Evaluation of Swallowing Related Muscle Activity by Means of Concentric Ring Electrodes

Surface electromyography (sEMG) can be helpful for evaluating swallowing related muscle activity. Conventional recordings with disc electrodes suffer from significant crosstalk from adjacent muscles and electrode-to-muscle fiber orientation problems, while concentric ring electrodes (CREs) offer enhanced spatial selectivity and axial isotropy. The aim of this work was to evaluate CRE performance in sEMG recordings of the swallowing muscles. Bipolar recordings were taken from 21 healthy young volunteers when swallowing saliva, water and yogurt, first with a conventional disc and then with a CRE. The signals were characterized by the root-mean-square amplitude, signal-to-noise ratio, myopulse, zero-crossings, median frequency, bandwidth and bilateral muscle cross-correlations. The results showed that CREs have advantages in the sEMG analysis of swallowing muscles, including enhanced spatial selectivity and the associated reduction in crosstalk, the ability to pick up a wider range of EMG frequency components and easier electrode placement thanks to its radial symmetry. However, technical changes are recommended in the future to ensure that the lower CRE signal amplitude does not significantly affect its quality. CREs show great potential for improving the clinical monitoring and evaluation of swallowing muscle activity. Future work on pathological subjects will assess the possible advantages of CREs in dysphagia monitoring and diagnosis.

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Textile Concentric Ring Electrodes: Influence of Position and Electrode Size on Cardiac Activity Monitoring

Journal of Sensors ◽

10.1155/2018/7290867 ◽

2018 ◽

Vol 2018 ◽

pp. 1-9 ◽

Cited By ~ 2

Author(s):

Gema Prats-Boluda ◽

Yiyao Ye-Lin ◽

Francisco Pradas-Novella ◽

Eduardo Garcia-Breijo ◽

Javier Garcia-Casado

Keyword(s):

Low Cost ◽

Health Care Systems ◽

Cardiac Activity ◽

Signal Amplitude ◽

Activity Monitoring ◽

Concentric Ring ◽

Spatial Selectivity ◽

Care Systems ◽

Wave Morphology ◽

Signal Detectability

Continuous ECG monitoring can play an important role in the rapid detection of pathological signatures and arrhythmias. Current systems use electrodes with limitations in wearable long-term applications and spatial selectivity. In this work, two sizes of textile concentric ring electrodes (TCRE42 and TCRE50) were developed and tested for monitoring cardiac activity. The low-cost devices were found to be easy to implement and to potentially have the advantages of textile electrodes for being lightweight, stretchable, adjustable, washable, and long-lasting. Both TCREs yielded similar signal detectability of different ECG waves. The optimal P wave recording area (OPA) for detecting signals was on the upper right chest. Although the absolute signal amplitude of TCRE records was smaller than that of lead II, normalized amplitude in the OPA is similar for T wave and higher for P wave. The TCREs also allowed better analysis of P wave morphology and were able to detect more right and left atrial depolarization waves. TCRE48 showed slightly better detectability, normalized amplitude, and spatial selectivity than TCRE50 within the OPA. The authors consider the TCRE suitable for use in ubiquitous mobile health care systems, especially for atrial activity monitoring and diagnosis.

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The Activity of Surface Electromyographic Signal of Selected Muscles during Classic Rehabilitation Exercise

Rehabilitation Research and Practice ◽

10.1155/2016/4796875 ◽

2016 ◽

Vol 2016 ◽

pp. 1-9 ◽

Cited By ~ 2

Author(s):

Jinzhuang Xiao ◽

Jinli Sun ◽

Junmin Gao ◽

Hongrui Wang ◽

Xincai Yang

Keyword(s):

Lower Limb ◽

Muscle Activity ◽

Activity Level ◽

Core Stability ◽

Median Frequency ◽

Low Back ◽

Lower Limb Muscles ◽

Significant Difference ◽

Limb Muscles ◽

Rehabilitation Exercises

Objectives. Prone bridge, unilateral bridge, supine bridge, and bird-dog are classic rehabilitation exercises, which have been advocated as effective ways to improve core stability among healthy individuals and patients with low back pain. The aim of this study was to investigate the activity of seven selected muscles during rehabilitation exercises through the signal of surface electromyographic. Approaches. We measured the surface electromyographic signals of four lower limb muscles, two abdominal muscles, and one back muscle during rehabilitation exercises of 30 healthy students and then analyzed its activity level using the median frequency method. Results. Different levels of muscle activity during the four rehabilitation exercises were observed. The prone bridge and unilateral bridge caused the greatest muscle fatigue; however, the supine bridge generated the lowest muscle activity. There was no significant difference (P>0.05) between left and right body side muscles in the median frequency slope during the four rehabilitation exercises of seven muscles. Conclusions. The prone bridge can affect the low back and lower limb muscles of most people. The unilateral bridge was found to stimulate muscles much more active than the supine bridge. The bird-dog does not cause much fatigue to muscles but can make most selected muscles active.

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Bilateral Biomechanical Asymmetry During 30 Seconds Isokinetic Sprint-Cycling Exercise

LASE Journal of Sport Science ◽

10.1515/ljss-2016-0001 ◽

2015 ◽

Vol 6 (1) ◽

pp. 1-14

Author(s):

Indrek Rannama ◽

Kristjan Port

Keyword(s):

Muscle Activity ◽

Directional Asymmetry ◽

Thigh Muscle ◽

Vastus Lateralis Muscle ◽

Median Frequency ◽

Cycling Exercise ◽

Emg Amplitude ◽

Competitive Cyclists ◽

Bilateral Differences ◽

Leg Dominance

Abstract The purpose of present study was to examine the bilateral differences of pedalling kinetics and thigh muscle activity patterns according to leg dominance during the 30 seconds maximal cycling exercise and to analyse the relationships between asymmetries of pedalling kinetics and muscle activity. Methods: The pedalling power (POW), power production smoothness (PS) and EMG of VL, RF and BF of 17 competitive cyclists (19.2±1.6y.; 1.82±0.07m; 74.1±8.2kg) were measured bilaterally during maximal 30s isokinetic (cadence limit 100 rpm) seated cycling exercise. The dynamics of POW, PS and normalized EMG-RMS amplitude and median frequency (MF) of dominant (DO) and non-dominant (ND) side were measured. The directional asymmetry indexes (AI%) between DO and ND side were computed and compared with student t-test for paired samples. Correlation analyse between AI(%) of pedalling kinetics and EMG patterns was made. Results: The DO side POW and PS values were significantly (p<0.05) higher than ND during the all exercise time (except POW between 5-10 sec). No significant bilateral differences were found between normalized EMG amplitude values. The AI(%) of POW and PS were significantly lowered during the exercise. Significant correlations were found between AI (%)-s of PS and VL EMG MFr (r=-0.64) and between AI(%)-s of POW and VL normalized EMG amplitude (r=0.63).Conclusions: Results of the present study indicate that during 30 seconds maximal intensity cycling does exist leg dominance dependent asymmetries in pedalling power patterns, which decreased during the exercise and was related with bilaterally asymmetry of vastus lateralis muscle firing patterns.

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Changes in muscle activity with exercise-induced fatigue in Thoroughbred horses

Comparative Exercise Physiology ◽

10.3920/cep200044 ◽

2020 ◽

pp. 1-10

Author(s):

Y. Takahashi ◽

K. Mukai ◽

H. Ohmura ◽

T. Takahashi

Keyword(s):

Muscle Activity ◽

Extensor Digitorum Longus ◽

Gluteus Medius ◽

Extensor Digitorum ◽

Stride Frequency ◽

Median Frequency ◽

Propulsive Force ◽

Triceps Brachii ◽

Frequency Changes ◽

Exercise Induced

Understanding the effects of fatigue can provide guidance for training regimens and injury prevention. We have previously reported that the integrated-electromyogram (iEMG) values of the M. gluteus medius and brachiocephalicus decreased with exercise-induced fatigue, whereas those of the M. longissimus dorsi and infraspinatus were not affected. We hypothesised that exercise-induced fatigue would decrease the activities of the muscles associated with propulsive force but not associated with joint stabilisation. Surface EMG recordings of the forelimb muscles (M. triceps brachii, common digital extensor, ulnaris lateralis), and hindlimb muscles (M. semitendinosus, extensor digitorum longus, extensor digitorum lateralis and flexor digitorum lateralis) were conducted on eight Thoroughbreds. Horses galloped on a treadmill (grade, 3%) at a constant speed (12.6-14.8 m/s) until they could not maintain their position with minimal human encouragement (~5 min). The stride frequency, iEMG for a stride and median frequency during muscle discharge were calculated every 30 s. These parameters were compared between the start and end of the test phase for the leading and trailing limbs. The stride frequency (P<0.01) and iEMG values of the M. semitendinosus in both the leading (P<0.01) and trailing limbs (P<0.05) and those of the M. extensor digitorum longus in the trailing limbs (P<0.05) significantly decreased at the end of the test. No median frequency changes were observed in the assessed muscles. Although muscular fatigue itself was not detected, observed fatigue caused by high-intensity exercise resulted in inability to maintain speed, which was associated with decreased iEMG values in the hip extensor muscles that generate propulsive force. In contrast, almost all muscles that stabilise joints were unaffected by fatigue. One exception was the decreased muscle activity observed in the M. extensor digitorum longus of the trailing limb, which may suggest unstable ground contact. Muscle activity changes with fatigue might be associated with muscle functions.

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Forelimb brachial muscle activation patterns using surface electromyography and their relationship to kinematics in normal dogs walking and trotting

Comparative Exercise Physiology ◽

10.3920/cep13026 ◽

2014 ◽

Vol 10 (1) ◽

pp. 13-22 ◽

Cited By ~ 5

Author(s):

T.C. Garcia ◽

B.K. Sturges ◽

S.M. Stover ◽

K. Aoki ◽

J.M. Liang ◽

...

Keyword(s):

Muscle Activity ◽

Surface Electromyography ◽

Muscle Activation ◽

Biceps Brachii ◽

Elbow Flexor ◽

Median Frequency ◽

Joint Angles ◽

Muscle Activation Patterns ◽

The Right ◽

Elbow Extensor

The objective of this study was to determine activity of the elbow flexor and elbow extensor groups of muscles relative to shoulder and elbow joint kinematics in normal walking and trotting dogs using surface electromyography (EMG), and to determine if muscle activity varies with gait or limb. Ten healthy mixed-breed dogs were walked and trotted across embedded force plates in a 6 m walkway while simultaneously recording muscle activation using surface EMG positioned over the biceps brachii (elbow flexor group) and triceps brachii (elbow extensor group); peak shoulder, elbow, and carpal joint angles from motion capture, and ground reaction forces. EMG magnitude, timing, and power spectral density (PSD) were used to analyse muscle activity. The effects of gait type and limb side on EMG measures and joint angles were assessed using an analysis of variance. Results showed that the elbow flexor group was maximally active at end of stance. The elbow extensor group was maximally active at the beginning of stance. Muscle activity occurred earlier in the gait phase (stance or swing) in the trot compared to the walk. The amplitude, frequency at maximum PSD (elbow flexor group only) and the median frequency were larger on the right side than on the left side. The maximum PSD and integrated PSD were larger on the left side than the right side. These data provide a reference for identifying abnormalities associated with orthopaedic, neurological, or rehabilitative changes. Limb asymmetry observed in muscle activation in clinically normal dogs should be further evaluated.

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Relation between electromyogram and force in fatigue

Journal of Applied Physiology ◽

10.1152/jappl.1985.59.3.821 ◽

1985 ◽

Vol 59 (3) ◽

pp. 821-825 ◽

Cited By ~ 17

Author(s):

H. Kranz ◽

J. F. Cassell ◽

G. F. Inbar

Keyword(s):

Firing Rate ◽

Action Potentials ◽

Voluntary Contraction ◽

Median Frequency ◽

Root Mean Square Amplitude ◽

Compound Action Potentials ◽

Proportional Increase ◽

Late Adaptation ◽

The Relationship ◽

Compound Action

The relationship between the surface electromyogram (SEMG) and force was examined during maximal voluntary contraction (MVC). Isometric MVC of elbow flexors were studied in 18 subjects who performed 27 trials, each consisting of six MVCs lasting 45 s at intervals of 30 s. There was a decrease in the median frequency (Fm) of the SEMG and of the compound action potentials (CAP) during MVC. The CAPs demonstrated that the fall in Fm was associated with a proportional increase in signal power, whereas CAP amplitude did not decrease, indicating intact neuromuscular transmission. The SEMG root-mean-square amplitude remained fairly constant, progressively deviating from force with time of contraction (r = 0.40). When SEMG amplitude was corrected for the Fm change, it tracked force more closely (r = 0.68), indicating a fall in motoneuron drive during MVC. The corrected SEMG was used to calculate the change in the generalized firing rate of motoneurons. The firing rate decreased 60% in the first and sixth contractions, tracked force closely, and corresponded to the firing rate fall seen in late adaptation of motoneurons (r = 0.90, P less than 0.001).

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Advanced Rock Climbers Exhibit Greater Finger Force and Resistance to Fatigue Compared to Novices During Treadwall Climbing

10.1101/2020.04.27.20077560 ◽

2020 ◽

Author(s):

Philip F. Ferrara ◽

James Becker ◽

John G. Seifert

Keyword(s):

Muscle Activity ◽

Force Plate ◽

Force Production ◽

Median Frequency ◽

Finger Force ◽

Flexor Muscle ◽

Significant Group ◽

Maximum Voluntary Isometric Contraction ◽

Before And After ◽

Flexor Digitorum

AbstractBackgroundThe purpose of the study was to investigate the effects of rock climbing experience on time to fatigue (TTF), finger flexor force production relative to body weight (REL FP), and changes in finger flexor muscle activity during tread wall climbing.MethodsEight advanced and seven novice sport rock climbers performed a climbing protocol on a treadwall system. The protocol consisted of climbing for six 5-minute intervals or until voluntary failure. A mounted force plate was used to measure finger force production before and after the climbing protocol. Subjects performed a 20-second maximum voluntary isometric contraction (MVIC) against the force plate with the dominant and non-dominant fingertips in a common climbing hand configuration known as a half crimp. Muscle activity was monitored with electromyographic electrodes placed bilaterally over the subject’s flexor digitorum superficialis. Median frequency (MF) and root mean square (RMS) were analyzed. The treadwall was set at a difficulty of 9 IRCRA/5.9 YDS. It rotated at 7 m/min and was fixed at 7° overhanging.ResultsSignificant group differences were observed in subject characteristics, TTF (30±0 vs. 25.7±3.6 min), REL FP (5.6±1.2 vs. 3.2±0.9 N/kg BW), ΔFP (+1.5±12.3% vs. -31±16%), and ΔMF (+6.3±22.4% vs. -17.6±10.9%).ConclusionThe results of this study demonstrate that advanced climbers possess greater finger flexor force production and resistance to fatigue compared to novices during bouts of climbing on a treadwall system. This may be attributed to physiological changes due to years of training, such as metabolic adaptations and oxygenation capacity in the forearm musculature.

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