We assessed whether the use of a symmetrical upper limb motion trainer in daily repetitive training for a 6-week period reduced spasticity and improved motor function in three chronic hemiparetic patients. Upper limb motor impairment and disability were measured by the Fugl-Meyer Assessment (FMA), Modified Ashworth Scale (MAS) and Manual Muscle Test (MMT), respectively. The electromyography (EMG) of the affected hand was recorded during isometric wrist flexion and extension. In all patients, FMA and MMT scores were significantly improved after the 6-week training. However, MAS scores of the affected wrist spasticity did not change considerably. Onset and Offset delays in muscle contraction significantly decreased in the affected wrist. The co-contraction ratio of flexor and extensor muscles significantly increased after the 6-week training. Onset and offset delays of the muscle contraction and co-contraction ratio correlated significantly with the patients' FMA. This study showed that repetitive, symmetric movement training can improve upper limb motor functions and abilities in chronic hemiparetic patients. Also, the EMG assessment of motor response is likely to provide insights into mechanisms and treatment strategies for motor recovery in chronic hemiparetic patients.

To compare the effects of forward walking and backward walking on surface electromyographic analysis of quadriceps muscles at treadmill grades of 0%, 5% and 10%, subjects were randomized to eleven athletics (5 females, 6 males), with a mean age of 17.8 years, and a SD of 4.66 years. The values of the surface electromyographic (SEMG) activity of the rectus femoris (RF), vastus lateralis (VL) and vastus medialis oblique (VMO) were measured during forward walking and backward walking on a treadmill at grades of 0, 5 and 10%. The subjects walked for approximately 10 seconds at 4.0 km/h. The data were analyzed by repeated measuring of the two-way ANOVA and analyzed by a paired t-test between forward walking and backward walking. The SEMG activity levels of the RF, VL and VMO were the highest when both the forward walking and backward walking increased incrementally for treadmill grades of 0% to 10%, but the VMO/VL ratio had no significant changes. The SEMG activity levels of the RF, VL and VMO were significantly different between directions. However, SEMG activity levels of the RF, VL, VMO and VMO/VL ratio did not show significant difference among the treadmill grades. No statistically significant interactions were detected between the direction of walking and treadmill grade. Backward walking on the treadmill at 4 km/h and grades of 0%, 5%, 10% elicited a greater SEMG activity on the quadriceps muscles than did forward walking under the same conditions. The results suggest that the quadriceps may be effectively activated by performance at treadmill grades of 10%. This investigation confirms that backward walking up an incline may place additional muscular demands on individuals.

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 주파

보행 종료(gait termination)는 인간의 보행개시(gait initiation)나 율동성 보행(rhythmical walking)에 비해 관심을 적게 받고 있다. 파킨슨 환자들이 보행종료와 방향전환 시 가지는 어려움은 이들 환자들이 보행 시 넘어지게 되는 노출 요인으로 보고되어져 왔다. 보행종료에 대한 기전의 이해는 효과적으로 걸음을 멈추지 못해 넘어지게 되는 위험요인을 가진 사람들에게 적용되어질 수 있다. 이 논문에서 우리는 보행종료에 대한

본 연구는 상지운동 동안에 복부에 적용된 압력이 요부와 복부의 근피로도에 미치는 영향을 알아보았다. 연구대상자는 성인 남자 5명이었다. 연구대상자가 10 repetitions maximun (RM) 무게의 아령을 이용하여 1분 동안 상지운동을 수행 시 0 mmHg, 저압(30 mmHg), 중압(70 mmHg), 고압(100 mmHg)의 외부 압력이 복부에 적용되었고, 복직근, 외복사근, 내복사근, 척추기립근에서 근전도 자료가 수집되었다. 주파수 분석을

The purpose of this study was to analyze the effects of three different pelvic tilts on sit-to-stand ativities and to suggest a new therapeutic approach for movement reeducation in patients who have difficulty with sit-to-stand activities. The three different pelvic tilts were: (1) comfortable pelvic tilt sit-to-stand (CPT STS), (2) posterior pelvic tilt sit-to-stand (PPT STS) and (3) anterior pelvic tilt sit-to-stand (APT STS). To analyze the kinematic component of STS, a motion analysis system (Zebris) was applied to the ankle, knee, hip joint, and thigh-off area. Also, to determine the onset time of muscle contraction, surface electrodes were placed to the rectus femoris muscle (RF), the vastus lateralis muscle (VL), the biceps femoris muscle (BF), the tibialis anterior muscle (TA), the gastrocnemius muscle (GCM), and the soleus muscle (SOL). One-way repeated ANOVA was used for the statistical analysis. First, significant differences were found in kinematic variables for the hip, knee, ankle joint, and thigh-off among the three activities. Second, there was significant difference in muscle activation pattern in TA. VL. and BF among three activities. In conclusion, the findings of this study suggest the following evaluative and therapeutic approach for STS activity: (1) Changes in knee and ankle joints should be prioritized and recruitment order differences in VL and RF can be generated to accomplish abnormal STS activity. (2) APT STS can be introduced for movement efficiency and functional advantage when abnormal STS is treated.

본 연구에서는 스포츠웨어용 나일론 직물 소리가 심한 소음으로 인해 불쾌감을 주므로 이를 감소시키기 위한 방안으로, 5개의 나일론 직물소리를 녹음하여 이를 피험자에게 들려주면서 EMG와 주관적 감각을 측정함으로써, 직물소음이 근전도와 주관적 감각에 미치는 영향을 고찰하였다. 근전도는 상완이두근과 전완근에서 측정하였고, 주관적 평가는 자유식 크기평가법(Free Modulus Magnitude Estimation)을 이용하였다. 직물 소리에 대한 상완이두근의 근전도 값은 전완근의 근전도값보다 컸으며, 소리자극 유무시의 차이값도 상완이두근에서 크게 나타났다. 직물의 소리가 부드럽고 유쾌할수록 근전도값은 무자극시보다 감소하는 경향을 보였으나, 직물의 소리가 시끄럽고 날카로울수록 근전도값은 무자극시보다 증가하였다. 직물의 소리는 상완이두근의 근전도 값에 영향을 미쳐, 직물 소음의 크기, 날카로움 등과 정적인 관계를 보이는 것을 볼 수 있었다. 직물소리의 물리적 특성과 근전도로부터 나일론 직물 소리에 대한 감각ㆍ감성 예측식에서는 높은 예측력을 보였다. 맑고, 거칠고, 높은 소리감각을 제외한 예측식에서 소리특성 외에 생리신호인 근전도 가 포함되어 직물소리 감성을 예측하는 의미있는 파라미터임을 알 수 있었다.

This study tested whether repeated measurement of median frequency (MDF)-related variables could express the muscle power changes during a 12-week DeLome strengthening program, by using consecutive overlapping FFT (Fast Fourier transformation) and integrated EMG (IEMG) from surface EMG data for isometric and isotonic exercise. To evaluate the effect of training, the following were recorded every 3 weeks for the elbow flexors and knee extensors of 5 healthy male volunteers: MVC, lRM, limb circumference, and surface EMG during isometric MVC or isotonic contraction at 10RM load. From the EMG data, IEMG and variables from a regression analysis between MDF and time were obtained. MVC, lRM, IEMG, and initial MDF increased linearly over the training period. The fatigue index and slope of the regression line increased temporarily until the 6th week and decreased thereafter. From these results, there appeared to be enhanced neural recruitment of fast twitch fibers in the first 6 weeks and continued enhancement in the recruitment and hypertrophy of fast twitch fibers, which led to increased fatigue resistance, over the last 6 weeks. Accordingly, the MDF and IEMG analysis technique could demonstrate the effect of the program detected significant changes in both isometric and isotonic contractions. EMG analysis methods can be used to estimate the electrophysiological and histological changes in skeletal muscles during a strengthening program.

The purpose of this study was to compare the relative accuracy of a range of computer-based analysis with respect to EMG onset determined visually by an experienced examiner. Ten healthy students (6 male, 4 female) were recruited and three times randomly selected trials of isometric contraction of wrist flexion and extension were evaluated using four technique. These methods were compared which varied in terms of EMG processing, threshold value and the number of samples for which the mean must exceed the defined threshold, and beyond 7% of maximum amplitude. To identify determination of onset time, ICCs(Intraclass Correlation Coefficients) was used and inter-rater arid intra-rater reliability ranged good in visually derived onset values. The results of this study present that in wrist flexion and extension, the reliability of the inter and intra-examiner muscle contraction onset times through visual analysis showed beyond .971 with ICCs. The reliability of the muscle contraction onset time decision through visual reading, tested with computer analysis, showed a relationship of all the selected analysis methods with ICCs .859 and .871. The objective computer-based analysis comparing with visual reading at the same time is the effective and qualitative data analysis method, considering the specificity of each study method.

The purpose of this study was to determine EMG biofeedback training effect on the muscle activities in 3 unilateral facial palsy patients along with multiple baseline design across subjects. The auditory feedback about facial muscles (orbicularis oris, orbicularis oculi, frontalis) was provided with each patient during facial exercise training. Electromyographic (EMG) activity during maximal voluntary contraction and maximal compound muscle action potential (CMAP) amplitude elected by supramaximal electrical stimulation on facial nerve of facial muscles were measured pre- and post- EMG biofeedback training to evaluate motor learning. EMG activity during maximal voluntary contraction was increased after EMG biofeedback training and CMAP amplitude elected by supramaximal electrical stimulation was not changed in all subjects. The results indicate that EMG biofeedback training is useful method to improve motor learning of facial excercise training in unilateral facial palsy patients.

본 연구는 보행주기 동안 정상인과 당뇨병성 족부궤양 환자의 족관절 운동역학적 변수와 족관절 근육들의 근활성도에 차이가 있는지 알아보기 위하여 실시하였다. 본 연구의 대상자는 당뇨병성 족부궤양이 있는 환자 9명(남자: 6명, 여자: 3명)과 성, 연령, 체중으로 짝짓기(matching)시킨 대조군 9명이었다. 3차원 동작분석기, 힘판, 표면 근전도를 이용하여, 보행주기 동안 족관절의 관절가동범위, 모멘트(moment), 일률(power), 그리고 내측가자

19명의 건강한 성인 남자의 우세팔쪽 위팔두갈래근에서 피로가 생길 때까지 2.4초를 하나의 주기로 팔꿉을 반복적 등장성으로 굽히고 펴서 표면근전도 신호를 얻었다. 처리과정 A 중앙주파수(MDF )는 이 신호의 0.5초 구간을 power spectrum analy sis (PSA)로 계산하였는데 상당량의 잡음이 있었다. 중앙주파수의 잡음 양을 비교하기 위해, 동일한 표면근전도에서 3번까지 신호를 받았다 (2.4초 구간을 PSA로 계산한 처리과정 B, 13 point로 moving averages한 처리과정 C, digital low pass filter한 처리과정 D). 그리고 나서 그 신호의 중요 주파수 성분을 뽑아내었다. 위의 중앙주파수 자료와 시간간의 회귀직선을 분석하면 초기 중앙주파수, 회귀기울기, 그리고 피로지수와 같은 모수를 얻을 수 있다. 비모수 검정의 하나인 Kendall 기법으로 네 개의 처리과정간의 모수를 비교하였다. 통계결과 잡음이 처리과정 A보다 B,C,D에서 적었고, D에서 가장 적게 나타났다. 중앙주파수를 digital low pass 로 여과(filtering)함으로써 앞으로 있게 될 동적 운동 시 근피로 모니터기의 신뢰도를 높일 수 있다.

Many studies have shown that the initial median frequency (MDF) and slope correlate with the muscle fiber composition. This study tested the hypothesis that the initial MDF and slope are fixed, regardless of the interval at which data are collected. MDF data using moving fast Fourier transformation of EMG signals, following local fatigue induced by isotonic exercise, were obtained. An inverse FFT was used to eliminate noise, and characteristic decreasing regression lines were obtained. The regression analysis was done in three different periods, the first one third, first half, and full period, looking at variance in the initial MDF, slope, and fatigue index. Data from surface EMG signals during fatiguing isotonic exercise of the biceps brachii and vastus lateralis in 20 normal subjects were collected. The loads tested were 30% and 60% maximum voluntary contraction (MVC) in the biceps brachii and 40% and 80% MVC in the vastus lateralis. The rate was 25 flexions per minute. There were no significant differences in the initial MDF or slope during the early or full periods of the regression, but there was a significant difference in the fatigue index. Therefore, to observe the change in the initial MDF and slope of the MDF regression line during isotonic exercise, this study suggest that only the early interval need to be observed.

In rehabilitation programs involving muscle re-education and endurance exercise, it is necessary to confirm when fatigue occurs. It is also necessary to quantify fatigue, to confirm whether the muscle has been exercised sufficiently. In general, as fatigue occurs, the force-generating ability of the muscle is reduced. If the median frequency (MDF) obtained from electromyogram (EMG) power spectrum is correlated highly with work, then the timing and degree of fatigue may be confirmed. This study examined the relationship between work and MDF obtained from the EMG power spectrum during repetitive isokinetic exercise. Surface EMG signals were collected from biceps brachii and vastus lateralis of 52 normal subjects (26 males, 26 females) at and while performing an isokinetic exercise. The exercise was finished at 25% of peak work. MDF data was obtained using a moving fast Fourier transformation (FFT), and random noise was removed using the inverse FFT, then a new MDF data was obtained from the main signal. There was a high correlation between work and MDF during repetitiv isokinetic exercise in the biceps brachii and vastus lateralis of males and the biceps brachii of females (r=.50~.77). However, there was a low correlation between work and MDF in the vastus lateralis of females (r=.06~.19).

This study was designed to identify the effects of foot position on electromyographic (EMG) activity of the quadriceps femoris during maximum voluntary contraction (MVC) in standing. Twenty young adults who had not experienced any knee injuries were recruited. Their Q-angles were within a normal range. They were asked to stand in five different foot positions ( externally rotated, internally rotated, neutral, plantarflexed, and dorsiflexed foot position). The EMG activities of the vastus lateralis (VL), rectus femoris (RF), and vastus medialis oblique (VMO) were recorded in standing by surface electrodes and normalized by MVC EMG values derived from manual muscle test. The normalized EMG activity levels (%MVC EMG) of muscles in the five foot positions were compared using repeated measures ANOVA. The EMG activity levels of the VL, RF, and VMO were the highest when foot was externally rotated. The EMG activity levels of the VL and RF were significantly different among the foot positions (p<.05). However, EMG activity levels of the VL, RF, VMO, and VMO/VL ratio did not show significant differences in each foot position (p> .05). The results suggest that the quadriceps femoris may be effectively activated by performing MVC at an externally rotated foot position. Therefore, the externally rotated foot position can be considered as an effective foot position for quadriceps femoris strengthening exercise. Further studies are needed to identify whether there are differences in the effects of foot position on muscle strength after MVC exercise of quadriceps femoris in standing.

본 연구의 목적은 운동제어/학습 또는 운동역학을 연구하는데 중요한 역할을 하는 근전도의 사용과 근전도와 등척성 수축력과의 관계에 나타나는 문제점과 제안점을 조사하는 것이다. 선행연구를 분석한 결과, 등척성 힘의 증가에 따른 근전도의 증가 관계가 선형적 모양으로 나타나지는 않았다. 또한, 선행연구에서 근전도와 등척성 힘 관계를 연구하는데 몇 가지 문제점들이 발견되었다. 이러한 문제점은 선행 연구실험들의 절차상에 차이가 나타났고, 근육의 생리학적인 또는 해

MMH(Manual Material Handling)와 관련되어 최근 요통질환으로 인한 요양신청이 크게 증가하는 추세에 있다. 본 연구에서는 Lifting 작업시 적용되는 중요 요소들 중 수평거리가 변함에 따른 IEMG 값을 이용하여 EMG 변화를 살펴보았다. 좌ㆍ우 EMG 값간에는 유의한 차이가 없었으며, 수평거리 35cm와 55cm간에는 유의한 차이를 보였다. 이는 수평거리가 길어질 경우 척추기립근의 동원량이 증가한다는 것을 의미한다. 따라서 요추부의 부담도를 줄이기 위해 수평거리를 줄이는 것이 요통예방을 위해 무엇보다 중요한 것이라 하겠다. 인체측정치와 EMG 값 사이의 상관관계에서는 35cm일 때 키, 가슴둘레, 허리둘레 등이, 55cm일 때 체중, 몸통너비, 허리두께, 손바닥폭 등이 상관관계가 있는 것으로 나타나고 있다.

The purpose of this study was to assess the fatigue in lumbar and abdominal muscles in patients with chronic low back pain compared with normal subjects using spectral analysis with mean power frequency and median power frequency. The experimental group consisted of twenty subjects who had experienced chronic low back pain for over one year after the onset day. A control group consisted of twenty normal subjects with no history of low back pain. All subjects stood in an apparatus to perform sustained contraction in the lumbar and abdominal muscles for 30 seconds with 60% maximal voluntary isometric contraction (MVIC). The resulting electromyographic (EMG) recorded time serial data were transformed into frequency serial data by Fast Fourier Transformation (FFT). The results were as follows: 1) lumbar muscles measured, the frequency change ratio of both median power frequency and mean power frequency was significantly greater for experimental group compared with control group group (p<0.05). In measured two abdominal muscles (inferior rectus abdominis, obliquus externus abdominis) except superior rectus abdominis, the frequency change ratio of both median power frequency and mean power frequency was significantly greater for experimental group compared with control group (p<0.05). 2) In all three (longissimus thoracis, iliocostalis lumborum, multifidus) lumbar muscles measured, the initial frequency value of both median power frequency and mean power frequency was significantly lower for the experimental group compared with the control group (p<0.05). In the two (inferior rectus abdominis, obliquus externus abdominis) abdominal muscles measured (superior rectus abdominis not included), the initial frequency value of both median power frequency and mean power frequency was significantly lower for the experimental group compared with the control group (p<0.05). These results suggest that in patients with chronic low back pain there is a trend for more fatigue to occur in both lumbar and abdominal muscles than in the normal control group. This would seem to suggest that in treatment programs for patients with chronic low back pain, improvement of endurance in all trunk muscles should be considered.

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 )였고 여자 대상자의 연령범위는 26세에서 31세()였다. 실험방법 실험대상자는 피로유발수축전후 50% 최대등척성근수축을 수행하였다. 자료수집과 분석을 위해 LabVIEW 소프트웨어를 사용하였다. 결과 t

Trunk holding test (Sorensen test) appear to have more value than strength test in prediction the occurrence of low back pain. Electromyographic activity of trunk extensor muscles during these test may provide clues to the etiology of neuromuscular-based low back pain. This study investigated the difference in back muscle endurance between healthy adult men and women using surface electromyographic (EMG) power spectral analysis. Thirty hea1thy subjects (15 men and 15 women) performed an unsupported trunk holding test for 60 seconds. Recording surface electrodes were placed over the erector spinae medially and laterally at vertebral levels of and . Slope of total frequency was evaluated using the MP100WSW Fast Fourier Transform spectrum analysis program. The slopes of all indices of back muscle fatigue, except right , were significantly steeper in men than in women (p<0.05). Our results indicated that the trunk holding test using EMG power spectral analysis of erector spinae muscles is useful for the evaluation of fatigue rate of these muscles. Our results also showed a higher muscle endurance in healthy adult women than in men.