• Physical Therapy Rehabilitation Science
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• v.6 no.3
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• pp.127-133
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• 2017

Objective: The purpose of this study was to explore the effect of repetitive wrist extension task training with electromyography (EMG)-triggered neuromuscular electrical stimulation (NMES) for wrist extensor muscle recovery in patients with stroke. Design: Randomized controlled trial. Methods: Fifteen subjects who had suffered a stroke were randomly assigned to an EMG-triggered NMES group (n=8) or control group (n=7); subjects in both groups received conventional therapy as usual. Subjects in the experimental group received application of EMG-triggered NMES to the wrist extensor muscles for 20 minutes, twice per day, five days per week, for a period of four weeks, and were given a task to make a touch alarm go off by activity involving extension of their wrist. In the control group, subjects performed wrist self-exercises for the same duration and frequency as those in the experimental group. Outcome measures included muscle reaction time and spectrum analysis. Assessments were performed during the pre- and post-treatment periods. Results: In the EMG-triggered NMES group, faster muscle reaction time was observed, and median frequency also showed improvement, from 68.2 to 75.3 Hz, after training (p<0.05). Muscle reaction time was significantly faster, and median frequency was significantly higher in the experimental group than in the experimental group after training. Conclusions: EMG-triggered NMES is beneficial for patients with hemiparetic stroke in recovery of upper extremity function.

• The Journal of Korean Physical Therapy
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• v.30 no.4
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• pp.129-134
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• 2018

Purpose: This study aims to investigate the changes in pulmonary function, gait ability, and quality of life when NMES is applied along with CBE and to provide basic clinical data to be used in pulmonary rehabilitation guidelines for patients with COPD to treat patients with severe COPD. Methods: For this study, CBE and NMES of quadriceps femoris on both sides were applied to the experimental group (n=10), and only CBE was applied to the control group (n=10). For a pre-test, a 6-minute walk test was performed, and pulmonary function and health-related quality of life were measured. Moreover, an exercise program was applied to each group for 30 minutes per session, 5 times a week, for 6 weeks. After that, a post-test was conducted the same way as the pre-test. Results: In the within-group comparison, there were significant differences in forced expiratory volume in one second, 6-minute walk test and health-related quality of life between the experimental group and the control group (p<0.01)(p<0.05). In the between-group comparison, the experimental group showed an increase in forced expiratory volume in one second and 6-minute walk test (p<0.05) and showed a decline in health-related quality of life (p<0.05). Conclusion: The 6-weeks NMES program improved health-related quality in patients with severe COPD by increasing expiratory volume by reinforcing the function of quadriceps femoris. This finding implies that NMES could be an alternative mode for improving physical functions of patients with severe COPD, who cannot participate in a breathing exercise program or are reluctant to participate.

• The Journal of Korean Physical Therapy
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• v.26 no.5
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• pp.280-289
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• 2014

Purpose: This study was conducted in order to determine the stimulation variables which should be considered when neuromuscular electrical stimulation (NMES) is applied for a muscle under the normal innervation to minimize muscle fatigue and increase force-generating ability. Methods: A total of 23 healthy men participated in the study and all subjects were randomly assigned to the 1:1 group, 1:3 group, 1:5 group, and control group with on-off ratio of NMES. The subjects performed a fatigue task, consisting of 10 times of isometric contraction sustained by NMES. NMES using Russian current stimulation was applied to muscle fatigue and divided into three sessions by pulse frequency (10 bps, 30 bps, 90 bps). The EMG was recorded using an MP 100 system from the quadriceps femoris muscle in four groups. Results: The differences of delta MdF and delta MF of between on-off ratio groups of 10 bps, 30 bps, and 90 bps pulse frequencies were very significant (p<0.05). According to the results of post hoc of 10, 90 bps, it was greater in the 1:1 group and the 1:3 group compared with the 1:5 group, and no fatigue was observed in the control group. In 30 bps, it was greater in the 1:1 group compared with 1:3, 1:5, and control group (p<.05). Conclusion: Among NMES variables to minimize muscle fatigue, the larger on-off ratio by pulse frequency showed the lower muscle fatigue. Therefore, on-off ratio needs to be great enough, and will be more efficient with the frequency 30 bps rather than of 10 bps and 90 bps.

• Journal of the Korean Society of Physical Medicine
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• v.14 no.2
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• pp.125-135
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• 2019

PURPOSE: This study examined the effects of low frequency neuromuscular electrical stimulation (NMES) training on abdominal obesity in middle-aged women through electromyography and ultrasound. METHODS: Twenty-two middle aged women with abdominal obesity participated in the study. A low-frequency NMES device was used on the abdomen and waist of each subject for 20 minutes each (a total of 40 minutes) three times a week for eight weeks. The waist-hip ratio (WHR), weight and BMI (Body Mass Index) were measured. Electromyography (EMG) and ultrasound measurements were performed three times in total (pre-intervention, four weeks into the intervention, and eight weeks post-intervention) to examine the effects of low-frequency NMES on the abdominal muscle activity, muscle thickness, and subcutaneous fat. RESULTS: The results indicated a difference in the WHR and waist circumference before and after intervention (p<.05). The external oblique muscle (EO) showed a significant increase in muscle activity during all measurements taken post-intervention (p<.05). The abdominal subcutaneous fat thickness also showed a significant decrease between each measurement (p<.05). The test results showed that the abdominal subcutaneous fat thickness values taken eight weeks post-intervention were significantly lower than those taken pre-intervention and four weeks into the intervention (p<.05). CONCLUSION: These findings show that low-frequency NMES device training can be applied to middle-aged women with abdominal obesity to improve their body shape and exercise performance.

• Physical Therapy Korea
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• v.29 no.4
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• pp.269-273
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• 2022

Background: Neuromuscular electrical stimulation (NMES) is used for muscle strengthening. While voluntary muscle contraction follows Henneman et al.'s size principle, the NMES-induced muscle training disrespects the neurophysiology, which may lead to unwanted changes (i.e., declined balance ability). Objects: We examined how the balance was affected by abdominal muscle training with the NMES. Methods: Fifteen young adults (10 males and 5 females) aged between 21 and 30 received abdominal muscle strengthening with NMES for 23 minutes. Before and after the training, participants' balance was measured through one leg standing on a force plate with eyes open or closed. Outcome variables included mean distance (MDIST), root mean square distance (RDIST), total excursion (TOTEX), mean velocity (MVELO), and 95% confidence circle area (AREA) of center of pressure data. Two-way repeated measures analysis of variance was used to test if these outcome variables were associated with time (pre and post) and vision. Results: All outcome variables were not associated with time (p > 0.05). However, all outcome variables were associated with vision (p = 0.0001), and MVELO and TOTEX were 52.4% (45.5 mm/s versus 95.6 mm/s) and 52.4% (364.1 mm versus 764.5 mm) smaller, respectively, in eyes open than eyes closed (F = 55.8, p = 0.0005; F = 55.8, p = 0.0005). Furthermore, there was no interaction between time and vision (F = 0.024, p = 0.877). Conclusion: Despite the different neurophysiology of muscle contraction, abdominal muscle strengthening with NMES did not affect balance.

• The Journal of Korean Physical Therapy
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• v.35 no.5
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• pp.145-150
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• 2023

Purpose: This study examined the effects of ankle control training using neuromuscular electrical stimulation (NMES), leg muscle activation, and balance in stroke patients. Methods: Thirty-one stroke patients diagnosed with cerebral infarction and cerebral hemorrhage were selected for the study. The experimental group underwent ankle control training using NMES, while the control group applied NMES to the paretic tibialis anterior muscle for 30 minutes per session, five times a week for four weeks. The muscle activity changes were measured using surface electromyography, and balance parameters were evaluated using a functional reach test (FRT). Results: The intra-group comparison of the concentric muscle activity revealed improvements in the experimental group, including paretic tibialis anterior (TA) muscle (p<0.05), medial gastrocnemius muscle (MG) (p<0.01), and lateral gastrocnemius muscle (LG) (p<0.05), as well as MG (p<0.05), LG (p<0.05), soleus muscle (p<0.05) of the non-paretic side, and soleus muscle symmetry index (p<0.05). The intra-group comparison of the eccentric muscle activity showed improvements in the experimental group, including MG (p<0.01) and LG (p<0.01) of the paretic side, as well as MG (p<0.01), LG (p<0.01) of the non-paretic side, and LG symmetry index (p<0.01). The intra-group comparison of the functional reach test revealed significant differences in the test results in the experimental and control groups (p<0.05). Conclusion: Ankle control training using NMES had a positive effect on the changes in muscle activation and improved balance in patients with stroke.

• International Journal of Contents
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• v.5 no.4
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• pp.35-39
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• 2009

The purpose of this study was to evaluate the changes in skeletal muscle architecture and qualitative properties by muscle contraction force when neuromuscular electrical stimulation (NMES) of 50% MVIC was applied. Sixteen subjects (8 male, 8 female) without neuromuscular disease volunteered to participate in the study. All subjects were divided into two subgroups: control (no electrical stimulation) group and 50% maximal voluntary isometric contraction (MVIC) group. NMES training program was performed in the calf muscle three times a week for 10 weeks. Before and after the experiments, the MVIC of ankle plantar flexor was measured by the use of dynamometer, and the ultrasonography in the gastrocnemius medialis muscle was measured. The following results were obtained; MVIC was significantly increased in the electrical stimulation groups. Pennation angle, muscle density, and white area index also considerably changed in the electrical stimulation groups. In conclusion, the NMES training of 50% MVIC, comparative low level, improved the skeletal muscle architecture and the qualitative properties as well as the muscle contraction force.

• The Journal of Korean society of community based occupational therapy
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• v.5 no.1
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• pp.23-34
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• 2015

Objective : The purpose of this study is to investigate the effect of self swallowing exercise program with neuromuscular electrical stimulation(NMES) on swallowing function. Methods : Subjects who were diagnosed in dysphagia were randomly divided into the control group or experimental group. Both group were received NMES during 60 minutes with traditional swallowing therapy during 30 minutes. Additionally the experimental group was received self swallowing exercise during 30 minutes. We invested subject's characteristics through medical chart. We used VDS(Videofluoroscopic Dysphagia Scale) and PAS(Penetration Aspiration Scale) for assessing the swallowing function. Results : There were not significantly different in both group's pre swallowing function. The control group was significantly improved on pyriform sinus residue, aspiration, and VDS total score(p<.05). The experimental group was significantly improved on vallecular residue, pyriform sinus residue, and VDS total score(p<.05). Both group's difference of pre and post swallowing function were not significantly different. Conclusion : Self swallowing exercise and traditional swallowing therapy with NMES and traditional swallowing therapy with NMES are positive effect on swallowing function. The self swallowing exercise is not effective factor.

• Journal of the Korean Academy of Clinical Electrophysiology
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• v.3 no.1
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• pp.49-59
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• 2005

This study assigns each 8 of 24 normal persons to control group(Group I), strength increase group(Group II) and endurance increase group(Group III) to analyze differences in changes of strength and endurance with surface electromyography and kinetics according to application modes of neuromuscular electrical stimulation(NMES). Group I had not any treatment, group II performed 15 repeated contraction with 60% intensity of maximal voluntary isometric contraction(MVIC) by setting 10-sec on time and 50-sec off time and group III conducted 30 repeated contraction with 30% intensity of MVIC by setting 10-sec on time and 20-sec off time. For neuromuscular electrical stimulation, 2,500 Hz of Russian current, 35 pps of pulse rate and 200 of pulse width. Neuromuscular electrical stimulation was conducted by five times for total 4 weeks. Before and after experimentmotor unit action potential of vastus medialis, rectus femoris and vastus lateralis were measured with sEMG, median frequency(MDF) was analyzed, and thus the following results were obtained. There was significant difference in the period of measuring vastus medialis and rectus femoris in change of MDF and interaction among groups with analysis of surface electromyography before and after neuromuscular electrical stimulation(p<.001) and in particular, there was a remarkable change among groups according to the period of measurement. In conclusion, NMES influenced changes of strength and endurance according to its application modes and in particular, it was found that strength increment application had a significant influence on strength increment in applying short-time NMES.

• Journal of the Korean Academy of Clinical Electrophysiology
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• v.1 no.1
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• pp.1-15
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• 2003

The purpose of this study was to determine the effect of neuromuscular electrical stimulation(NMES) on the alteration of spinal motor neuron excitability. In this article, I would like to experiment on a standard capacity of clinical electrophysiology, a difference in applying methods and a clinical efficiency of NMES by Nerve conduction velocity. We used normal eight subjects without neuromuscular disease and all subjects participated 3 session, which at least 1 week between session. Participants classified according to each group in Antagonist, Agonist, Antagonist-Agonist by the NMES. The test was measured continuously pre test, post-test, post 20 minute test by EMG including H reflex, F wave, motor nerve conduction velocity(MNCV). The following results were obtained; 1. H-reflex latencies and H/M intervals were significantly increased in agonist and antagonist-agonist group(p<.01). 2. H-reflex amplitudes and H/M ratios were significantly decreased in agonist and antagonist-agonist group(p<.01). In agonist group, H-reflex amplitudes and H/M ratios were more significantly decreased than antagonist group. 3. F-wave latencies were significantly increased in agonist and antagonist-agonist group(p<.01). F/M intervals were significantly increased in antagonist-agonist group(p<.01). F wave conduction velocities were significantly increased in agonist and antagonist-agonist group(p<.01) but F/M ratios were not significant. 4. MNCV were significantly decreased in agonist(p<.01). These results lead us to the conclusion that agonist and Antagonist-agonist was significantly decreased excitability of spinal motor neuron. Conversely, Antagonist does not decreased. Therefore, A further direction of this study will be to provide more evidence that NMES have an effect on excitability of spinal motor neurons in UMN syndrome.