Wyniki wyszukiwania - Biblioteka Nauki

1

Experimental identification of a mathematical model of human operator working under mental stress

100%

Kopyt A. , Zużewicz K. , Bartuzi P.

Acta of Bioengineering and Biomechanics

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2017

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tom Vol. 19, no. 3

177--185

EN

In engineering the human is considered as one of the system elements. In most studies, his/her model remains unchanged due to the external factors. The present study shows that a relation between the mental stress and human dynamics cannot be neglected. The dynamic characteristics of the operator model change due to external stimuli, i.e., mental stress. The aim of this study was to present identification of a mathematical human model and measurement methodology of the mental stress level. To determine the level of human response to external stimuli, the electrocardiography (ECG) and electromyography (EMG) methods were applied. The results showed difference in model parameters that cannot be neglected during the modeling of the human operator. The present study points to the need of developing simplified human models, taking into account external stimuli that have direct impact on his/her effectiveness. Some interdisplinary investigation provide may benefits combining part of the automation and ergonomics research areas.

2

Analiza aktywności fali wolnej w przewodzie pokarmowym szczura z zastosowaniem metody FFT

100%

Jung A. , Królczyk G. , Thor P.

Bio-Algorithms and Med-Systems

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2005

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tom Vol. 1, no. 1/2

87--88

PL

Celem pracy było zastosowanie transformaty Fouriera do znalezienia częstotliwości fali wolnej generowanej w przewodzie pokarmowym szczurów w normalnych warunkach fizjologicznych, jak i po zadziałaniu odpowiedniego bodźca, co może okazać się pomocne w opracowaniu nieinwazyjnych metod diagnozowania wybranych schorzeń przewodu pokarmowego. Sygnał elektryczny był zbierany poprzez elektrody umocowane na trzonie żołądka i końcowym odcinku dwunastnicy, następnie wygładzany i poddawany analizie. Do analizy sygnału zastosowano szybką transformatę Fouriera (FFT), która pozwoliła na znalezienie częstotliwości charakterystycznych. Częstotliwość fali wolnej była większa dla dwunastnicy niż dla żołądka, a podanie wazopresyny powodowało zwiększenie częstotliwości fali wolnej w żołądku.

EN

The goal of this study was to assess the frequency of the basic electric rhythm generated in the alimentary tract of rats, both in the physiological conditions and when pharmacological stimulus was affecting. The obtained results should be helpful to work out a new non-invasive diagnostic method for selected gastric diseases. The electrical activity was recorded using silver electrodes implanted on the stomach and the duodenum, and connected to amplifiers. The smoothed signal of electrical activity was analyzed by means of fast Fourier transform. The characteristic frequencies were determined showing that the basic electric rhythm was much higher for the duodenum than for the stomach. Moreover, the application of vasopressin caused significant increase of the basic electric rhythm in the stomach.

3

Sterowanie manipulatorem nasobnym w oparciu o sygnały EMG

100%

Jankowski J. , Ziemek K.

Mechanik

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2018

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tom R. 91, nr 7

582--584

PL

Integracja człowieka z egzoszkieletem – tak, aby poprawnie odzwierciedlał on zamiary użytkownika w zakresie ruchu kończyny górnej – wymaga zastosowania odpowiedniej metody sterowania, zawierającej algorytm wykrywania intencji. W artykule przedstawiono założenia dotyczące budowy egzoszkieletu kończyny górnej, a także proponowaną procedurę badawczą oraz wstępnie opracowane metody sterowania manipulatora wspomagającego, bazujące na analizie charakterystyki sygnału elektromiograficznego (EMG) oraz zastosowaniu sieci neuronowych.

EN

Human integration with the exoskeleton, so that it correctly reflects the intentions of the user, requires the use of an appropriate control method containing an intent detection algorithm. The article presents the assumptions concerning the construction of the upper limb exoskeleton, the preliminary research procedure and the pre-developed methods of controlling the assistance manipulator based on the analysis of the electromyographic signal (EMG) characteristics and the use of neural networks. KEYWORDS: exoskeleton, control method, EMG

4

Influence of upper extremity position on EMG signal measures calculated in time, frequency and time-frequency domains

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Wang J. , Bartuzi P. , Roman-Liu D.

Acta of Bioengineering and Biomechanics

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2013

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tom Vol. 15, no. 4

83--91

EN

The aim of this study was to investigate the relationship between time-frequency, time and frequency measures when considering various upper extremity positions below the level of the shoulder and in trapezius as well as deltoideus muscles. During the experiment, 15 subjects performed a task that involved screwing and unscrewing a screw cap on a board in six different locations, i.e., there were six upper extremity positions. Variables were calculated in the time, frequency and time-frequency domains on a recorded EMG signal. The results showed that parameters analyzed in the time-frequency domain were more sensitive to changes in position than parameters analyzed in the frequency domain.

5

Metody obróbki danych EMG

100%

Serej M. , Skublewska-Paszkowska M.

Journal of Computer Sciences Institute

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2017

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tom Vol. 3

38--45

PL

W artykule zostały przedstawione metody obróbki danych badania elektromiograficznego (EMG) oraz analiza sygnału EMG przy pomocy zaimplementowanej autorskiej aplikacji. Aplikacja służy do wczytania sygnału EMG zapisanego w pliku o rozszerzeniu .C3D. Analizę przeprowadzono pod względem największej aktywności mięśni podczas wykonywania ćwiczeń rejestrowanych przy pomocy techniki Motion Capture.

EN

The article presents both the methods of data processing of electromyography (EMG), and EMG signal analysis using the implemented piece of software. This application is used to load the EMG signal stored in a file with the .C3D extension. The analysis was conducted in terms of the highest muscles activaton during exercise recorded with Motion Capture technique.

6

The Research on Exoskeletons with Focus on the Locomotion Support

100%

Wang J. , Lyu L.

Pomiary Automatyka Robotyka

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2020

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tom R. 24, nr 2

17--22

EN

This paper summarizes the research on exoskeletons focusing on locomotion support and presenting their general features including the general control approaches. The major fields of exoskeleton applications are focused, namely the military and medical fields. The results of our research on muscles activation during human walking are shortly described. The current developmental trends are outlined in the conclusions part.

PL

W niniejszym artykule podsumowano wyniki badań przeprowadzonych nad egzoszkieletami przeznaczonymi do wspomagania czynności ruchowych. Przedstawiono ich główne cechy, a także główne podejścia ich sterowania. Podstawowymi obszarami użycia egzoszkieletów są zastosowania wojskowe i medyczne. Opisano zwięźle wyniki badań nad aktywacją mięśni podczas chodzenia przez człowieka. Obecne trendy rozwojowe przedstawiono w podsumowaniu.

7

Ocena obciążenia mięśni kończyny górnej podczas użytkowania rękawic ochronnych do ochrony przed nożami ręcznymi

100%

Tokarski T. , Irzmańska E.

Zeszyty Naukowe Małopolskiej Wyższej Szkoły Ekonomicznej w Tarnowie

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2017

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nr 3(35)

105-119

PL

W przypadku wykonywania przez pracowników czynności zawodowych przy narażeniu rąk na przecięcie i przekłucie nożami ręcznymi ważny jest pewny chwyt oraz odpowiednia wrażliwość dotykowa rąk. Nieprawidłowo dobrane pod względem ergonomicznym rękawice mogą wpływać ujemnie na komfort użytkowania związany z obniżeniem precyzji, wrażliwości dotykowej, siły chwytu i zręczności, co poprzez zwiększone obciążenie mięśni może powodować wzrost wypadkowości w miejscu pracy. Celem autorów artykułu była ocena obciążenia mięśni kończyny górnej podczas użytkowania wybranych wariantów rękawic chroniących przed przecięciami i ukłuciami nożami ręcznymi. Rękawice dobrano w zależności od zakresu czynności prac wykonywanych przy rozbiórce mięsa. Obciążenie mięśni badano podczas wykonywania dwóch testów standardowych (test siły ciągnięcia cylindra według PN-EN 1082-2:2002 oraz test zdolności manipulacyjnych na tablicy Purdue Pegboard) i trzech testów opracowanych z uwzględnieniem sposobu wykonywania pracy przez pracowników korzystających z rękawic ochronnych. Użytkowanie rękawic ochronnych nie wpływa znacznie na obciążenie mięśni, jednak ma bardzo duży wpływ na sposób wykonywania pracy. Zmniejszenie parametrów określających sprawność kończyny górnej sięga nawet 250%, czyli sprawność zmniejsza się ponad dwukrotnie. W związku z tym, w celu zapewnienia bezpiecznych warunków pracy przy rozbiorze mięsa, należy uwzględnić mniejszą sprawność ręki podczas wykonywania czynności pracy.

EN

In the case of workers performing occupational activities involving a risk of hand cutting and puncturing a firm grip as well as proper touch sensitivity of hands are important. Inappropriately selected ergonomic gloves can adversely influence comfort associated with lowered precision, tactile sensation, grip strength and dexterity, which, by increased muscle strain, can increase the rate of accidents at work. The aim of this study was to assess the load of the upper limb muscles during the use of selected variants of gloves protecting against slashing and puncture with hand knives. Gloves were selected depending on work task activities performed during cutting of meat. Muscle load was tested during two standard tests (cylinder strength test according to PN-EN 1082-2:2002 and Purdue Pegboard manipulation test) and three tests prepared for proper work tasks during using protective gloves. The use of gloves does not significantly affect muscle load but it had a very big impact on the tests results. Reduction of the parameters determining the efficiency of the upper limb reaches up to 250% thus more than twofold. Therefore, in order to ensure safe working conditions for cutting of meat decreased hand precision and dexterity should be taken into account when performing work tasks.

8

Biomechanical study of the influence of the weight of equipment on selected trunk muscles

100%

Schulze C. , Lindner T. , Woitge S. , Glass A. , Fimze S. , Mittelmeier W. , Bader R.

Acta of Bioengineering and Biomechanics

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2013

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tom Vol. 15, no. 3

45--51

EN

Overexertion and pain of the musculoskeletal system may occur partly owing to load application by the equipment. Both the weight of equipment and the duration of loading are relevant. The aim of the present study was to examine the extent of loading and resultant strain in the trunk muscles. Therefore, the trunk posture of soldiers and muscular activity in reaction to different equipment components (helmet, load-carrying equipment, gun and backpack) were evaluated. Electromyography was performed and a visual assessment of body axis was conducted based on standardised planar images. Data indicate that the activity of the trunk muscles examined (latissimus dorsi, trapezius and pectoralis major) is dependent on the weight and distribution of the equipment components. Activity in the trapezius muscle, for instance, was doubled during specific load application. Moreover, the method of carrying the rifle had a significant influence on the activity of the trapezius muscle (one-sided decrease of activity by 50%). Subjects were able to stabilise the body axis in the coronal plane through increased muscle activity, however, in the sagittal plane a compensatory ventral inclination of the body was observed. Uneven load distribution can lead to an irregular strain on the musculoskeletal system.

9

Individual Variation of Bowstring Release in High Level Archery: A Comparative Case Study

94%

Ertan H. , Knicker A. , Soylu R. , Strüder H.

Human Movement

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2011

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tom 12

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nr 3

273-276

EN

Purpose. The muscle-contraction strategy between the predominant forearm and pull finger used in archery is defined as a response to the fall of the "clicker" by active contraction of the m. extensor digitorum (MED) and the gradual relaxation of the m. flexor digitorum superficialis (MFDS). However, one archer with a long-term high performance history makes use of an entirely different strategy, which is thought to have positive effects on her performance. The purpose of this study was to make a more detailed analysis of the contraction strategy performed by this particular top-level archer and to consider the advantages this strategy may have on bowstring behaviour after release. Methods. A high level (world-class) archer volunteered to participate in this study. The subject has been ranked in the top 20 in the world and as one of the top 3 archers in Europe for almost two decades. The subject has a personal best score of 1354 points (pts) in a qualification round as well as receiving 168 pts in an 18-arrow match. The subject engaged in a single test session consisting of 12 shots. EMG activity of the MFDS and MED were quantified. Results. The subject's MFDS was found to be clearly relaxed even ~ 100 ms after the snap of the clicker was heard. The subject also showed a gradual relaxation of the MED after the snap of the clicker. Conclusion. The study results found that this different type of contraction-relaxation strategy can be used in the drawing arm with success, as it may avoid causing a lateral deflection of the bowstring.

10

External torque as a factor to modify load in abdominal curl-up exercises

94%

Rutkowska-Kucharska A. , Szpala A.

Biomedical Human Kinetics

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2015

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tom 7

|

nr 1

EN

Study aim: the aim of our study was to evaluate electromyography (EMG) activity in exercises where the load to the muscles is determined by the external torque. In a part of the exercises, we changed the value of the external force, while in the other we modified the length of the lever arm at which the force was applied. Material and methods: the study was carried out on a group of 12 subjects (21 ± 2 years, 61 ± 4.8 mass, 172 ± 5 cm height). Electromyographic activity of the rectus abdominis (RA) muscle was evaluated by recording the EMG signal. The length of the lever arm of the external force was changed by using four different positions of the upper limbs, whereas the magnitude of the external force was changed through adding the weights of 0.5, 1.0, and 1.5 kg. The data recorded were normalized with respect to EMG activity measured under maximum voluntary contraction (MVC) conditions. Results: it was found that the change of the lever arm at which the force was applied (any change in the position of the upper limbs) causes a change in EMG activity in each part of the RA muscle from ca. 50% to ca. 100% MVC (p < 0.001). Further, the change in the external load changes statistically significantly the EMG activity only in the left upper part of the RA muscle (p < 0.05). Conclusions: activity in the RA muscle that increased for longer lever arms of the external force, offers opportunities for changing the load used during the exercise in a manner that is safe for the vertebral column.

11

Time Analysis Of Muscle Activation During Basketball Free Throws

94%

Pakosz P. , Konieczny M.

Central European Journal of Sport Sciences and Medicine

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2016

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tom 15

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nr 3

63-69

EN

Objective of the study: The study assessed and compared the duration of the muscle activation in a basketball free throw, by players representing a preliminary and specialist stage of training. There was also analysed the accuracy of throws according to the stage of training, and whether individual changes in duration of activation have impact on the accuracy of free throws. Material and methods: Players from national basketball teams second and third league of the AZS Academic Sports Club of Opole University performed twenty free throws shooting to the basket during the research study. During tests, players were equipped with EMG apparatus, which registered the time of muscle activation, when subsequent free throws were performed. Arm muscle (biceps and triceps) activation time was measured from the beginning of muscle activation to the time of completion of their work, and from muscle activation to the time of reaching the rim. Results: Players of specialist stage of training, have 0,30 sec shorter average arm muscle time activation, counted from the beginning of activation to obtain the minimum value, from players of the preliminary stage of training. They also gained average 2 points better result in throw accuracy. Variability coefficient of throws duration was higher by 19.56% at players of the specialist stage of training. In the case of unforced extend duration of muscle activation, 80% of specialists and 40% players of preliminary group, don’t score the basket. Conclusions: It was observed that the basketball players of higher training experience, have lower average time of arm muscle activation. It was demonstrated that in players of the specialist stage of training, missed free throws were mostly caused by longer duration from the beginning of muscle activity to the rim, with players of the preliminary stage it was reverse.

12

Choosing the Right Body Position for Assessing Trunk Flexors and Extensors Torque Output

94%

Szpala A. , Rutkowska-Kucharska A. , Drapała J. , Brzostowski K.

Human Movement

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2011

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tom 12

|

nr 1

57-64

EN

Purpose. The sitting position is generally adopted when measuring the torques produced by flexors and extensors of the trunk. Results of such measurements are influenced by the strength of both abdominal muscles and flexors of the hip joint. In order to assess the effect of exercises used to strengthen the abdominal muscles it was necessary to find such a measuring position which engaged mainly the abdominal muscles. The objective of the study was an assessment of EMG activity of abdominal and spinal muscles during the measurements of muscle torques in the sitting position, as well as in the lying position. Basic procedures. Thirteen female students of the University School of Physical Education in Wrocław participated in the study. The methods of measuring muscle torques and surface electromyography (sEMG) were used under static conditions. The torques were measured on a multifunctional chair in the lying and sitting positions. The surface EMG electrodes were placed on the right and left hand sides of m. rectus abdominis (RA) and m. erector spinae (ES). Signals from both muscles were sampled at 1000 Hz. Main findings. The maximal torques of trunk flexors in the sitting position and in the lying position were similar: 130.6 ± 31.7 Nm and 129.8 ± 37.9 Nm, respectively. By contrast, the torque of trunk extensors was significantly larger when the measurement was carried out in the sitting position (228.1 ± 76.4 Nm) as compared with the lying position (148.8 ± 25.3 Nm). The ratio of the maximal torques of flexors and extensors of the trunk in the women examined was 0.572 in the sitting position and 0.872 in the lying position. Both RA and ES showed higher EMG activity in the lying position than in the sitting position. Conclusions. The higher EMG activity of the RA muscle in the lying position at the same values of the trunk flexors torque in both positions may suggest that in the sitting position flexors of the hip joint are more engaged than abdominal muscles. That is why, in order to assess the effects of abdominal muscles training, measurements of the trunk flexors torque should be performed in the lying position.

13

The Complex Analysis of Movement in the Evaluation of the Backward Somersault Performance

94%

Król H. , Klyszcz-Morciniec M. , Sobota G. , Nowak K.

Physical Activity Review

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2016

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tom 4

28-39

EN

Complex methodology was applied to study a movement structure in the standing back tuck somersault (SBTS). We have checked the usefulness of the multi-modular measuring system (SMART-E, BTS, Company, Italy) consisting of six infrared cameras, and the wireless module Pocket EMG, for measuring muscle bioelectric activity and force plate (AMTI, USA). Software Smart Analyser was used to create a database allowing the chosen parameters to be compared. Using a comprehensive methodology in the studies of the back somersault, performed with the landing at the same place (salto – S), allows for the presentation of the external and internal structure of the movement of this exercise.

14

Analysis of surface myoelectric signals by linear prediction method

94%

Suszyński W. , Kuniszyk-Jóźkowiak W. , Jaszczuk J. , Codello I. , Stęgierski R. , Kuczyński K.

Annales Universitatis Mariae Curie-Skłodowska. Sectio AI, Informatica

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2016

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tom Vol. 16, no. 1

62--70

EN

The article presents a proposal to use linear prediction method for a quick analysis of surface myoelectric (EMG) signals. The spectra obtained with the linear prediction (LP) and Fourier methods were compared. The LP method allows for a precise determination of the location and amplitude of the spectrum maximum and observation of changes in muscle tension and contraction phases. EMG spectra of brachial biceps during flexion and extension of the forearm by four adults were analyzed. The optimal width of the time window for the averaging of motor unit action potentials that allows for the observation of changes during contraction was established. It has been found that maximum spectrum during flexion has a significantly higher frequency and amplitude than during the extension of the forearm.

15

Anti-fatigue mats, low back pain, and electromyography: An interventional study

94%

Aghazadeh J. , Ghaderi M. , Azghani M.-R. , Khalkhali H.-R. , Allahyari T. , Mohebbi I.

International Journal of Occupational Medicine and Environmental Health

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2015

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tom 28

|

nr 2

347-356

EN

Objectives Increasing bilateral gluteus medius co-activation has been identified as one of the most important factors in developing low back pain due to prolonged standing in healthy people. This study aims to investigate the impact of an anti-fatigue mat on the bilateral gluteus medius co-activation pattern and to report the low back pain subjectively in 2 different standing positions on the normal rigid surface and on the anti-fatigue mat. Material and Methods While carrying out an easy simulated profession, 16 participants who had no low back pain background were requested to stand for 2 h in each position, with and without using the anti-fatigue floor mat, respectively. At the beginning of standing process and at every 15 min until the time of 120 min lapses, electric activities for the bilateral gluteus medius co-activation and subjective pain level in low back area were collected by the surface electromyogeraphy (EMG) and the visual analogue scale (VAS), respectively in each position. Results The obtained findings revealed that the anti-fatigue mat significantly decreased subjective pain level in low back area among 15 participants (p < 0.05). However, there was objectively no significant difference in the bilateral gluteus medius co-activation pattern among the participants between the position 1 and the position 2 (p > 0.05). The findings obtained under this study related to the impact of the anti-fatigue mat upon the low back pain based on the increase of > 10 mm on the VAS threshold, which showed that this intervention had no significant impact upon decreasing the number of patients suffering from the low back pain and also minimizing the bilateral gluteus medius co-activation in both pain developer groups (p > 0.05). However, 73% of the participants preferred to apply it. Conclusions It seems that the anti-fatigue mat may be useful in reducing the low back pain although it objectively didn’t significantly change the gluteus medius co-activation pattern related to the low back pain.

16

The Influence of Fatigue on Muscle Temperature

94%

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

International Journal of Occupational Safety and Ergonomics

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2012

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tom 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.

17

Analysis of muscle activity during rowing stroke phases

94%

Czajkowska U. , Świątek-Najwer E. , Jankowski L.

Acta of Bioengineering and Biomechanics

|

2023

|

tom Vol. 25, no. 1

117--126

EN

Rowing engages large muscle groups and electromyography (EMG) analysis is used to assess athletes’ condition and refine sports technique. The aim of the experiment was to evaluate the muscle activation level during different phases of the rowing cycle on an ergometer. Methods: In a study involving one professional and five amateurs, the mean EMG amplitudes from the quadriceps, gastrocnemius, biceps and triceps brachii were analyzed during different phases of rowing. A comparison was made between the degree of muscle engagement during the exercise between the professional and inexperienced individuals as well as among the different individuals during recordings obtained at different rowing speeds. The correlation coefficient between the values recorded using a strain gauge and the EMG amplitude recorded from the surface of the biceps and triceps brachii muscles was evaluated. Results: The muscle activation pattern during rowing has a predictable character. A difference in the muscle activation pattern during rowing between the professionals and amateurs was observed. The EMG signal is correlated with the force recorded by the resistive strain gauge only in the experienced rower at stroke rates 20 and 25 [1/min]. Conclusions: Electromyographic analysis can be useful for assessing the correctness of rowing techniques. The activation pattern of muscles during rowing has a predictable nature. The force generated by the participants increases with an increase in rowing frequency.

18

A Comparison of Muscular Activity Involved in the Use of Two Different Types of Computer Mouse

94%

Kumar R. , Kumar S.

International Journal of Occupational Safety and Ergonomics

|

2008

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tom Vol. 14, No. 3

305--311

EN

Two types of computer input devices, a conventional mouse and a roller bar one, were studied in terms of muscular activitiy in m. trapezius dexter, m. deltoideus anterior dexter and m. extensor digitorum dexter, and comfort rating. Fifteen university students and employees participated in this study. The order of the devices was random. While a task was performed, electromyography (EMG) data were recorded for each test. Muscular activity was found to be significantly lower for the roller bar mouse than for the conventional one. Comfort rating indicated there was a significant difference in moving a cursor with the conventional mouse compared to the roller bar one. It is concluded that a roller bar mouse allowed the subjects to work closer to the body compared to the conventional one, thus the former can be recommended as a general means of reducing upper extremity musculoskeletal disorders.

19

Sponteous facial mimicry, liking and emotional contagion

94%

McIntosh D.

Polish Psychological Bulletin

|

2006

|

tom 37

|

nr 1

31-42

EN

Facial mimicry is a basic facet of social interaction, theorized to influence emotional contagion, rapport, and perception and interpretation of others' emotional facial expressions. Using EMG, two studies examined spontaneous mimicry of emotional facial expressions of live models over time, and whether the relationship between the model and observer moderated mimicry. Study 1 manipulated observers' liking of a confederate model; Study 2 compared friends with strangers. Observers mimicked brow and cheek movement. Observers who liked the models mimicked cheek movements more than those who did not like them. Study 2 demonstrated mimicry of natural, spontaneous expressions and found that observers' affect changed in association with the models'. People mimic live, dynamic facial expressions, likely more idiosyncratic and weaker than prototypes often used as stimuli, supporting the naturalistic importance of mimicry. Liking increases mimicry of smiles, indicating that mimicry is partially a consequence, not just a cause, of positive social relationships.

20

The comparative gait effects of select walking surfaces using kinetic and EMG analyses

94%

Slaughter S. , Butler P. , Capozzella H. , Nguyen A. , Hutcheson L.

Human Movement

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2012

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tom 13

|

nr 3

198-203

EN

Purpose. This study investigated the EMG characteristics of muscles crossing the knee and the kinetics of the lower extremity during side-slope walking and other activities of daily living. We studied the difference in EMG data of the medial gastrocnemius and vastus lateralis muscles bilaterally and the relative rotation of the thigh to leg. Methods. Eleven outdoor workers (47.3 ± 13.9 years old) were recruited for this study. Participants walked on a 0° flat surface, 5° and 10° side-sloped surfaces, 10° inclined treadmill and ascended stairs. The EMG activity and rotation about a vertical axis during stance phase were analyzed. Results. Except for minor variations, ANOVA showed no significant difference in EMG activity between the walking surfaces, furthermore, the relative rotation of thigh-to-leg showed little or no differences between the variables. Multivariate ANOVA showed p-values between 0.1602 and 0.9943 when comparing the EMG data of all side-sloped surfaces. The relative rotation of the thigh to the leg showed p-values of 0.7837 and 0.9813 when comparing the left 0° to 10° and right 0° to 10°, respectively. Conclusions. The results of this study indirectly indicate that when considering rotation about a vertical axis and EMG activity, there is little difference in knee joint loading.