324$, p<.001) and gender(female)(${\beta}=.171$, p=.009), explaining 13.7% of the variance in musculoskeletal pain(F=16.271, p<.001). The results suggest that engaging in emotional labor related to nursing tasks increases the risks of fatigue and musculoskeletal pain. Therefore, it is important to develop a management program to relieve the emotional labor, fatigue, and prevent musculoskeletal pain for clinical nurses.

• Journal of Life Science
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• v.20 no.6
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• pp.870-876
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• 2010

The purpose of this study was to examine the effect of kinesio taping on muscle strength and changes of muscle fatigue and damage. 10 male subjects participated in 1-RM and isometric cybex muscle strength tests with and without taping application. Muscle strength (bench press, leg press) and extension (knee, shoulder) strength were significantly increased after taping, but there was no significant difference in flexion (knee, shoulder) strength. The concentration of fatigue factors (ammonia, phosphorous), muscle damage index substances (CK, LDH), IGF-I and creatinine were reduced after taping, but there were no significant differences.

• Proceedings of the KAIS Fall Conference
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• 2009.12a
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• pp.1010-1013
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• 2009

In this paper we propose the measurement of muscle fatigue using STFT(short time fourier transfom). The proposed method is time-frequency representation of muscle activity. We suggest that the proposed method can replace the classical muscle fatigue monitoring method using the median frequency.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.5
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• pp.1231-1239
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• 2010

The aim of this study was developing the non-invasive focused magnetic stimulation system(NI_FMSS) that can stimulates acupoints which are small parts and knotted muscular tissues. To evaluate pain treatment effect of the NI_FMSS, we caused muscle fatigue to 25 subjects in biceps of the arm. Then, we stimulated acupoints(trigger points) HT2 using low frequency stimulator(10 subjects) and NI_FMSS(10 subjects). The other 5 subjects had not been stimulated. We analyzed muscle fatigue recovery with median frequency, RMS and median power in frequency domain for 5 days. We checked the magnetic stimulation effect on acupoint by evaluation of muscle fatigue recovery. Therefore, we identified that the NI_FMSS was more efficient system to relieve muscle pain than electric-stimulation system.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.2 no.1
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• pp.17-22
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• 2009

In this paper, we extract well-known parameters such as zero crossing rate(ZCR), low band energy(Band) and median frequency(MDF) from surface electromyogram (EMG), and compare to evaluate themselves as measures for fatigue. In experiments, 3 males and 3 females volunteered to participate in surface EMG recordings placed on the biceps brachii and each recording experiment continued until exhaustion.