The Reproducibility of Electromyographic Data

1975 ◽  
Vol 2 (1) ◽  
pp. 41-46 ◽  
Author(s):  
Mary McF. Simpson ◽  
Andrew Richardson
Keyword(s):  
Muscle Activity ◽  
Statistical Significance ◽  
Electrical Interference ◽  
Low Magnitude

Electromyographic results may be influenced by electrical interference or artefacts. This investigation shows that when discrepancies occurred between readings made by different operators they were of low magnitude and rarely reached the level of statistical significance. Assuming that recordings are made under ideal conditions, the data may be accepted as a true and reproducible measure of muscle activity.

scholarly journals Effect of Isometric Hip Abduction on Foot and Ankle Muscle Activity and Medial Longitudinal Arch During Short-Foot Exercise in Individuals With Pes Planus

2020 ◽  
pp. 1-7
Author(s):  
Jung-Hoon Choi ◽  
Heon-Seock Cynn ◽  
Chung-Hwi Yi ◽  
Tae-Lim Yoon ◽  
Seung-Min Baik
Keyword(s):  
Muscle Activity ◽  
Statistical Significance ◽  
Standing Position ◽  
Medial Longitudinal Arch ◽  
Joint Stability ◽  
Abductor Hallucis ◽  
Pes Planus ◽  
Longitudinal Arch ◽  
Significant Difference ◽  
Hip Abduction

Context: The improvement of hip joint stability can significantly impact knee and rearfoot mechanics. Individuals with pes planus have a weak abductor hallucis (AbdH), and the tibialis anterior (TA) may activate to compensate for this. As yet, no studies have applied isometric hip abduction (IHA) for hip stability during short-foot exercise (SFE). Objective: To compare the effects of IHA on the muscle activity of the AbdH, TA, peroneus longus (PL), and gluteus medius (Gmed), as well as the medial longitudinal arch (MLA) angle during sitting and standing SFE. Design: Two-way repeated analyses of variance were used to determine the statistical significance of AbdH, TA, PL, and Gmed electromyography activity, as well as the change in MLA angle. Setting: University research laboratory. Participants: Thirty-two participants with pes planus. Intervention(s): The participants performed SFE with and without isometric hip abduction in sitting and standing positions. Main Outcome Measures: Surface electromyography was used to measure the activity of the AbdH, TA, PL, and Gmed muscles, and Image J was used to measure the MLA angle. Results: Significant interactions between exercise type and position were observed in terms of the PL muscle activity and in the change in MLA angle only, while other muscles showed significant main effects. The IHA during SFE significantly increased the AbdH muscle activity, while the TA muscle activity was significantly lower. The muscle activity of Gmed and PL was significantly increased in the standing position compared with sitting, but there was no significant difference with or without IHA. The change in the MLA angle was significantly greater in SFE with IHA in a standing position than in the other SFE conditions. Conclusions: IHA may be an effective method for reducing compensatory TA activity and increasing AbdH muscle activity during SFE for individuals with pes planus.

Comparison of Trunk Muscle Activity During Modified Side-Bridge Exercises and Traditional Side Bridge Exercise

2020 ◽  
Vol 29 (7) ◽  
pp. 963-969 ◽  
Author(s):  
Chi-Whan Choi ◽  
Jung-Wan Koo ◽  
Yeon-Gyu Jeong
Keyword(s):  
Analysis Of Variance ◽  
Muscle Activity ◽  
Repeated Measures ◽  
Statistical Significance ◽  
Compressive Load ◽  
University Hospital ◽  
Healthy Men ◽  
Bonferroni Adjustment ◽  
Repeated Measures Analysis ◽  
Significant Difference

Context: The modified side-bridge exercise is designed for some special situations in which it is impossible to tolerate the compressive load on the side supported during the side bridge, such as in the older people with a hip or knee replacement and even in athletes with shoulder pain. Objectives: To examine the effects of 3 modified side-bridge exercises on the spinal stability muscles compared with traditional side-bridge (TSB) exercises for healthy men. Design: The effects of different exercises on the muscle activities of the external oblique (EO), internal oblique (IO), and quadratus lumborum (QL) during TSB exercise, both legs lift on side lying (BLLS), torso lift on a 45° bench while side lying (TLBS), and wall side bridge (WSB) were analyzed with the 1-way repeated-measures analysis of variance. Setting: This study was conducted in a university hospital laboratory. Participants: A total of 20 healthy men were recruited for this study. Interventions: The participants performed TSB, BLLS, TLBS, and WSB in a random order. Main Outcome Measures: Surface electromyography measured the muscle activity of the EO, IO, and QL. A 1-way repeated-measures analysis of variance assessed the statistical significance of the EO, IO, and QL muscle activity. When there was a significant difference, a Bonferroni adjustment was performed. Results: BLLS and TLBS showed similar effects to TSB in the EO, IO, and QL muscle activity, whereas WSB showed significantly less QL muscle activity than TSB (P < .05). Moreover, TLBS was significantly greater in the muscle activity of QL and EO than WSB (P < .05). Conclusion: BLLS and TLBS may be effective rehabilitation techniques to activate EO, IO, and QL in patients who are unable to perform TSB as spine stability exercises.

Breathing route influences upper airway muscle activity in awake normal adults

1989 ◽  
Vol 66 (4) ◽  
pp. 1766-1771 ◽  
Author(s):  
R. C. Basner ◽  
P. M. Simon ◽  
R. M. Schwartzstein ◽  
S. E. Weinberger ◽  
J. W. Weiss
Keyword(s):  
Muscle Activity ◽  
Minute Ventilation ◽  
Statistical Significance ◽  
Upper Airway ◽  
Mouth Breathing ◽  
Emg Activity ◽  
Electromyographic Activity ◽  
Bipolar Electrodes ◽  
Inspiratory Resistance ◽  
Topical Nasal Anesthesia

Both nasal obstruction and nasal anesthesia result in disordered breathing during sleep in humans, and bypassing the nasal route during tidal breathing in experimental animals produces decreased electromyographic activity of upper airway (UA) dilating muscles. To investigate UA responses to breathing route in normal awake humans, we studied eight healthy males (ages 21–38 yr) during successive trials of voluntary nose breathing (N), voluntary mouth breathing (M), and mouth breathing with nose occluded (MO). We measured genioglossus electromyographic activity (EMGgg) with perorally inserted bipolar electrodes, alae nasi (EMGan) and diaphragm EMG activity (EMGdi) with surface electrodes, and minute ventilation (VE) with a pneumotachograph. Mean phasic inspiratory EMG activity of both UA muscles was significantly greater during N than during M or MO, even when a 2.5-cmH2O.l-1.s inspiratory resistance was added to MO (P less than 0.01). In contrast, neither EMGdi nor VE was consistently affected by breathing route. EMGgg during N was significantly decreased after selective topical nasal anesthesia (P less than 0.002); a decrease in EMGan did not achieve statistical significance. These data suggest that peak UA dilating muscle activity may be modulated by superficial receptors in the nasal mucosa sensitive to airflow.

scholarly journals Correspondence between laryngeal vocal fold movement and muscle activity during speech and nonspeech gestures

2004 ◽  
Vol 97 (3) ◽  
pp. 858-866 ◽  
Author(s):  
Christopher J. Poletto ◽  
Laura P. Verdun ◽  
Robert Strominger ◽  
Christy L. Ludlow
Keyword(s):  
Muscle Activity ◽  
Vocal Fold ◽  
Muscle Activation ◽  
Pearson Correlation ◽  
Statistical Significance ◽  
Correlation Coefficients ◽  
Normal Subjects ◽  
Activation Level ◽  
Posterior Cricoarytenoid ◽  
Opening And Closing

To better understand the role of each of the laryngeal muscles in producing vocal fold movement, activation of these muscles was correlated with laryngeal movement during different tasks such as sniff, cough or throat clear, and speech syllable production. Four muscles [the posterior cricoarytenoid, lateral cricoarytenoid, cricothyroid (CT), and thyroarytenoid (TA)] were recorded with bipolar hooked wire electrodes placed bilaterally in four normal subjects. A nasoendoscope was used to record vocal fold movement while simultaneously recording muscle activity. Muscle activation level was correlated with ipsilateral vocal fold angle for vocal fold opening and closing. Pearson correlation coefficients and their statistical significance were computed for each trial. Significant effects of muscle ( P ≤ 0.0005) and task ( P = 0.034) were found on the r (transformed to Fisher's Z′) values. All of the posterior cricoarytenoid recordings related significantly with vocal opening, whereas CT activity was significantly correlated with opening only during sniff. The TA and lateral cricoarytenoid activities were significantly correlated with vocal fold closing during cough. During speech, the CT and TA activity correlated with both opening and closing. Laryngeal muscle patterning to produce vocal fold movement differed across tasks; reciprocal muscle activity only occurred on cough, whereas speech and sniff often involved simultaneous contraction of muscle antagonists. In conclusion, different combinations of muscle activation are used for biomechanical control of vocal fold opening and closing movements during respiratory, airway protection, and speech tasks.

Evaluation of Fatigability of the Levator Veli Palatini Muscle during Continuous Blowing Using Power Spectra Analysis

2004 ◽  
Vol 41 (3) ◽  
pp. 320-326 ◽  
Author(s):  
Takashi Tachimura ◽  
Kanji Nohara ◽  
Koichi Satoh ◽  
Takeshi Wada
Keyword(s):  
Cleft Palate ◽  
Muscle Activity ◽  
Statistical Significance ◽  
Power Spectra ◽  
Mean Power ◽  
Mean Power Frequency ◽  
Spectra Analysis ◽  
Levator Veli Palatini ◽  
Velopharyngeal Incompetence ◽  
Power Frequency

Objective The purpose of this study was to compare the fatigability of the levator veli palatini (LVP) muscle during blowing in speakers who exhibit velopharyngeal incompetence with that from normal speakers by means of power spectra analysis. Design All subjects were instructed to blow into a tube for more than 10 seconds at maximum possible effort. The LVP muscle activity (electromyography) was sampled at 2 kHz for 10 seconds from the time when the oral air pressure during blowing was stabilized. These samples were subjected to Fast Fourier Transfer analysis with analytic windows of 0.5-second width. The electromyography mean power frequency slope with respect to time for each subject was estimated. Participants Three speakers with repaired cleft palate and three normal speakers were selected as subjects. Results The slopes of the regression lines for all three subjects with repaired cleft palate were negatively signed with statistical significance (t test, p < .01). The slopes for all of the normal speakers were negatively signed, but these were not statistically significant. Conclusion These results suggest that the LVP muscle of speakers with repaired cleft palate who exhibit varying degrees of velopharyngeal dysfunction may deteriorate more easily in comparison with the LVP muscle of normal speakers.

Imaging molecules adsorbed onto electrodes under potential control by scanning probe microscopy

1991 ◽  
Vol 49 ◽  
pp. 376-377 ◽  
Author(s):  
N.J. Tao ◽  
J.A. DeRose ◽  
P.I. Oden ◽  
S.M. Lindsay
Keyword(s):  
Surface Charge ◽  
Environmental Effects ◽  
Scanning Probe Microscopy ◽  
Statistical Significance ◽  
Electrochemical Methods ◽  
Surface Structures ◽  
Scanning Probe ◽  
Potential Control ◽  
Afm Imaging ◽  
Special Circumstances

Clemmer and Beebe have pointed out that surface structures on graphite substrates can be misinterpreted as biopolymer images in STM experiments. We have been using electrochemical methods to react DNA fragments onto gold electrodes for STM and AFM imaging. The adsorbates produced in this way are only homogeneous in special circumstances. Searching an inhomogeneous substrate for ‘desired’ images limits the value of the data. Here, we report on a reversible method for imaging adsorbates. The molecules can be lifted onto and off the substrate during imaging. This leaves no doubt about the validity or statistical significance of the images. Furthermore, environmental effects (such as changes in electrolyte or surface charge) can be investigated easily.

Influence of Maternal Education on Food Consumption and Energy and Nutrient Intake in a Group of Pre-School Children from Madrid

2003 ◽  
Vol 73 (6) ◽  
pp. 439-445 ◽  
Author(s):  
Navia ◽  
Ortega ◽  
Requejo ◽  
Perea ◽  
López-Sobaler ◽  
...  
Keyword(s):  
Food Consumption ◽  
School Children ◽  
Food Habits ◽  
Nutrient Intake ◽  
Maternal Education ◽  
Statistical Significance ◽  
Dietary Adequacy ◽  
Consumption Energy ◽  
Maternal Educational Level ◽  
Energy And Nutrient Intake

A study was conducted on the influence of maternal education level on food consumption, energy and nutrient intake, and dietary adequacy in 110 pre-school children from Madrid, Spain. With increasing maternal education, children consumed more sugar (p < 0.05), fruit (p < 0.05), and fish (p < 0.05). Snacking was more frequent with decreasing maternal education (p < 0.05). Though statistical significance was not reached, the consumption of pre-cooked foods was greater among children of mothers educated to a higher level, a phenomenon probably related to the work situation of these women. With respect to dietary composition, no significant differences were found between groups for macronutrient, fiber and energy intakes, except for energy supplied by polyunsaturated fatty acids (PUFA), which was greater in the children of less educated women (p < 0.01). This is probably due to their greater consumption of sunflower seed oil. The diets of children belonging to well-educated mothers came closer to meeting the recommended intakes for folate, vitamin C, and iodine. It would seem that maternal educational level influences the food habits of children. Mothers with less education may require special advice in this area.

Use of vascular closure devices for endovascular interventions requiring a direct puncture of PETE grafts

VASA ◽  
2018 ◽  
Vol 47 (2) ◽  
pp. 119-124 ◽  
Author(s):  
Artur I. Milnerowicz ◽  
Aleksandra A. Milnerowicz ◽  
Marcin Protasiewicz ◽  
Wiktor Kuliczkowski
Keyword(s):  
Statistical Significance ◽  
Vascular Complications ◽  
Vascular Complication ◽  
Inguinal Region ◽  
Closure Device ◽  
Manual Compression ◽  
Direct Puncture ◽  
Endovascular Interventions ◽  
Vascular Closure Devices ◽  
Closure Group

Abstract. Background: Effectiveness of vascular closure devices during endovascular procedures requiring a direct puncture of a vascular prosthesis placed in the inguinal region is unknown. Patients and methods: The retrospective analysis included 134 patients with a history of polyethylene terephthalate (PETE) graft implantation in the inguinal region. In 20 (15 %) patients, haemostasis was achieved with manual compression, in 21 (16 %) with the StarClose™, and in 93 (69 %) with the AngioSeal™ device. Results: The incidence of vascular complications in the manual compression group was higher (at a threshold of statistical significance) than in the device closure group (45.0 vs. 24.5 %, p = 0.059). The difference was considered statistically significant when manual compression was compared with the AngioSeal™ closure group (45.0 vs. 13.9 %, p < 0.01). The vascular complication rate in the StarClose™ group was significantly higher than in the AngioSeal™ group (71.4 vs. 13.9 %, p < 0.000001). While haematomas were the only vascular complications observed after application of AngioSeal™, both haematomas and pseudoaneurysms were found in the StarClose™ group. Conclusions: The AngioSeal™ vascular closure device provides better local haemostasis than the StarClose™ device or manual compression during endovascular interventions requiring a direct puncture of PETE grafts

Myoelectric Activity Differences in Three Learning Sessions

2002 ◽  
Vol 16 (2) ◽  
pp. 92-96
Author(s):  
Tiina Ritvanen ◽  
Reijo Koskelo ◽  
Osmo H„nninen
Keyword(s):  
High School Students ◽  
Muscle Activity ◽  
Muscle Tension ◽  
Emg Activity ◽  
Traditional Learning ◽  
Myoelectric Activity ◽  
School Students ◽  
Language Laboratory ◽  
Upper Trapezius ◽  
Muscle Groups

Abstract This study follows muscle activity in three different learning sessions (computer, language laboratory, and normal classroom) while students were studying foreign languages. Myoelectric activity was measured in 21 high school students (10 girls, 11 boys, age range 17-20 years) by surface electromyography (sEMG) from the upper trapezius and frontalis muscles during three 45-min sessions. Root mean square (RMS) average from both investigated muscles was calculated. The EMG activity was highest in both muscle groups in the computer-aided session and lowest in the language laboratory. The girls had higher EMG activity in both investigated muscle groups in all three learning situations. The measured blood pressure was highest at the beginning of the sessions, decreased within 10 min, but increased again toward the end of the sessions. Our results indicate that the use of a computer as a teaching-aid evokes more constant muscle activity than the traditional learning situations. Since muscle tension can have adverse health consequences, more research is needed to determine optimal classroom conditions, especially when technical aids are used in teaching.

Sign in / Sign up

Export Citation Format

Share Document