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Magnitude of changes in muscle endurance in the Biering-Sorensen test and changes in balance in subjects with LBP treated with muscle energy techniques

Wegner-Czerniak Katarzyna, Mączyński Jacek, Błaszczyk Anna, Ogurkowska Małgorzata Barbara

Acta of Bioengineering and Biomechanics

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2024

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Vol. 26, no. 1

89--97

EN

Manual therapy is used as a conservative treatment for people with low back pain (LBP). The scale of the problem encourages the search for the most effective methods to assess of manual treatment. Therefore, the aim of the study was to investigate magnitude of changes in muscle endurance using the Biering-Sorensen test (BST) and to analyse balance in patients with LBP treated with ERS and FRS muscle energy techniques (MET). Methods: The study included fifteen men with LBP (mean age: 42 years) working as automotive assemblers. Endurance of the biceps femoris (BF), gluteus maximus (GM) and erector spinae (ES) muscles were analysed using sEMG during the BST. The level of experienced pain, degree of disability and postural stability were also examined. Results before and after a three-week treatment cycle using MET were compared. Results: The MET therapy resulted in a reduction in pain ( p = 0.001), an improvement in the degree of disability ( p < 0.001) and an increase in the duration of the BST ( p < 0.001). After therapy, the values of the NMFs parameter indicating the degree of fatigue increased, i.e., ES muscle endurance increased, both right ( p = 0.004) and left ( p < 0.001). There was also a statistically significant decrease in the centre of pressure (COP) movement velocity in balance tests. Conclusions: The use of MET in patients with LBP increases muscle endurance, improves postural balance, and reduces pain levels on the VAS and disability levels according to the ODI. MET appears to be a good tool for preventing LBP.

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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.

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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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The Influence of Fatigue on Muscle Temperature

Bartuzi P., Roman-Liu D., Wiśniewski T.

International Journal of Occupational Safety and Ergonomics

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2012

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Vol. 18, No. 2

233--243

EN

The aim of the study was to investigate the possibility of using infrared (IR) thermography for assessing muscle fatigue during low effort. Three tests at constant levels of load 5, 15 and 30% of maximum voluntary contraction (MVC) lasting 5 min each were performed on a group of 10 men. Temperature and electromyographic (EMG) signal were registered from biceps brachii (BB). Analysis focused on the influence of load on the values and changes in time of muscle temperature. Correlations between temperature and EMG parameters (RMS, MPF and MF) were also analysed. Constant load sustained during the tests resulted in an increase in the temperature of BB. There were statistically significant correlations between temperature and EMG parameters for most subjects. Results of the study suggest that IR thermography can be an alternative or supplementary method for assessing muscle fatigue at low levels of contraction.

6

Development of Prolonged Standing Strain Index to Quantify Risk Levels of Standing Jobs

Halim I., Omar A. R.

International Journal of Occupational Safety and Ergonomics

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2012

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Vol. 18, No. 1

85--96

EN

Many occupations in industry such as metal stamping workers, electronics parts assembly operators, automotive industry welders, and lathe operators require working in a standing posture for a long time. Prolonged standing can contribute to discomfort and muscle fatigue particularly in the back and legs. This study developed the prolonged standing strain index (PSSI) to quantify the risk levels caused by standing jobs, and proposed recommendations to minimize the risk levels. Risk factors associated with standing jobs, such as working posture, muscles activity, standing duration, holding time, whole-body vibration, and indoor air quality, were the basis for developing the PSSI. All risk factors were assigned multipliers, and the PSSI was the product of those multipliers. Recommendations for improvement are based on the PSSI; however, extensive studies are required to validate their effectiveness.

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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.

9

Assessment of the Musculoskeletal Load of the Trapezius and Deltoid Muscles During Hand Activity

Roman-Liu D., Tokarski T., Kamińska J.

International Journal of Occupational Safety and Ergonomics

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2001

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Vol. 7, No. 2

179--193

EN

The purpose of the study was to analyse the influence of the precision of a task on tension and fatigue of the trapezius and deltoid muscles. Ten young men took part in experiments. Different levels of force and different frequencies of pressing a button defined the precision of the task. Surface electromyography (EMG) was used. Muscle tension and fatigue were reflected by 2 parameters of the EMG signal: the Root Mean Square amplitude related to the maximum value and changes in the Median Power Frequency. The results showed that hand activities influence the descending part of the trapezius muscle and do not influence the deltoid muscle, and that the precision of work can influence the examined muscles of the arm and shoulder even during work in which only the hand is involved in a performed task.