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Predicting muscle fatigue during dynamic contractions using wavelet analysis of surface electromyography signal

Shariatzadeh Mohammad Javad, Hadizadeh Hafshejani Ehsan, Mitchell Cameron J., Chiao Mu, Grecov Dana

Biocybernetics and Biomedical Engineering

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2023

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Vol. 43, no. 2

428--441

EN

Muscle fatigue is defined as a reduction in the capability of muscle to exert force or power. Although surface electromyography (sEMG) signals during exercise have been used to assess muscle fatigue, analyzing the sEMG signal during dynamic contractions is difficult because of the many signal distorting factors such as electrode movements, and variations in muscle tissue conductivity. Besides the non-deterministic and non-stationary nature of sEMG in dynamic contractions, no fatigue indicator is available to predict the ability of a muscle to apply force based on the sEMG signal properties. In this study, we designed and manufactured a novel wearable sensor system with both sEMG electrodes and motion tracking sensors to monitor the dynamic muscle movements of human subjects. We detected the state of muscle fatigue using a new wavelet analysis method to predict the maximum isometric force the subject can apply during dynamic contraction. Our method of signal processing consists of four main steps. 1- Segmenting sEMG signals using motion tracking signals. 2- Determine the most suitable mother wavelet for discrete wavelet transformation (DWT) based on cross-correlation between wavelets and signals. 3- Deoinsing the sEMG using the DWT method. 4- Calculation of normalized energy in different decomposition levels to predict maximal voluntary isometric contraction force as an indicator of muscle fatigue. The monitoring system was tested on healthy adults doing biceps curl exercises, and the results of the wavelet decomposition method were compared to well-known muscle fatigue indices in the literature.

2

Characterization of muscle fatigue in the lower limb by sEMG and angular position using the WFD protocol

Chaparro-Cárdenas Silvia L., Castillo-Castañeda Eduardo, Lozano-Guzmán Alejandro A., Zequera Martha, Gallegos-Torres Ruth Magdalena, Ramirez-Bautista Julian Andres

Biocybernetics and Biomedical Engineering

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2021

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Vol. 41, no. 3

933--943

EN

Lower limb muscle fatigue has been evaluated in previous studies to understand painrelated movement variability by analyzing different muscles using surface electromyography (sEMG) and angular position signals; however, further studies are needed to particularly understand strength loss due to gait and to inform the development of intelligent control systems for rehabilitation devices in the prevention and management of musculoskeletal or balance control disorders in the Latin American population. A pilot study was developed to characterize muscle fatigue using a walking fatigue detection (WFD) protocol, an instrumented orthosis and a treadmill. Electrical activity was acquired from Rectus Femoris (RF), Biceps Femoris (BF), Tibialis Anterior (TA) and Gastrocnemius Lateralis (GL) muscles, as well as the angular position of the hip and knee of sixteen healthy Latin-American women, aged 22–34 years, 63.5 ± 6 kg mass, and 161 ± 7 cm height. Data were analyzed with a one-way ANOVA analysis of variance and Tukey’s test. Preliminary results show that muscle fatigue is clearly identifiable and is represented by a decrease in both amplitude and frequency of the sEMG signal and lower limb angular position. Muscle fatigue was evident in 93.75% of the participants at the end of the test. 75% of the participants experienced muscle fatigue halfway through the test, of which 31.35% were unable to regain strength causing more muscles to fatigue, due to the extra effort they were enduring it was also found that when one muscle goes into fatigue, another muscle supports the action observing muscle compensation but without a uniform pattern.

3

Electromyographic assessment of muscle fatigue after the Biering–Sorensen test in subjects with low back pain who underwent the McKenzie treatment

Jabłońska Magdalena, Mączyński Jacek, Fryzowicz Anna, Ogurkowska Małgorzata B.

Acta of Bioengineering and Biomechanics

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2021

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Vol. 23, no. 3

87--96

EN

Purpose: Chronic low back pain is a common disorder affecting about 80% of the population, caused by a disorder in the muscular system. The main aim of this study was to assess muscle fatigue during the Biering–Sorensen Test in people with chronic low back pain who underwent the McKenzie treatment. Methods: Tests were conducted on 19 men (mean age of 41.4 years) with chronic non-specific lumbar-sacral pain syndrome, working in the seated position in front of a computer. Assessment of changes in fatigue of erector spinae, gluteus maximus and biceps femoris using surface electromyography during the Biering–Sorensen Test and subjective pain assessment using Visual Analog Scale were conducted on three test dates. Time-frequency representation of the electromyographic signal (Fourier transform) was used for the examination of muscle fatigue. The McKenzie method of diagnosis and therapy was applied before and between the tests. Results: The McKenzie therapy resulted in increased endurance (test duration) of the examined spinal muscles between the 1st and 3rd test date (p = 0.043), and a systematic decrease in pain assessment on the three test dates (p = 0.000–0.004). Correlations were obtained between slope coefficients of the simple regression of median frequency of electromyographic signals on the one hand and duration of the BST (p = 0.000–0.012) and anthropometric parameters (body mass, height and body mass index, p = 0.001–0.020) on the other. Conclusions: The McKenzie method is an effective tool in reducing the level of lumbar pain and improving muscle endurance.

4

Measurement of abdominal retractor loading and its effects on the surgeons arm

Hučko B., Čekan M., Horvát F., Chlebo O., Bachraty M., Čambal M.

Interdisciplinary Journal of Engineering Sciences

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2018

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Vol. 6, no. 1

60--63

EN

A load measuring apparatus integrated into an abdominal retractors and its methodology are presented. The measured forces offer new knowledge in the fields of surgery and may be useful in the design of new retractors and fixing frames as well as the investigation of tissue loading during surgical intervention. Effort required to hold the retractor is quantified for the surgeons forearm and the approximation of muscle fatigue can be evaluated with respect to the duration of surgical intervention.

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Design and Development of a Pressure Sensing Device for Analysing the Pressure Comfort of Elastic Garments

Senthilkumar M., Kumar L. A., Anbuman N.

Fibres & Textiles in Eastern Europe

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2012

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Vol. 20, no. 1 (90)

64-69

EN

In this paper, a pressure sensing device for analysing pressure comfort on elastic garments was designed and developed. The device was calibrated and tested on different compression garments for its reliability. This pressure comfort measurement device is used to measure the pressure between the human body and garments. The fabric resistance due to each and every body movement is noted to evaluate the effect of fabric compression on body muscles in order to assess the pressure comfort for sports persons. The new device proved that elastic garments certainly improve stamina and speed through its quick recovery and lower stress with higher elongation. There is a good correlation found between the pressure values given by the new sensing device and the Instron tester.

PL

Opracowano układ pomiarowy umożliwiający pomiar ciśnienia w układach ubiorów kompresyjnych mający istotny wpływ na komfort użytkowania takiej odzieży. Układ pozwala na pomiar ciśnienia pomiędzy ciałem człowieka a warstwa odzieży, również przy zróżnicowanych ruchach ciała, co jest niezbędne dla określenia komfortu odzieży np. w przypadku sportowców. Badania rożnych ubiorów kompresyjnych pozwoliły ocenić przyrząd jako dobrze nadający się do tego celu. Dzięki zastosowanemu przyrządowi udało się stwierdzić, że ubiory kompresyjne pozwalają na polepszenie zdolności wysiłkowej oraz szybkości regeneracji układów mięśniowych.

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EMG frequency during isometric, submaximal activity : a statistical model for biceps brachii

Solnik S., De Vita P., Grzegorczyk K., Koziatek A., Bober T.

Acta of Bioengineering and Biomechanics

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2010

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Vol. 12, no. 3

21-28

EN

The purpose of this study was to develop a statistical model to describe the electromyography (EMG) signal frequency changes during a submaximal isometric contraction. Thirty subjects performed a 30-second isometric contraction of the biceps brachii muscle at 80% of the maximal voluntary isometric force. Surface EMG electrodes recorded electrical activity of the biceps brachii. Zero-Crossing-Rate was calculated to identify EMG frequency shifts. The mean frequencies for every one-second period were used to calculate a linear relationship between frequency and time. A significant relationship ( p < 0.05) between slope and initial frequency value was identified. The model described EMG frequency changes during submaximal effort of biceps brachii up to 15 seconds. The prediction error was 9.8%. Modifying this equation to initial values of frequency of each participant decreased prediction error to 7.2%. These results demonstrate that despite individual differences between subjects it is possible to derive single equation that describes EMG alterations during submaximal, isometric contractions across a homogeneous group of people.