• Journal of the Korean Institute of Navigation
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• v.20 no.4
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• pp.81-98
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• 1996

The purpose of this study was analysis of the muscle action in physical exercise in the rolling machine. The rolling machine moved by eletric power-driven was made to keep the constant cycle and size of rolling. The subjects of this study consist of 4 seaman(SM) and 4 landman (LM). The experiment analyzed the muscle power of lower and upper limbs by Intergrated Electromyogram(IEMG). The measurement was made on the ground, and 6 and 8 degrees of rolling separately. This study concludes as follows ; including analysis of IEMG of heavy exercise in two hands curl, a standstill walking and just standing. 1. IEMG of the lower limbs when standing. 1) In 6 degrees of rolling, for the landman(LM), vastus medialis m.(9.73), vastus lateralis m.(9.55), and rectus femores m.(8.73) acted more. As for the seaman(SM), tibialis anterior m.(5.38), biceps femores m.(5.05), and gastrocnemius m.(4.47) acted more. 2) In 8 degrees of rolling, in common, for both LM and SM, it were vastus medialis m.(11.20 and 8.97), vastus lateralis m.(16.20 and 4.63), and tibialis anterior m.(5.13 and 4.47). 3) It was showed that IEMG of LM was larger than that of SM. 2. IEMG of the lower limbs when walking. 1) On the ground, for the LM, gastrocnemius m.(7.08), vastus medialis m.(6.65), and vastus latralis m.(6.60) acted more. As for the SM, vastus lateralis m.(7.08), vastus medialis m.(6.58) and restus femores m.(5.10) acted more. 2) In both 8 and 6 degrees of rolling, vastus medials m.(14.50 and 11.98), vastus lateralis m.(10.10 and 14.10), and gastrocnemius m.(11.75 and 7.10) acted more in two groups. 3) It was showed that IEMG of LM was larger than that of SM. 3. IEMG of the lower limbs when heavy exercise(two hands curl). 1) On the ground, for the LM, vastus lateralis m.(21.68), vastus medialis m.(16.08), and rectus femores m.(14.08) acted more. As for the SM, tibialis anterior m.(16.08), vastus medialis m.(14.58), and vastus lateralis m.(8.78) acted more. 2) In 8 and 6 dgrees of rolling, it were vastus medialis m.(17.05 and 12.45), vastus lateralis m.(37.98 and 17.08), and tibialis anterior m.(19.83 and 13.20). 3) It was showed that IEMG of LM was larger than that of SM. 4. IEMG of the upper limbs when heavy exercise. 1) On the ground, the brachialis m.(44.30 and 17.80), and biceps brachii m.(13.40 and 25.10) acted more in two groups. 2) In both 6 and 8 degrees of rolling, the brachialis m.(37.60 and 24.35), and biceps brachii m.(11.38 and 7.97) acted more in two groups. 3) It was showed that IEMG of SM was larger than that of LM.

• Korean Journal of Applied Biomechanics
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• v.20 no.3
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• pp.303-310
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• 2010

The purpose of this study was (a)to compare electromyographic (EMG) activities and physiological variables on the development of fatigue induced by ergometer test, (b)to determine investigate the differences in the stage of fatigue between the electromyographic characteristics and physiological variables. Nine male university students who have no musculoskeletal disorder were recruited as the subjects. The electromyographic characteristics(peak IEMG, average IEMG, median frequency, mean edge frequency) and physiological variables(HR, RPE, blood lactate) were determined for each stage(15, 30, 45, 60 minutes, all out). For each dependent variable, one-way analysis of variance(ANOVA) with repeated measures and correlation analysis were performed to test if significant difference existed(p<.05). The results showed that peak IEMG, average IEMG from low extremity and physiological variables were significantly increased during the all-out stage. EMG parameters in VL, VM show significantly correlation with physiological variables during whole stages. This indicated that IEMG values may be proper parameters to determine muscle fatigue rather than physiological variables.

• Korean Journal of Applied Biomechanics
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• v.15 no.1
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• pp.207-219
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• 2005

The purpose of this study was to determine the effect of the foot rotation on the lower limb muscles. Fourteen subjects performed step-up/step-down at a cadence of 80 beats/min, exercises with the foot neutral, $35^{\circ}$ internally rotated, and $35^{\circ}$ externally rotated, respectively. For each variable, a one-way analysis of variance (ANOVA) was used to determine whether there were significant differences between genders and among the eight types of jump. When a significant difference was found in jump type, post hoc analyses were performed using the Tukey procedure. A confidence level of p < .05 was used to determine statistical significance. The results showed that significant changes in averaged IEMG values occurred with the internal rotation of the foot in the lateral gastrocnemius during the knee extension, and in the semitendinosus during the knee flexion. During the knee extension, however, the internal rotation of the foot produced a significantly lower Averaged IEMG values than the neutral foot position in the medial gastrocnemius. The results also found that the peak IEMG activity of the rectus femoris during the knee extension for the external rotation of the foot was Significantly higher than the corresponding values in the neutral position of the foot, while the intenal rotaion of the foot exhibited a significant difference with the neutral position of the foot in the semitendinosus during the knee flexion. In general, the foot rotation position did not influence the average IEMG and Peak IEMG values of most muscles. The practice of adopting foot rotation to selectively strengthen individual muscles of the lower limb was not supported by this study. The external rotation of the foot produced high muscle activities in the quadriceps during the knee extension. For the knee extension, therefore, maintaining a laterally rotated position should be need for stable and comfortable position.

• Physical Therapy Korea
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• v.10 no.1
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• pp.109-128
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• 2003

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.

• Korean Journal of Applied Biomechanics
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• v.18 no.4
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• pp.125-133
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• 2008

The purpose of this study was to compare EMG activities on the lower limb muscles during power walking and mormal walking. Seventeen subjects who have no known musculoskeletal disorders performed walking exercise at a cadence of 140 beats/min. After surface electrodes were attached to rectus femoris, vastus medialis, vastus lateralis, biceps femoris, tibialis anterior, medial gastrocnemius, averageed IEMG and peak IEMG, were measured. The result showed that the power walking did influence the averaged IEMG and peak IEMG. The EMG activity of the quadriceps during power walking was significantly higher than the corresponding values in normal walking during most phases. The averaged IEMG and peak IEMG of gastrocnemius muscles at the end of the double limb stance increased significantly when going from normal walking to power walking. The results indicate that power walking had greater effect on EMG activities on the lower limb muscles and demonstrate that the wide range of benefits can be obtained from power walking in respect to health and fitness. This study suggests that power walking has the potential to improve aerobic fitness and assist in weight management.

• 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 Korean Academy of Clinical Electrophysiology
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• v.9 no.2
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• pp.1-6
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• 2011

Purpose : This study aims to examine changes in electromyogram (EMG) signals detected from the tibialis anterior muscle during repetitive contraction exercises in normal female adults. Methods : The subjects of this study were 10 normal adult females without any musculoskeletal or nervous system disorders. A total of 30 contractions were made repetitively with maximal voluntary contraction exercise for six seconds and a resting time for three seconds. Changes in muscle contractions were measured using dynamometer and EMG signals such as root mean square (RMS), integrated EMG (IEMG), and median frequency (MDF). Results : The result of measurement showed no significant differences in IEMG and RMS in accordance with the increase in the number of contractions. MVIC and MDF showed significant differences in accordance with the increase in the number of contractions (p<0.05). Conclusion : This study demonstrated that repetitive tibialis anterior muscle contraction resulted in a significantly different MVIC and MDF but no significant differences in IEMG and RMS. Therefore, compared to other lower leg muscles, the tibialis anterior muscle is a low-frequency muscle and therefore electrophysiological characteristics of the muscle should be considered in different exercise methods.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.6 no.1
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• pp.51-58
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• 2012

In this study, the active exercise load control system was developed that monitors patient's muscular condition based on EMG signals and controls the load by biofeedback in real-time. In order to select appropriate muscular parameter for the system, the pre-exercise test was performed to obtain EMG signals from healthy 12 males. Subsequently, the main exercise test was performed to evaluate the active exercise load control system based on IEMG: a selected muscular parameter, on healthy 10 males without musculoskeletal disorder. The accuracy and availability of developed system were confirmed through observing changes between exercise load and IEMG. A correlation was analyzed between the fatigue of muscles and RPE indicating the individual subjective fatigue. As a result, the active exercise load control system that was suggested in this study could be useful to control the initial load-balancing and the amount of exercise appropriate for individual in rehabilitation exercise therapy.

• Journal of the Institute of Electronics and Information Engineers
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• v.53 no.4
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• pp.142-148
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• 2016

Recently, human identification using various biological signals has been studied and human identification based on the gait has been actively studied. In this paper, we propose a human identification based on the EMG(Electromyography) signal of the thigh muscles that are used when walking. Various features such as RMS, MAV, VAR, WAMP, ZC, SSC, IEMG, MMAV1, MMAV2, MAVSLP, SSI, WL are extracted from EMG signal data and ANN(Artificial Neural Network) classifier is used for human identification. When we evaluated the recognition ratio per channel and features to select approptiate channels and features for human identification. The experimental results show that the rectus femoris, semitendinous, vastus lateralis are appropriate muscles for human identification and MAV, ZC, IEMG, MMAV1, MAVSLP are adaptable features for human identification. Experimental results also show that the average recognition ratio of method of using all channels and features is 99.7% and that of using selected 3 channels and 5 features is 96%. Therefore, we confirm that the EMG signal can be applied to gait based human identification and EMG signal based human identification using small number of adaptive muscles and features shows good performance.

• Korean Journal of Applied Biomechanics
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• v.14 no.2
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• pp.167-178
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• 2004

The purpose of this study was to describe and compare the selected electromyographical muscle activities of trunk and hip during Professional and Amateur golfer's Iron swing. Using surface electromyography, we evaluated muscle activities in 6 male professional golfers and 6 male amateur golfers during the golf iron swing. Surface electrodes were used to record the level of muscle activity in the right abdominal oblique, left abdominal oblique, right erector spinae, left erector spinae, right rectus abdominis, left rectus abdominis, right gluteus maximus, left gluteus maximus muscles during the golfer's swing. These signals were compared with IEMG(Integrated EMG) which was normalized by %RVC(Reference voluntary contraction). The golf swing was divided into three phases: take away, forward swing-acceleration, follow-through. We observed patterns of trunk muscle activity throughout three phases of the golf swing. The results can be summarized as follows: LES(Left Erector spinae) had statistically significant difference in take away and forward swing-acceleration phases. It was showed no significant difference in follow-through phase.