• 제목/요약/키워드: Maximal voluntary contraction

검색결과 143건 처리시간 0.027초

근피로에 의한 하지 대퇴직근의 경직도 분석을 위한 근전도 변화에 관한 연구 (A Study on the Electromyography Change for Analysis of rectus femoris muscle stiffness with muscle fatigues)

  • 이균정;남재현
    • 한국정보통신학회논문지
    • /
    • 제14권10호
    • /
    • pp.2317-2323
    • /
    • 2010
  • 근경직으로 인한 질병을 판단하기 위한 새로운 비침습적 초음파 근경직도 측정 시스템을 검증하기 위해 근경직 발생시 근전도의 변화를 분석하였다. 근경직 유발을 위해 하지 대퇴직근에서 등척성 운동을 실시하였다. 실험 프로토콜에 따라 실험을 반복 실시하였다. 이때 바이오시스템3를 이용하여 무릎관절토크의 크기 및 토크를 실시간으로 측정하였다. 또한 대퇴직근에서 근전도 측정 시스템으로 근전도를 측정하였다. 피검자는 실험 프로토콜에 따라 최초 무릎관절 토크의 최대수의적 등척성수축(MVC : maximal voluntary contraction)을 측정하고,. MVC의 50%에서 -5%로 떨어질때까지 등척성 운동을 지속하였다. 근경직 유발시 근전도 신호를 신호처리 과정을 거쳐 중앙주파수변동과 실효값 변화로 나타내었으며, 이러한 결과가 근경직도 측정 시스템의 결과와 유의함을 보였다.

복식호흡 운동이 요통환자의 체간근육 활성화에 미치는 영향 (Effect of diaphragmatic breathing exercise on Activation of trunk muscle of patients with low back pain)

  • 김경;박래준;배성수
    • The Journal of Korean Physical Therapy
    • /
    • 제17권3호
    • /
    • pp.311-327
    • /
    • 2005
  • The purpose of this study was to investigate the effects of diaphragmatic breathing on activation of trunk muscles of patients with low back pain. Diaphragmatic breathing may affect activation of trunk muscles. The assumptions are as follows: the crural diaphragm attatches to the lumbar vertebrae from L1 to L3, the voluntary downward pressurization of the diaphragm increases intra-abdominal pressure, and this increases the stiffness of the spine. Diaphragmatic breathing increases intra-abdominal pressure and the increased intra-abdominal pressure may contribute to the lumbar stability. Sixty patients with low back pain were randomly divided into two groups. Experimental group performed diaphragmatic breathing exercise with six breathing positions and control group performed only the breathing positions for five times per week during six weeks. % maximal voluntary contraction(% MVC) of trunk muscles on six breathing positions of experimental and control group was measured according to testing period of pre test, three weeks, and six weeks. The repeated measures of one-way ANOVA were used to analyze % MVC on trunk muscles of experimental and control group according to testing period. The results of this study were as follows: First, % MVC of right and left erector spinae in the right leg extension position indicated the statistically significant difference in experimental group which performed diaphragmatic breathing exercise rather than control group (p<0.05). Second, % MVC of right and left erector spinae in all-four positions indicated the statistically significant difference in experimental group which performed diaphragmatic breathing exercise rather than control group (p<0.05). Third, % MVC of right and left erector spinae, external oblique in the sitting position indicated the statistically significant difference in experimental group which performed diaphragmatic breathing exercise rather than control group (p<0.05). Fourth, % MVC of right and left erector spinae, external oblique in the standing position indicated the statistically significant difference in experimental group which performed diaphragmatic breathing exercise rather than control group (p<0.05). Fifth, % MVC of right and left erector spinae, external oblique in the supine position indicated the statistically significant difference in experimental group which performed diaphragmatic breathing exercise rather than control group (p<0.05). Sixth, % MVC of right and left erector spinae, external oblique in the lying on prone position indicated the statistically significant difference in experimental group which performed diaphragmatic breathing exercise rather than control group (p<0.05). In conclusion, as experimental group performed diaphragmatic breathing exercise according to the period of pre-test, post three weeks, and post six weeks, experimental group showed the greater significant effect on the activation of right, left erector spinae, and external oblique muscle. Diaphragmatic breathing exercise which resulted in activation of trunk muscles can be effective for managing the patients with back pain and should be utilized as the new therapeutic intervention.

  • PDF

경피신경전기자극이 근피로에 의한 자세균형과 근수축력의 변화에 미치는 효과 (Effectiveness of Transcutaneous Electrical Nerve Stimulation(TENS) on the Changes of Postural Balance and Muscle Contraction following Muscle Fatigue)

  • 조휘영;이순현;인태성;강선희;이동엽;송창호
    • 한국산학기술학회논문지
    • /
    • 제11권11호
    • /
    • pp.4418-4426
    • /
    • 2010
  • 근피로는 자세균형과 근수축력의 악화를 유발하여 다양한 근골격계 손상을 초래한다. 본 연구는 하퇴삼두근에 근피로 유발에 의한 자세불균형과 근수축력 저하에 경피신경전기자극이 미치는 효과를 알아보고자 하였다. 2010년 3월부터 4개월간 전정계통과 시각계통에 문제가 없는 20명의 건강한 성인을 대상으로 반복운동 수행을 통하여 비복근에 근피로를 유발하였고, 유발 후 즉시 경피신경전기자극을 적용하였다. 근피로 및 경피신경전기자극에 의한 자세균형과 근수축력의 변화를 측정하기 위하여 자세동요 이동거리와 속도, 최대수의수축력을 사용하였다. 근피로 유발에 의하여 자세동요 이동거리 및 속도의 증가와 근수축력의 저하가 나타났다(p<.05). 근피로가 유발된 비복근에 경피신경 전기자극의 적용은 근피로에 의한 자세동요와 근수축력을 유의하게 개선하였다(p<.05). 이와 같은 연구결과를 통하여 족저굴곡근의 근피로는 자세균형과 근수축력에 관여되고, 경피신경전기자극은 근피로에 의한 자세불균형 및 근수축력 저하에 효과적임을 증명하였다. 경피신경전기자극은 일상생활에서 흔히 유발되는 근피로의 중재에 경피신경전기자극이 효과적인 중재 방법으로 사용될 수 있을 것으로 사료된다.

근전도의 정량적 분석시 사용되는 수리적 파라미터의 민감도 비교 (The Comparison of Sensitivity of Numerical Parameters for Quantification of Electromyographic (EMG) Signal)

  • 김정룡;정명철
    • 대한산업공학회지
    • /
    • 제25권3호
    • /
    • pp.330-335
    • /
    • 1999
  • The goal of the study is to determine the most sensitive parameter to represent the degree of muscle force and fatigue. Various numerical parameters such as the first coefficient of Autoregressive (AR) Model, Root Mean Square (RMS), Zero Crossing Rate (ZCR), Mean Power Frequency (MPF), Median Frequency (MF) were tested in this study. Ten healthy male subjects participated in the experiment. They were asked to extend their trunk by using the right and left erector spinae muscles during a sustained isometric contraction for twenty seconds. The force levels were 15%, 30%, 45%, 60%, and 75% of Maximal Voluntary Contraction (MVC), and the order of trials was randomized. The results showed that RMS was the best parameter to measure the force level of the muscle, and that the first coefficient of AR model was relatively sensitive parameter for the fatigue measurement at less than 60% MVC condition. At the 75% MVC, however, both MPF and the first coefficient of AR Model showed the best performance in quantification of muscle fatigue. Therefore, the sensitivity of measurement can be improved by properly selecting the parameter based upon the level of force during a sustained isometric condition.

  • PDF

악력 세기와 뇌파의 상관관계에 관한 연구 (Study on the Correlation between Grip Strength and EEG)

  • 김동은;박승민;심귀보
    • 제어로봇시스템학회논문지
    • /
    • 제19권9호
    • /
    • pp.853-859
    • /
    • 2013
  • The purpose of this study was to identify the correlation between electroencephalography (EEG) and strength, using grip strength. 64-channel EEG data were recorded from five healthy subjects in tasks requiring handgrip contractions of nine levels of MVC (Maximal Voluntary Contraction). We found the ERS (Event-Related Synchronization)/ERD (Event-Related Desynchronization) at the measured EEG data using STFT (Short-Time Furier Transform) and spectral power in the EEG of each frequency range displayed in the graph. In this paper, we identified that the stronger we contracted, the greater the spectral power was increased in the ${\beta}$, ${\gamma}$ wave.

골격근에서 최대 수의적 등척성 수축력과 근 두께와의 관계 (Maximal Voluntary Contraction and Muscle Thickness Relationship in Skeletal Muscle)

  • 정진규;김양호;김태열
    • 대한임상전기생리학회지
    • /
    • 제2권2호
    • /
    • pp.25-37
    • /
    • 2004
  • To provide reflection diagnostical basic-data by ultrasonography intended for 38 male/female students used by ultrasound imaging system and dynamometer, compared the MVIC and muscle thickness take an accurate measurement of elbow flexor and knee extensor of thickness and MVIC, in confirmity with distinction of sex and then analysised of correlation in muscle thickness-MVIC, MVIC-weight, weight-muscle thickness, it shows statiscally significant difference MVIC and muscle thickness according to sex. Also there is a high interrelation between two. As well as it shows that there is a different between sex in the MVIC of same thickness and MVIC of same weight. This difference will be related with preportions of muscle fiber type in view of the results by preceded research, it needs to be prerequisite analysis of difference in sex with a great variety of ways hereafter.

  • PDF

sEMG 분석을 이용한 높이 들어올리기 자세에서의 신체적 작업부하의 정량적 평가방법 개발 (Evaluation Method of Physical Workload in Overhead Lifting Posture Using Surface EMG Analysis)

  • 이영진;지영준
    • 대한의용생체공학회:의공학회지
    • /
    • 제32권4호
    • /
    • pp.328-335
    • /
    • 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.

만성요통환자의 한발서기 시 체간 안정화 근육의 활성화 변화 (Trunk Stabilization Muscle Activity in Chronic Low Back Pain Patients during One Leg Stance)

  • 민동기
    • 대한물리치료과학회지
    • /
    • 제21권1호
    • /
    • pp.13-20
    • /
    • 2014
  • Purpose : The purpose of this study was to analyze and compare the surface electromyography(EMG) activity of trunk region muscle between normal subjects and chronic low back pain(CLBP) patients during one leg stance. Methods : The subjects were 27 people, were consisted of 12 subjects who don't have low back pain and 15 subjects who have low back pain from 19 to 28 year of age(mean age 22.22). We used surface EMG to evaluate the activity of the Rectus abdominis, External abdominal oblique, Quadratus lumborum, Gluteus medius muscle. We used independent two samples t-test for statistical data. Results : The result of this study showed that the maximal voluntary isometric contraction(%MVIC) ratio of the trunk muscles was higher in patients with CLBP than in normal subject. But there were no statistically significant differences. There were statistically significant differences of the activity of the Quadratus lumborum, Gluteus medius muscle(p<0.05).

  • PDF

시간경과에 따른 지연성근통증 내측 비복근의 초음파 영상 (Medial Gastrocnemius Ultrasound Imaging of Delayed Onset Muscle Soreness over time)

  • 이완희;조기훈;이경숙;김미화
    • 한국산학기술학회논문지
    • /
    • 제13권6호
    • /
    • pp.2632-2640
    • /
    • 2012
  • 본 연구의 목적은 지연성근통증에 대한 내측 비복근 초음파 영상의 측정도구로서의 가능성에 대해 알아보고자 함에 있다. 본 연구는 2011년 4월 21일부터 4월30일까지 실시되었다. 평소 규칙적인 운동을 하지 않으며, 최근 외상의 경험, 근골격계 질환, 심혈관계 질환이 없고 약물을 복용하지 않는 35명의 건강한 성인이 참여하였다. 대상자들은 5시간의 등반을 통해 지연성근통증을 유발하였으며, 지연성근통증 전과 지연성근통증 후 24, 48, 72시에 통증(visual analogue scale :VAS), 혈중 크레아틴 키나아제(creatine kinase: CK) 활성도, 족저 굴곡근의 최대근수축력(maximal voluntary isometric contraction: MVlC)을 측정하였고, 이 측정값과 초음파로 측정한 내측 비복근의 우상각을 비교하였다. 연구의 결과는 다음과 같다. 통증지표, 혈중 크레아틴 키나아제 활성도, 족저 굴곡근 최대등척성근수축력에 측정시기에 따른 유의한 차이가 발생하였으며(p<0.05), 내측 비복근 우상각에서도 측정시기에 따른 유의한 차이가 발생하였다(p<0.05). 또한 변수 간 측정시기에 따른 변화의 흐름이 일치하는 것을 확인하였다. 본 연구를 통해 초음파 검사를 통한 내측 비복근 우상각의 시간경과에 따른 변화 측정이 지연성근통증을 감지하는 새로운 측정방법으로 사용될 수 있을 것이라 생각한다.

무릎넙다리통증증후군 환자에서 무릎관절 각도별 스쿼트 융합운동이 넙다리네갈래근의 근력에 미치는 효과 (A Effect of the Squat Convergence Exercise Among Knee Joint Angle on Quadricpes Strength in the Patients With Patellofemoral Pain Syndrome)

  • 조상희;이수영
    • 한국융합학회논문지
    • /
    • 제7권2호
    • /
    • pp.43-52
    • /
    • 2016
  • 본 연구의 목적은 넙다리네갈래근 중 안쪽빗넓은근과 가쪽넓은근의 강화를 위해 효과적인 스쿼트 운동자세를 제시하는 데 있다. 연구대상자는 무릎넙다리통증증후군이 있는 20명의 환자로 본 연구에 자발적으로 참여하였다. 대상자들은 무릎관절 굽힘 각도 $45^{\circ}$, $60^{\circ}$, $90^{\circ}$ 자세에서 정적인 스쿼트 융합운동을 30초 동안 총 5회 실시하였다. 측정변수는 넙다리네갈래근의 최대 수의적 등척성 수축력(MVIC), 넙다리네갈래근 각(Q 각)과 넙다리 둘레이며, 무릎관절 자세에 따라 스쿼트 운동 전후로 측정되었으며 그 변화률을 통계분석에 사용하였다. 연구결과 넙다리네갈래근의 무릎관절 각도별 MVIC 변화율은 $90^{\circ}$ 무릎관절 굽힘에서 유의하게 증가하였으나(p<.05), Q 각과 넙다리 둘레의 변화율엔 유의한 차이가 없었다(p>.05). 따라서 무릎통증증후군 환자의 넙다리네갈래근의 강화를 위해서 무릎관절 $90^{\circ}$ 굽힘된 스쿼트 자세가 효과적임을 제시한다.