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1

A foot joint and muscle force assessment of the running stance phase whilst wearing normal shoes and bionic shoes

Zhou Huiyu, Xu Datao, Quan Wenjing, Ugbolue Ukadike Chris, Sculthorpe Nicholas F., Baker Julien S., Gu Yaodong

Acta of Bioengineering and Biomechanics

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2022

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Vol. 24, no. 1

191--202

EN

The aim of this study was to investigate the differences in ankle joint parameters of biomechanics changes between the normal shoes (NS) and the bionic shoes (BS) during the running stance phases. Methods: A total of 40 Chinese male runners from Ningbo University were recruited for this study (age: 22.3 ± 3.01 years; height: 174.67 ± 7.11 cm; body weight (BW): 66.83 ± 9.91 kg). The participants were asked to perform a running task. Statistical parametric mapping (SPM) analysis was used to investigate any differences between NS and BS during the running stance phases. The principal component analysis (PCA) and support vector machine (SVM) were used to further explore the differences of the muscle force between the BS and NS. Results: Significant differences ( p < 0.05) were found in the first metatarsophalangeal joint (MPJ1), ground reaction force (GRF), ankle joint and around muscle forces. Furthermore, the accuracy of SVM model in identifying the gait muscle force between BS and NS reached 100%, which proved that the BS had a very large impact on the gait muscle force compared with NS. Conclusions: We found that BS may be better suited to the human condition than other unstable shoes, or even NS. In addition, our results suggest that BS play an important role in reducing ankle injuries during running by increasing muscle participation in unstable conditions while better restoring the most primitive instability of foot condition that humans have.

2

Joint loads and muscle force distribution during classical and jazz pirouettes

Błażkiewicz Michalina

Acta of Bioengineering and Biomechanics

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2021

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Vol. 23, no. 1

3--13

EN

Purpose: The objective of this study was to analyze the muscle force distribution and lower limb joint loading during two types of pirouettes and check which muscle in which pirouette generates the highest force and which joint is the most loaded. Methods: Skilled dancers (n = 16) performed single-turn pirouettes in jazz and classic styles. Kinematic and kinetic data were collected using the Vicon system and Kistler plates. The joint reaction forces and muscle forces were calculated using a musculoskeletal model in the AnyBody Modeling System. Results: No statistically significant differences were found for the duration of the turn in both pirouettes. The range of motion in all joints of supporting leg in sagittal plane and in hip joint in frontal plane for non-supporting leg were significantly higher in classic pirouette. The ankle joint was the most loaded joint in both pirouettes and its maximal value was significantly higher in classic pirouette. The force generated by ankle plantar flexors muscles was significantly greater in the jazz pirouette in turn phase. For the nonsupport limb, external hip rotators generated significantly greater force when performing the classic pirouette. Conclusions: It seems that early stage dancers may start their lessons with jazz pirouettes, where necessary joint mobility is lesser. They also are supposed to increase muscle strength and body awareness with such proceedings. A better awareness of the mechanical loads on the musculoskeletal system which a dancer performing pirouettes faces should have an impact on the way dance classes are conducted and choreographic elements are sequenced.

3

Evaluation of the effect of muscle forces implementation on the behavior of a dummy during a head-on collision

Sybilski Kamil, Mazurkiewicz Łukasz, Jurkojć Jacek, Michnik Robert, Małachowski Jerzy

Acta of Bioengineering and Biomechanics

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2021

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Vol. 23, no. 4

137--147

EN

Purpose: The aim of this study was to develop a method to implement muscle forces to a numerical model of a dummy and to evaluate the effect of muscle activation on driver behavior during a frontal collision. The authors focused on the forces acting at the knee, hip, and elbow joints. Methods: The authors carried out torque measurements in joints using the Biodex System 4. Then, the previously developed numerical models were modified by introducing the joint torque values. Moments of force were introduced as a function of the rotation angle. During research, numerical simulations were carried out in three stages: in the first stage, a full vehicle crash was analyzed to determine the change of velocity of the vehicle interior; in the second stage, subsidence of the system was realized; in the third stage, a frontal crash was simulated. The models considered the operation of the sensors, airbag and seat belt tensioning system. Results: A numerical model with the active response of the dummy to the change in position during impact was developed. The results of the dynamic analysis were used to analyze the impact of muscle activation on dummy behavior. The change in shoulders rotation angle, the lateral and vertical displacement of the dummy’s center of gravity, and the forces acting between the dummy and the seat belt were compared. Conclusions: The effect of muscle action on the behavior of a dummy during a frontal collision was determined.

4

Effective utilization of man shift through sustainable workload testing for underground mining machine operators. An ergonomic based man-machine interface approach

Dey Netai Chandra, Dey Shibaji

New Trends in Production Engineering

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2019

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Vol. 2, Iss. 1

394--403

EN

Insight of man-machine interfaces during mining machine operations, better co-ordinance with human efficiencies and suitable workload selection in underground mining machine operation are the main viewpoints of the study. Total 12 side discharge loader (SDL) and load haul dumper (LHD) operators [N = 12] have been taken as participants of the study. The methodology is divided into two parts first part is devoted to measuring and analyzing workload response of machine operation with polar heart rate monitor. Machine operator’s heart rate ratio (HR ratio) for the whole shift is recorded and metabolic rate (MR) has been analyzed. Additionally, fatigue sustainability (FS) and degradation of muscle force (MF) are recorded for each work cycles up to exposure time period (ETP) of 360 minutes. In the second part of the methodology, based on the HR ratio recorded during the mining operation, a workload simulation study is undertaken on a treadmill at the surface following BRUCE protocol. At treadmill, based on HR ratio, workload achieved from mines along with three different workloads i.e. low, moderate and high has been tested. Differences in FS and degradation rate of MF after each workload experiment have been recorded. A result from the underground operational study shows that there is about 43.2% and 32.4% of decreasing MF for SDL and LHD operators after end of spells at mines. Additionally, a negative correlation (r = -0.99) is found between ETP and MF. The workload simulation study shows that there are significant differences between FS (p < 0.05) and MF (p < 0.05) data of mining and treadmill experiment with the same workload. In comparison to an underground operation, FS rate of low, moderate and high workload is recorded 60%, 35%, and 15% higher respectively than of mine workload. Higher FS rate may achieve due to availability of good environment. Among the tested workload only low kind of workload is found suitable for mining machinery job as degradation of MF is found significantly (p < 0.05) low and FS is found significantly (p < 0.01) high in this kind of workload. Therefore, it can be concluded that in mining machinery operation better to adopt low workload for effective utilization of man shift (EUMS) as it gives comparatively low MF degradation and better FS during continuous work.

5

Force analysis of shoulder joint muscles in the early phase of brain stroke

Starosta M., Kostka J., Miller E.

Acta of Bioengineering and Biomechanics

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2018

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Vol. 20, no. 3

107--113

EN

Upper limb impairment in the early phase of brain stroke is one of the key problems in rehabilitation. An estimation of muscle force can be a helpful factor for functional improvement after a stroke. The primary goals of this study were to determine the muscles with the lowest force in the affected (A) and non-affected (non-A) upper limb. Moreover, the differences between men and women were compared and these values were correlated with age. Methods: One hundred (n = 35 female, n = 65 male) post-stroke patients met the inclusion criteria. The mean age of the study participants was 66.1 years. Muscle force for external and internal rotators of shoulder was measured with handheld dynamometer. Moreover, the correlation coefficients for differences in muscular force with the patient’s age were estimated. Results: Our study reports that the force of the (A) side in relation to the (non-A) was by 37% weaker. We observed about a 40% decrease in the force of the shoulder’s external rotation (female – 42%; male – 41%) and shoulder’s flexion (by 38% – female; 40% – male). Significant correlations between the muscle force and the age of post-stroke patients were also found. It was concluded that about 4 weeks after the first stroke in the patient’s life, the external rotators are the most affected group of shoulder muscles. Conclusions: Neither sex nor the side of the ischemic brain injury influence the muscle force, whereas age determines both muscle force and muscle force deficits. Older post-stroke patients demonstrate fewer deficits in muscle strength than younger ones.

6

An application of a dynamic thermography for studying a relation between thermal and mechanical activities of a skeletal muscle during a static load

Radomski D., Kruszewski K.

Measurement Automation Monitoring

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2017

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Vol. 63, No. 4

139--142

EN

A thermal distribution provides useful information of physiological and pathological processes. However, only a static thermography was applied in the most of medical studies. This paper shows an example of application of a dynamic thermography to study a physiological activity of a skeletal muscle. The goal of the presented work was to study a putative relationship between mechanical and thermal activity of the quadriceps during a static submaximal load. During a strain a dynamic temperature distribution on a thigh surface and a force moment of a knee erector were registered. The performed analysis used a time-dependent mean temperature, a time-dependent standard deviation and an impulse of a force moment. Moreover, we analyzed of autocorrelation functions to compare the dynamics of these parameters. Finally, we showed the nonlinear, statistically significant relationship between spatial-temporal variability of temperature and the force developing by a concentrative contracted quadriceps. A possible biological interpretation of the identified relation is also proposed taking the described mathematical model of muscle heat transfer into account.

7

Characterization of the mechanomyographic signal of three different muscles and at different levels of isometric contractions

Jotta B., Garcia M. A. C., Pino A. V., Souza M. N. de

Acta of Bioengineering and Biomechanics

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2015

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Vol. 17, no. 4

73--84

EN

Purpose: Lateral (X) and longitudinal (Y) mechanical oscillations of muscle fibers that take place during muscular contraction seem to contain information additionally to the myoelectric activity, which can contribute to the interpretation of some muscle gradation force mechanisms. However, no previous study was found that had investigated the relationship between the muscle force and features associated to the mechanomyographic (MMG) signal obtained by means of a biaxial accelerometer in three different muscles. Therefore, the aim of this study was to evaluate the relationship between the force output at different load levels (20% to 100%) of the maximum voluntary isometric contraction (%MVIC) and the two signals supplied by a biaxial accelerometer and, in addition, the so-called resultant (R) acceleration signal derived from the two signals mentioned previously. Twenty seven male volunteers participated in this study. Methods: The force output related to the right biceps brachii, soleus and gastrocnemius medialis muscles was studied by means of linear regression models fit to log-transformed of the root mean square (RMS) values of the MMG signals in X, Y, and R axes versus each %MVIC. The phase angle of R acceleration (PhaseR) and anthropometric data were also considered. Results: The angular coefficient a and the antilog of y-intercept b from the log-transformed of MMG data values versus force output were able to distinguish partially motor unit strategies during isometric contractions in the three muscles studied. Conclusion: The findings suggest that biaxial accelerometer seems to be an interesting approach in the assessment of muscle contraction properties.

8

Zmiany mocy i skoczności u siatkarek w okresie przygotowawczym

Lipińska M., Michalski R.

Aktualne Problemy Biomechaniki

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2011

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z. 5

75--80

PL

Celem pracy było określenie zmian mocy kończyn dolnych i wysokości uniesienia środka masy ciała mierzonych w wyskokach CMJ i BCMJ na platformie dynamometrycznej u siatkarek w okresie przygotowawczym. W badaniach uczestniczyło 14 siatkarek. Pomiar mocy kończyn dolnych i wysokości uniesienia środka masy ciała przeprowadzono na platformie dynamometrycznej. Moc maksymalna uległa nieistotnemu zwiększeniu o 6,3% w CMJ i zmniejszeniu o 4,1% w BCMJ podczas gdy wysokość uniesienia środka masy ciała nie uległa zmianie w CMJ i zwiększyła się istotnie o 4,7% w BCMJ.

EN

The aim of this study was to determine the changes of power of lower limbs and height of rise of the body mass center at CMJ and BCMJ jumps on the dynamometric platform of female volleyball players during preparatory period. Fourteen female volleyball players took part in this study. The measurement of lower limb power and height of rise of the body mass center was carried out on a dynamometric platform. Maximal power has nonsignificantly increased by 6.3% in CMJ, and decreased by 4.1% in BCMJ while height of rise of the body mass centre did not change in the CMJ and increased significantly by 4.7% in BCMJ.

9

Objective measurements of muscle force in a group of after-stroke patients with hemiparesis

Pasternak-Miłądzka I., Miłądzki Z., Będziński R., Baran B.

Acta of Bioengineering and Biomechanics

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2007

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Vol. 9, nr 1

19-23

EN

The aim of this study was to estimate the strength of spastic muscles using Biodex System 3 within a group of patients with hemiparesis in after-stroke population. Measurements of the moments of force in elbow flexors and extensors of both spastic and non-spastic limbs were conducted under isostatic conditions. We analysed the values obtained for both limbs in order to determine the spasticity level on an Ashworth scale (0–4). The subjects were 10 patients with hemiparesis and varying spasticity selected from an after-stroke population. The analysis showed that spastic muscles activated less force than non-spastic muscles of the same patient. Furthermore, in a spastic limb, higher values of force were noted in the flexors than in the extensors of the elbow. In a non-spastic limb, the values of force were higher in the extensors of the elbow joint than in flexors. It is worth adding that the dynamics of force exposure, defined by a gradient of force, was much lower in spastic muscles than in non-spastic ones. Objective estimation of muscle force can be done by measuring the moments of force in particular groups of muscles upon the isokinetic contraction appearing. The repeatability of measurements may enable the kind of kinesitherapy to be determined as well as the assessment of the effectiveness of exercises in regard to force increase and dynamics of spastic muscles.

10

Evaluation of exercise duration on muscle forces

Jurkojć J., Michnik R., Skiba O.

Zeszyty Naukowe Katedry Mechaniki Stosowanej / Politechnika Śląska

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2005

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z. 28

63-66

EN

Methodology of experimental investigation into fatigue of muscles as well as results obtained during research are presented in the paper. Measurements were carried out on a rehabilitation chair that enables taking measurements of moment of muscle forces during isometric flexion and extension.

11

Electromyographic Analysis of a Repetitive Hand Gripping Task

Cook T., Rosecrance J., Zimmermann C., Gerleman D., Ludewig P.

International Journal of Occupational Safety and Ergonomics

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1998

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Vol. 4, No. 2

185--198

EN

Electromyography (EMG) has been proposed as a method for determining muscle effort in repetitive upper limb tasks, which are often related to cumulative trauma disorders. EMG activity of the finger flexor musculature was investigated during a repetitive hand gripping task having 5 different cycle durations (2 to 6 s), various percentage of work time (and rest) within the work cycle (20% to 80%), and 3 different grip force levels. Thirty healthy adult participants each performed 27 randomly ordered 30-s repetitive hand gripping trials as well as 3 isometric contractions, which were used to normalize data from the hand gripping trials. There was a significant decrease in mean EMG as the duration of the work-rest cycle time increased. At each force level, EMG increased as the percentage of work time within the work-rest cycle increased, but to a greater extent at the highest force level. The results of this study suggest that overall muscle effort, and perhaps muscle fatigue, can be reduced most effectively by modifying the force requirements of the repetitive task. Other variables, such as the percentage of work time within a cycle and overall work cycle time have less effect on the EMG activity level. The results of this study have implications for developing strategies to reduce muscle fatigue during repetitive hand gripping tasks in an effort to reduce the effects of cumulative trauma disorders.