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Uwamahoro R, Sundaraj K, Feroz FS. Effect of Forearm Postures and Elbow Joint Angles on Elbow Flexion Torque and Mechanomyography in Neuromuscular Electrical Stimulation of the Biceps Brachii. SENSORS (BASEL, SWITZERLAND) 2023; 23:8165. [PMID: 37836995 PMCID: PMC10575078 DOI: 10.3390/s23198165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Revised: 08/31/2023] [Accepted: 09/05/2023] [Indexed: 10/15/2023]
Abstract
Neuromuscular electrical stimulation plays a pivotal role in rehabilitating muscle function among individuals with neurological impairment. However, there remains uncertainty regarding whether the muscle's response to electrical excitation is affected by forearm posture, joint angle, or a combination of both factors. This study aimed to investigate the effects of forearm postures and elbow joint angles on the muscle torque and MMG signals. Measurements of the torque around the elbow and MMG of the biceps brachii (BB) muscle were conducted in 36 healthy subjects (age, 22.24 ± 2.94 years; height, 172 ± 0.5 cm; and weight, 67.01 ± 7.22 kg) using an in-house elbow flexion testbed and neuromuscular electrical stimulation (NMES) of the BB muscle. The BB muscle was stimulated while the forearm was positioned in the neutral, pronation, or supination positions. The elbow was flexed at angles of 10°, 30°, 60°, and 90°. The study analyzed the impact of the forearm posture(s) and elbow joint angle(s) on the root-mean-square value of the torque (TQRMS). Subsequently, various MMG parameters, such as the root-mean-square value (MMGRMS), the mean power frequency (MMGMPF), and the median frequency (MMGMDF), were analyzed along the longitudinal, lateral, and transverse axes of the BB muscle fibers. The test-retest interclass correlation coefficient (ICC21) for the torque and MMG ranged from 0.522 to 0.828. Repeated-measure ANOVAs showed that the forearm posture and elbow flexion angle significantly influenced the TQRMS (p < 0.05). Similarly, the MMGRMS, MMGMPF, and MMGMDF showed significant differences among all the postures and angles (p < 0.05). However, the combined main effect of the forearm posture and elbow joint angle was insignificant along the longitudinal axis (p > 0.05). The study also found that the MMGRMS and TQRMS increased with increases in the joint angle from 10° to 60° and decreased at greater angles. However, during this investigation, the MMGMPF and MMGMDF exhibited a consistent decrease in response to increases in the joint angle for the lateral and transverse axes of the BB muscle. These findings suggest that the muscle contraction evoked by NMES may be influenced by the interplay between actin and myosin filaments, which are responsible for muscle contraction and are, in turn, influenced by the muscle length. Because restoring the function of limbs is a common goal in rehabilitation services, the use of MMG in the development of methods that may enable the real-time tracking of exact muscle dimensional changes and activation levels is imperative.
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Affiliation(s)
- Raphael Uwamahoro
- Fakulti Kejuruteraan Elektronik dan Kejuruteraan Komputer, Universiti Teknikal Malaysia Melaka, Durian Tunggal 76100, Melaka, Malaysia; (R.U.); (F.S.F.)
- Regional Centre of Excellence in Biomedical Engineering and e-Health, University of Rwanda, Kigali P.O. Box 4285, Rwanda
| | - Kenneth Sundaraj
- Fakulti Kejuruteraan Elektronik dan Kejuruteraan Komputer, Universiti Teknikal Malaysia Melaka, Durian Tunggal 76100, Melaka, Malaysia; (R.U.); (F.S.F.)
| | - Farah Shahnaz Feroz
- Fakulti Kejuruteraan Elektronik dan Kejuruteraan Komputer, Universiti Teknikal Malaysia Melaka, Durian Tunggal 76100, Melaka, Malaysia; (R.U.); (F.S.F.)
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Shi F, Rymer WZ, Son J. Mechanomyogram amplitude vs. isometric ankle plantarflexion torque of human medial gastrocnemius muscle at different ankle joint angles. J Electromyogr Kinesiol 2021; 61:102609. [PMID: 34689116 DOI: 10.1016/j.jelekin.2021.102609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 09/23/2021] [Accepted: 10/07/2021] [Indexed: 10/20/2022] Open
Abstract
The purpose of this study was to investigate the influence of changes in ankle joint angle on the mechanomyogram (MMG) amplitude of the human medial gastrocnemius (MG) muscle during voluntary isometric plantarflexion contractions. Ten healthy individuals were asked to perform voluntary isometric contractions at six different contraction intensities (from 10% to 100%) and at three different ankle joint angles (plantarflexion of 26°; plantarflexion of 10°; dorsiflexion of 3°). MMG signals were recorded from the surface over the MG muscle, using a 3-axis accelerometer. The relations between root mean square (RMS) MMG and isometric plantarflexion torque at different ankle joint angles were characterized to evaluate the effects of altered muscle mechanical properties on RMS MMG. We found that the relation between RMS MMG and plantarflexion torque is changed at different ankle joint angles: RMS MMG increases monotonically with increasing the plantarflexion torque but decreases as the ankle joint became dorsiflexed. Moreover, RMS MMG shows a negative correlation with muscle length, with passive torque, and with maximum voluntary torque, which were all changed significantly at different ankle joint angles. Our findings demonstrate the potential effects of changing muscle mechanical properties on muscle vibration amplitude. Future studies are required to explore the major sources of this muscle vibration from the perspective of muscle mechanics and muscle activation level, attributable to changes in the neural command.
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Affiliation(s)
- Fandi Shi
- Department of Biomedical Engineering, McCormick School of Engineering, Northwestern University, Evanston, IL, United States; Shirley Ryan AbilityLab (formerly the Rehabilitation Institute of Chicago), Chicago, IL, United States
| | - William Zev Rymer
- Department of Biomedical Engineering, McCormick School of Engineering, Northwestern University, Evanston, IL, United States; Shirley Ryan AbilityLab (formerly the Rehabilitation Institute of Chicago), Chicago, IL, United States; Department of Physical Medicine and Rehabilitation, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
| | - Jongsang Son
- Shirley Ryan AbilityLab (formerly the Rehabilitation Institute of Chicago), Chicago, IL, United States; Department of Physical Medicine and Rehabilitation, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States.
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Krueger E, Scheeren EM, Nogueira-Neto GN, Button VLDSN, Nohama P. Advances and perspectives of mechanomyography. ACTA ACUST UNITED AC 2014. [DOI: 10.1590/1517-3151.0541] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Eddy Krueger
- Universidade Tecnológica Federal do Paraná - UTFPR, Brasil
| | | | | | | | - Percy Nohama
- Universidade Tecnológica Federal do Paraná - UTFPR, Brasil; Pontifícia Universidade Católica do Paraná - PUCPR, Brasil; Universidade Estadual de Campinas - UNICAMP, Brasil
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Laser-detected lateral muscle displacement is correlated with force fluctuations during voluntary contractions in humans. J Neurosci Methods 2008; 173:271-8. [PMID: 18644407 DOI: 10.1016/j.jneumeth.2008.06.022] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2008] [Revised: 06/20/2008] [Accepted: 06/20/2008] [Indexed: 11/23/2022]
Abstract
Fluctuations in muscle force during steady voluntary contractions result from the summation of twitch forces produced by asynchronous activation of multiple motor units. We hypothesized that oscillatory lateral muscle displacement, measured with a non-contact high-resolution laser displacement sensor, is correlated with force fluctuations during steady, voluntary contractions with a human muscle. Eight healthy young adults (20-33 yrs) performed steady isometric contractions with the first dorsal interosseus muscle. Contraction intensity ranged from 2.5% to 60% of the maximal voluntary contraction force. Oscillatory lateral displacement of the muscle surface was measured with a high-resolution laser displacement sensor (0.5 microm resolution), concurrently with abduction force of the index finger. In the time-domain analysis, there was a significant positive peak in the cross-correlation function between lateral muscle displacement and force fluctuations. In addition, the amplitude increased linearly with contraction intensity in both signals. In the frequency-domain analysis, frequency content was similar in both signals, and there was significant coherence between signals for the major frequency range of the signals (<5 Hz). In conclusion, laser-detected lateral displacement of a hand muscle is correlated with force fluctuations across a wide range of contraction intensity during steady voluntary contractions in humans.
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Jaskólski A, Andrzejewska R, Marusiak J, Kisiel-Sajewicz K, Jaskólska A. Similar response of agonist and antagonist muscles after eccentric exercise revealed by electromyography and mechanomyography. J Electromyogr Kinesiol 2007; 17:568-77. [PMID: 16890456 DOI: 10.1016/j.jelekin.2006.05.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2006] [Revised: 05/18/2006] [Accepted: 05/31/2006] [Indexed: 11/21/2022] Open
Abstract
The purpose of this study was to investigate the influence of eccentric contractions (ECC) on the biceps (BB) and triceps brachii (TB) muscles during maximal voluntary contraction (MVC) of elbow flexors using electrical (EMG) and mechanomyographical activities (MMG). Each of 18 male students performed 25 submaximal contractions (50% MVC) of the elbow flexors. Root mean square amplitude (RMS) and median frequency (MDF) were calculated for the EMG and MMG signals recorded during MVC. All measurements were taken before, immediately after, 24, 48, 72, and 120 h post-ECC from the BB and TB muscles. MVC was reduced by 34% immediately after exercise and did not return to the resting value within 120 h (P0.05). The EMG MDF decreased significantly (P< or =0.05) in both muscles after ECC. The MMG RMS at 24h, 48, 72 and 120 h post-ECC was significantly lower compared to that recorded immediately after ECC in both muscles (P< or =0.05). The present research showed that (i) there were similar changes in electrical and mechanical activities during MVC after submaximal ECC in agonist and antagonist muscles suggesting a common drive controlling the agonist and antagonist motoneuron pool, (ii) the ECC induced different changes in EMG than in MMG immediately after ECC and during 120 h of recovery that suggested an increased tremor and contractile impairments, i.e., reduced rate of calcium release from the sarcoplasmic reticulum (acute effect), and changes in motor control mechanisms of agonist and antagonist muscles, and increased muscle stiffness (chronic effect).
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Affiliation(s)
- Artur Jaskólski
- Department of Kinesiology, University School of Physical Education, ul. Rzeźbiarska 4, 51-629 Wrocław, Poland.
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Beck TW, Housh TJ, Johnson GO, Cramer JT, Weir JP, Coburn JW, Malek MH. Does the frequency content of the surface mechanomyographic signal reflect motor unit firing rates? A brief review. J Electromyogr Kinesiol 2006; 17:1-13. [PMID: 16497517 DOI: 10.1016/j.jelekin.2005.12.002] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2005] [Revised: 12/08/2005] [Accepted: 12/18/2005] [Indexed: 11/29/2022] Open
Abstract
The purpose of this review is to examine the literature that has investigated the potential relationship between mechanomyographic (MMG) frequency and motor unit firing rates. Several different experimental designs/methodologies have been used to address this issue, including: repetitive electrical stimulation, voluntary muscle actions in muscles with different fiber type compositions, fatiguing and non-fatiguing isometric or dynamic muscle actions, and voluntary muscle actions in young versus elderly subjects and healthy individuals versus subjects with a neuromuscular disease(s). Generally speaking, the results from these investigations have suggested that MMG frequency is related to the rate of motor unit activation and the contractile properties (contraction and relaxation times) of the muscle fibers. Other studies, however, have reported that MMG mean power frequency (MPF) does not always follow the expected pattern of firing rate modulation (e.g. motor unit firing rates generally increase with torque during isometric muscle actions, but MMG MPF may remain stable or even decrease). In addition, there are several factors that may affect the frequency content of the MMG signal during a voluntary muscle action (i.e. muscle stiffness, intramuscular fluid pressure, etc.), independent of changes in motor unit firing rates. Despite the potential influences of these factors, most of the evidence has suggested that the frequency domain of the MMG signal contains some information regarding motor unit firing rates. It is likely, however, that this information is qualitative, rather than quantitative in nature, and reflects the global motor unit firing rate, rather than the firing rates of a particular group of motor units.
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Affiliation(s)
- Travis W Beck
- Department of Nutrition and Health Sciences, Human Performance Laboratory, University of Nebraska-Lincoln, 104K Ruth Leverton Hall, Lincoln, NE 68583-0806, United States.
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Beck TW, Housh TJ, Cramer JT, Weir JP, Johnson GO, Coburn JW, Malek MH, Mielke M. Mechanomyographic amplitude and frequency responses during dynamic muscle actions: a comprehensive review. Biomed Eng Online 2005; 4:67. [PMID: 16364182 PMCID: PMC1343566 DOI: 10.1186/1475-925x-4-67] [Citation(s) in RCA: 109] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2005] [Accepted: 12/19/2005] [Indexed: 11/21/2022] Open
Abstract
The purpose of this review is to examine the literature that has investigated mechanomyographic (MMG) amplitude and frequency responses during dynamic muscle actions. To date, the majority of MMG research has focused on isometric muscle actions. Recent studies, however, have examined the MMG time and/or frequency domain responses during various types of dynamic activities, including dynamic constant external resistance (DCER) and isokinetic muscle actions, as well as cycle ergometry. Despite the potential influences of factors such as changes in muscle length and the thickness of the tissue between the muscle and the MMG sensor, there is convincing evidence that during dynamic muscle actions, the MMG signal provides valid information regarding muscle function. This argument is supported by consistencies in the MMG literature, such as the close relationship between MMG amplitude and power output and a linear increase in MMG amplitude with concentric torque production. There are still many issues, however, that have yet to be resolved, and the literature base for MMG during both dynamic and isometric muscle actions is far from complete. Thus, it is important to investigate the unique applications of MMG amplitude and frequency responses with different experimental designs/methodologies to continually reassess the uses/limitations of MMG.
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Affiliation(s)
- Travis W Beck
- Department of Nutrition and Health Sciences, Human Performance Laboratory, University of Nebraska-Lincoln, Lincoln, NE, USA 68583
| | - Terry J Housh
- Department of Nutrition and Health Sciences, Human Performance Laboratory, University of Nebraska-Lincoln, Lincoln, NE, USA 68583
| | - Joel T Cramer
- Department of Health and Exercise Science, University of Oklahoma, Norman, OK, USA 73019
| | - Joseph P Weir
- Applied Physiology Laboratory, Division of Physical Therapy, Des Moines University, Osteopathic Medical Center, Des Moines, IA, USA 50312
| | - Glen O Johnson
- Department of Nutrition and Health Sciences, Human Performance Laboratory, University of Nebraska-Lincoln, Lincoln, NE, USA 68583
| | - Jared W Coburn
- Department of Kinesiology, California State University, Fullerton, Fullerton, CA, USA 92834
| | - Moh H Malek
- Department of Nutrition and Health Sciences, Human Performance Laboratory, University of Nebraska-Lincoln, Lincoln, NE, USA 68583
| | - Michelle Mielke
- Department of Nutrition and Health Sciences, Human Performance Laboratory, University of Nebraska-Lincoln, Lincoln, NE, USA 68583
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Orizio C, Gobbo M, Veicsteinas A, Baratta RV, Zhou BH, Solomonow M. Transients of the force and surface mechanomyogram during cat gastrocnemius tetanic stimulation. Eur J Appl Physiol 2003; 88:601-6. [PMID: 12560961 DOI: 10.1007/s00421-002-0765-3] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/22/2002] [Indexed: 11/30/2022]
Abstract
The aim of the study was to investigate the time relationship between force and muscle surface displacement, detected as the surface mechanomyogram (MMG) by a laser distance sensor, in the transient phases of a tetanic stimulation. For this purpose the motor nerve of the exposed medial gastrocnemius of four cats was supramaximally stimulated at 30, 40 and 50 Hz for 9 s. Force was detected by a transducer connected at the distal tendon while MMG was measured after pointing the laser beam at the muscle belly. We found that the MMG always anticipated and trailed the force changes during the on- and off-phase of the tetani, respectively. Independently of the stimulation rate, the half-times of the two signals were: on-phase, about 76 ms for force and 33 ms for MMG; off-phase, about 83 ms for force and 132 ms for MMG. There are two main comments to make about these results. First, during the on-phase the shortening of the contractile elements results at first in a muscle geometry change with low output force. After this, when the slack of the elastic-connective tissue has been taken up, the tension is efficiently transmitted to the tendon. Second, the different force and MMG dynamics in the on- and off-phases determine a counter-clockwise hysteresis with more force produced at a given muscle surface displacement during relaxation. To explain the results, the possible specific roles of some components of the muscle mechanical model, muscle mechanical properties and intra-muscular phenomena taking place during contraction have been discussed.
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Affiliation(s)
- Claudio Orizio
- Dipartimento di Scienze Biomediche e Biotecnologie, Università degli Studi di Brescia, Via Valsabbina 19, Italy.
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Yoshitake Y, Shinohara M, Ue H, Moritani T. Characteristics of surface mechanomyogram are dependent on development of fusion of motor units in humans. J Appl Physiol (1985) 2002; 93:1744-52. [PMID: 12381762 DOI: 10.1152/japplphysiol.00008.2002] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The purpose of this study was to test whether surface mechanomyogram (MMG) recorded on the skin reflects the contractile properties of individual motor units in humans. Eight motor units in the medial gastrocnemius muscle were identified, and trains of stimulation at 5, 10, 15, and 20 Hz were delivered to each isolated motor unit. There was a significant positive correlation between the duration of MMG and twitch duration. MMG amplitude decreased with increasing stimulation frequency. Reductions in MMG amplitude were in parallel with the reductions in force fluctuations, and the rate of change in both was positively correlated across the motor units. Rate of change in MMG amplitude against force was negatively correlated to half relaxation time and twitch duration. Similar negative correlations were found between force fluctuations and contractile properties. These results provide evidence supporting a direct relation between MMG and contractile properties of individual motor units within the gastrocnemius muscle, indicating that surface MMG is dependent on the contractile properties of the activated motor units in humans.
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Affiliation(s)
- Yasuhide Yoshitake
- Laboratory of Applied Physiology, Graduate School of Human and Environmental Studies, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan.
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Mamaghani NK, Shimomura Y, Iwanaga K, Katsuura T. Mechanomyogram and electromyogram responses of upper limb during sustained isometric fatigue with varying shoulder and elbow postures. JOURNAL OF PHYSIOLOGICAL ANTHROPOLOGY AND APPLIED HUMAN SCIENCE 2002; 21:29-43. [PMID: 11938607 DOI: 10.2114/jpa.21.29] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
To investigate the behavior of mechanomyogram (MMG) and electromyogram (EMG) signals in the time and frequency domains during sustained isometric contraction, MMG and surface EMG were obtained simultaneously from four muscles: upper trapezius (TP), anterior deltoid (DL), biceps brachii (BB), and brachioradialis (BR) of 10 healthy male subjects. Experimental conditions consisted of 27 combinations of 9 postures [3 shoulder angles (SA): 0 degree, 30 degrees, 60 degrees and 3 elbow angles (EA): 120 degrees, 90 degrees, 60 degrees] and 3 contraction levels: 20%, 40%, and 60% of maximum voluntary contraction (MVC). Subjective evaluations of fatigue were also assessed using the Borg scale at intervals of 60, 30, and 10 sec at 20%, 40%, and 60% MVC tests, respectively. The mean power frequency (MPF) and root mean square (RMS) of both signals were calculated. The current study found clear and significant relationships among physiological and psychological parameters on the one hand and SA and EA on the other. EA's effect on MVC was found to be significant. SA had a highly significant effect on both endurance time and Borg scale. In all experimental conditions, significant correlations were found between the changes in MPF and RMS of EMG in BB with SA and EA (or muscle length). In all four muscles, MMG frequency content was two or three times lower than EMG frequency content. During sustained isometric contraction, the EMG signal showed the well-known shift to lower frequencies (a continuous decrease from onset to completion of the contraction). In contrast, the MMG spectra did not show any shift, although its form changed (generally remaining about constant). Throughout the contraction, increased RMS of EMG was found for all tests, whereas in the MMG signal, a significant progressive increase in RMS was observed only at 20% MVC in all four muscles. This supports the hypothesis that the RMS amplitude of the MMG signal produced during contraction is highly correlated with force production. Possible explanations for this behavioral difference between the MMG and EMG signals are discussed.
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Yoshitake Y, Moritani T. The muscle sound properties of different muscle fiber types during voluntary and electrically induced contractions. J Electromyogr Kinesiol 1999; 9:209-17. [PMID: 10328416 DOI: 10.1016/s1050-6411(98)00035-2] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Soundmyogram (SMG) and electromyogram signals were recorded simultaneously from the relatively fast medial gastrocnemius (MG) and slow soleus (SOL) during voluntary and electrically induced contractions. Using a spike-triggered averaging technique, the averaged elementary sound and corresponding MU spikes were also obtained from about 35 different MUs identified. The rms-SMG of MG increased as a function of force (P < 0.01). On the contrary, these values for SOL increased up to 60% MVC (P < 0.01), but decreased at 80% MVC. The relationship between the peak to peak amplitude of SMG and MU spike indicated significant positive correlations (r = 0.631 to approximately 0.657, P < 0.01). During electrical stimulation at 5 Hz, the SMG power spectral peak frequency (PF) was matched with stimulation frequency in both muscles. At higher stimulation frequencies, e.g., > 15 Hz, only in the MG was SMG-PF synchronized with stimulation frequency; the slow SOL did not show such synchronization. Our data suggest that the SMG frequency components might reflect active motor unit firing rates, and that the SMG amplitude depends upon mechanical properties of contraction, muscle fiber composition, and firing rate during voluntary and electrically induced contractions.
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Affiliation(s)
- Y Yoshitake
- Laboratory of Applied Physiology, The Graduate School of Human and Environmental Studies, Kyoto, University, Japan
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