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Xu Y, Du Z, Cheng A, Lin R, Wang K, Jin Y, Dai C, Xu L. Functional force stimulation alters motor neuron discharge patterns. Front Neurosci 2023; 17:1293017. [PMID: 38116068 PMCID: PMC10728294 DOI: 10.3389/fnins.2023.1293017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Accepted: 11/15/2023] [Indexed: 12/21/2023] Open
Abstract
Introduction Beneficial effects have been observed for mechanical vibration stimulation (MVS), which are mainly attributed to tonic vibration reflex (TVR). TVR is reported to elicit synchronized motor unit activation during locally applied vibration. Similar effects are also observed in a novel vibration system referred to as functional force stimulation (FFS). However, the manifestation of TVR in FFS is doubted due to the use of global electromyography (EMG) features in previous analysis. Our study aims to investigate the effects of FFS on motor unit discharge patterns of the human biceps brachii by analyzing the motor unit spike trains decoded from the high-density surface EMG. Methods Eighteen healthy subjects volunteered in FFS training with different amplitudes and frequencies. One hundred and twenty-eight channel surface EMG was recorded from the biceps brachii and then decoded after motion-artifact removal. The discharge timings were extracted and the coherence between different motor unit spike trains was calculated to quantify synchronized activation. Results and discussion Significant synchronization within the vibration cycle and/or its integer multiples is observed for all FFS trials, which increases with increased FFS amplitude. Our results reveal the basic physiological mechanism involved in FFS, providing a theoretical foundation for analyzing and introducing FFS into clinical rehabilitation programs.
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Affiliation(s)
- Yaodan Xu
- School of Information Science and Technology, ShanghaiTech University, Shanghai, China
- Shanghai Advanced Research Institute, Chinese Academy of Science, Shanghai, China
- University of Chinese Academy of Science, Beijing, China
| | - Zuyu Du
- School of Information Science and Technology, ShanghaiTech University, Shanghai, China
| | - Anyi Cheng
- School of Information Science and Technology, ShanghaiTech University, Shanghai, China
- Shanghai Advanced Research Institute, Chinese Academy of Science, Shanghai, China
- University of Chinese Academy of Science, Beijing, China
| | - Runwei Lin
- School of Information Science and Technology, ShanghaiTech University, Shanghai, China
| | - Kaichen Wang
- School of Information Science and Technology, ShanghaiTech University, Shanghai, China
| | - Yibin Jin
- School of Information Science and Technology, ShanghaiTech University, Shanghai, China
| | - Chenyun Dai
- School of Information Science and Technology, Fudan University, Shanghai, China
| | - Lin Xu
- School of Information Science and Technology, ShanghaiTech University, Shanghai, China
- Shanghai Engineering Research Center of Energy Efficient and Custom AI IC, Shanghai, China
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Buscà B, Aguilera-Castells J, Arboix-Alió J, Miró A, Fort-Vanmeerhaeghe A, Huertas P, Peña J. Superimposed vibration on suspended push-ups. PeerJ 2022; 10:e14435. [PMID: 36518295 PMCID: PMC9744143 DOI: 10.7717/peerj.14435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Accepted: 10/31/2022] [Indexed: 12/03/2022] Open
Abstract
Background Superimposition of vibration has been proposed in sports training using several devices and methods to enhance muscle activation and strength adaptations. Due to the popularity of suspension training, vibration systems have recently been developed to increase the effects of this training method. The present cross-sectional study aims to examine the effects of superimposing vibration on one of the most popular exercises in strength and conditioning programs: push-ups. Methods Twenty-eight physically active men and women executed push-ups in three suspended conditions (non-vibration, vibration at 25 Hz, and vibration at 40 Hz). OMNI-Res scale was registered, and surface electromyographic signals were measured for the activity of the right and left external oblique, anterior deltoid, triceps brachii, sternal, and clavicular heads of the pectoralis major. Results A linear mixed model indicated a significant fixed effect for vibration at 25 Hz and 40 Hz on muscle activity. Suspended push-ups with superimposed vibration (25 Hz and 40 Hz) showed a significant higher activity on left (25 Hz: p = 0.036, d = 0.34; 40 Hz: p = 0.003, d = 0.48) and right external oblique (25 Hz: p = 0.004, d = 0.36; 40 Hz: p = 0.000, d = 0.59), anterior deltoid (25 Hz: p = 0.032, d = 0.44; 40 Hz: p = 0.003, d = 0.64), and global activity (25 Hz: p = 0.000, d = 0.55; 40 Hz: p = 0.000, d = 0.83) compared to non-vibration condition. Moreover, OMNI-Res significant differences were found at 25 Hz (6.04 ± 0.32, p = 0.000 d = 4.03 CI = 3.27, 4.79) and 40 Hz (6.21 ± 0.36 p = 0.00 d = 4.29 CI = 3.49, 5.08) compared to the non-vibration condition (4.75 ± 0.32). Conclusion Superimposing vibration is a feasible strategy to enhance the muscle activity of suspended push-ups.
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Affiliation(s)
- Bernat Buscà
- Faculty of Psychology, Education Sciences, and Sport Blanquerna, Ramon Llull University, Barcelona, Spain
| | - Joan Aguilera-Castells
- Faculty of Psychology, Education Sciences, and Sport Blanquerna, Ramon Llull University, Barcelona, Spain
| | - Jordi Arboix-Alió
- Faculty of Psychology, Education Sciences, and Sport Blanquerna, Ramon Llull University, Barcelona, Spain,School of Health Science Blanquerna, Ramon Llull University, Barcelona, Spain
| | - Adrià Miró
- Faculty of Psychology, Education Sciences, and Sport Blanquerna, Ramon Llull University, Barcelona, Spain
| | - Azahara Fort-Vanmeerhaeghe
- Faculty of Psychology, Education Sciences, and Sport Blanquerna, Ramon Llull University, Barcelona, Spain,School of Health Science Blanquerna, Ramon Llull University, Barcelona, Spain
| | - Pol Huertas
- Faculty of Psychology, Education Sciences, and Sport Blanquerna, Ramon Llull University, Barcelona, Spain
| | - Javier Peña
- Sport and Physyical Activity Studies Centre (CEEAF), University of Vic-Central University of Catalonia, Vic, Spain,Sport performance Analysis Research Group (SPARG), University of Vic-Central University of Catalonia, Vic, Spain
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Xu Y, Wang K, Jin Y, Qiu F, Yao Y, Xu L. Influence of electrode configuration on muscle-fiber-conduction-velocity estimation using surface electromyography. IEEE Trans Biomed Eng 2022; 69:2414-2422. [PMID: 35077351 DOI: 10.1109/tbme.2022.3145038] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Muscle fiber conduction velocity (MFCV) is an important myoelectric parameter and can be estimated by analyzing surface electromyography (EMG). Among many factors, electrode configuration plays a key role on MFCV estimation. Most studies adopt bipolar configuration (BC) for CV estimation. However, a thorough understanding of the underlying mechanism is lacking, confusing the design of the most appropriate EMG measurement setup for CV estimation. The aim of this study is therefore to systematically investigate the influence of electrode configuration on MFCV estimation. METHODS Four possible configurations are considered, including BC, monopolar configuration (MC), common average reference (CAR), and a special monopolar configuration (SMC) using a fix channel on the active muscle as reference. For each configuration, mathematic models computing the time delay between adjacent channels are derived and evaluated by dedicated simulation as well as real EMG measurements. MFCV was calculated using the maximum likelihood algorithm with and without channel normalization. RESULTS The simulation results are in line with the mathematical models. The CVs estimated from the real EMG with and without normalization are 4.30.7 and 7.23.7 m/s, 5.71.3 and 20.44.7 m/s, 9.03.4 and 20.69.8 m/s, and 5.52.5 and 5.52.4 m/s for BC, MC, SMC, and CAR, respectively. CONCLUSION Our results show normalized BC to produce the most accurate CV estimation, in line with the mathematical models and the simulation results. SIGNIFICANCE These findings enable a better understanding of the influence of electrode configuration on MFCV estimation, providing useful information for EMG measurement setup design aiming at MFCV studies.
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Peri E, Xu L, Ciccarelli C, Vandenbussche NL, Xu H, Long X, Overeem S, van Dijk JP, Mischi M. Singular Value Decomposition for Removal of Cardiac Interference from Trunk Electromyogram. SENSORS 2021; 21:s21020573. [PMID: 33467431 PMCID: PMC7829983 DOI: 10.3390/s21020573] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 01/04/2021] [Accepted: 01/12/2021] [Indexed: 01/10/2023]
Abstract
A new algorithm based on singular value decomposition (SVD) to remove cardiac contamination from trunk electromyography (EMG) is proposed. Its performance is compared to currently available algorithms at different signal-to-noise ratios (SNRs). The algorithm is applied on individual channels. An experimental calibration curve to adjust the number of SVD components to the SNR (0–20 dB) is proposed. A synthetic dataset is generated by the combination of electrocardiography (ECG) and EMG to establish a ground truth reference for validation. The performance is compared with state-of-the-art algorithms: gating, high-pass filtering, template subtraction (TS), and independent component analysis (ICA). Its applicability on real data is investigated in an illustrative diaphragm EMG of a patient with sleep apnea. The SVD-based algorithm outperforms existing methods in reconstructing trunk EMG. It is superior to the others in the time (relative mean squared error < 15%) and frequency (shift in mean frequency < 1 Hz) domains. Its feasibility is proven on diaphragm EMG, which shows a better agreement with the respiratory cycle (correlation coefficient = 0.81, p-value < 0.01) compared with TS and ICA. Its application on real data is promising to non-obtrusively estimate respiratory effort for sleep-related breathing disorders. The algorithm is not limited to the need for additional reference ECG, increasing its applicability in clinical practice.
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Affiliation(s)
- Elisabetta Peri
- Department of Electrical Engineering, Eindhoven University of Technology, 5600 MB Eindhoven, The Netherlands; (C.C.); (H.X.); (X.L.); (S.O.); (J.P.v.D.); (M.M.)
- Correspondence:
| | - Lin Xu
- School of Information Science and Technology, ShanghaiTech University, Shanghai 201210, China;
| | - Christian Ciccarelli
- Department of Electrical Engineering, Eindhoven University of Technology, 5600 MB Eindhoven, The Netherlands; (C.C.); (H.X.); (X.L.); (S.O.); (J.P.v.D.); (M.M.)
| | - Nele L. Vandenbussche
- Center for Sleep Medicine, Kempenhaeghe, P.O. Box 61, 5590 AB Heeze, The Netherlands;
| | - Hongji Xu
- Department of Electrical Engineering, Eindhoven University of Technology, 5600 MB Eindhoven, The Netherlands; (C.C.); (H.X.); (X.L.); (S.O.); (J.P.v.D.); (M.M.)
| | - Xi Long
- Department of Electrical Engineering, Eindhoven University of Technology, 5600 MB Eindhoven, The Netherlands; (C.C.); (H.X.); (X.L.); (S.O.); (J.P.v.D.); (M.M.)
| | - Sebastiaan Overeem
- Department of Electrical Engineering, Eindhoven University of Technology, 5600 MB Eindhoven, The Netherlands; (C.C.); (H.X.); (X.L.); (S.O.); (J.P.v.D.); (M.M.)
- Center for Sleep Medicine, Kempenhaeghe, P.O. Box 61, 5590 AB Heeze, The Netherlands;
| | - Johannes P. van Dijk
- Department of Electrical Engineering, Eindhoven University of Technology, 5600 MB Eindhoven, The Netherlands; (C.C.); (H.X.); (X.L.); (S.O.); (J.P.v.D.); (M.M.)
- Center for Sleep Medicine, Kempenhaeghe, P.O. Box 61, 5590 AB Heeze, The Netherlands;
- Department of Orthodontics, University of Ulm, 89081 Ulm, Germany
| | - Massimo Mischi
- Department of Electrical Engineering, Eindhoven University of Technology, 5600 MB Eindhoven, The Netherlands; (C.C.); (H.X.); (X.L.); (S.O.); (J.P.v.D.); (M.M.)
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Xu L, Peri E, Vullings R, Rabotti C, Van Dijk JP, Mischi M. Comparative Review of the Algorithms for Removal of Electrocardiographic Interference from Trunk Electromyography. SENSORS (BASEL, SWITZERLAND) 2020; 20:E4890. [PMID: 32872470 PMCID: PMC7506664 DOI: 10.3390/s20174890] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 08/23/2020] [Accepted: 08/24/2020] [Indexed: 11/29/2022]
Abstract
Surface electromyogram (EMG) is a noninvasive measure of muscle electrical activity and has been widely used in a variety of applications. When recorded from the trunk, surface EMG can be contaminated by the cardiac electrical activity, i.e., the electrocardiogram (ECG). ECG may distort the desired EMG signal, complicating the extraction of reliable information from the trunk EMG. Several methods are available for ECG removal from the trunk EMG, but a comparative assessment of the performance of these methods is lacking, limiting the possibility of selecting a suitable method for specific applications. The aim of the present study is therefore to review and compare the performance of different ECG removal methods from the trunk EMG. To this end, a synthetic dataset was generated by combining in vivo EMG signals recorded on the biceps brachii and healthy or dysrhythmia ECG data from the Physionet database with a predefined signal-to-noise ratio. Gating, high-pass filtering, template subtraction, wavelet transform, adaptive filtering, and blind source separation were implemented for ECG removal. A robust measure of Kurtosis, i.e., KR2 and two EMG features, the average rectified value (ARV), and mean frequency (MF), were then calculated from the processed EMG signals and compared with the EMG before mixing. Our results indicate template subtraction to produce the lowest root mean square error in both ARV and MF, providing useful insight for the selection of a suitable ECG removal method.
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Affiliation(s)
- Lin Xu
- School of Information Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Elisabetta Peri
- Department of Electrical Engineering, Eindhoven University of Technology, 5600 MB Eindhoven, The Netherlands; (E.P.); (R.V.); (J.P.V.D.); (M.M.)
| | - Rik Vullings
- Department of Electrical Engineering, Eindhoven University of Technology, 5600 MB Eindhoven, The Netherlands; (E.P.); (R.V.); (J.P.V.D.); (M.M.)
| | | | - Johannes P. Van Dijk
- Department of Electrical Engineering, Eindhoven University of Technology, 5600 MB Eindhoven, The Netherlands; (E.P.); (R.V.); (J.P.V.D.); (M.M.)
- Clinical Physics Department at Kempenhaeghe, 6532 SZ Nijmegen, The Netherlands
| | - Massimo Mischi
- Department of Electrical Engineering, Eindhoven University of Technology, 5600 MB Eindhoven, The Netherlands; (E.P.); (R.V.); (J.P.V.D.); (M.M.)
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Gündüz A, Ayas S, Kofler M, Aydın Ş, Kızıltan ME. Modulation of the excitatory phase following the cutaneous silent period by vibration. Neurol Sci 2020; 42:633-637. [PMID: 32648049 DOI: 10.1007/s10072-020-04557-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Accepted: 07/02/2020] [Indexed: 10/23/2022]
Abstract
INTRODUCTION The post-inhibition excitatory phase (E3) of the cutaneous silent period (CSP) is attributed to the resynchronization of motoneuron activity following the inhibitory period but there is also evidence that a somatosensory startle reflex may contribute to this phase. We hypothesized that the startle reflex component contained in E3 will decrease during vibration. METHODS Sixteen healthy individuals were included in the study. CSP was recorded from slightly contracted right thenar muscles after painful index finger stimulation, before, during, and immediately after vibration. The values of the percentage change of E3 relative to pre-stimulus baseline (E3%) were compared before, during, and after vibration for each individual. RESULTS There was a reduction in E3% during vibration and the values returned to normal immediately after vibration (153.1 ± 43.5%, 115.2 ± 30.2%, 154.9 ± 68.2%, respectively; p = 0.030). DISCUSSION E3 is reduced during vibration in healthy individuals, presumably due to suppression of a reflex component, which is superimposed upon the known resynchronization of motoneurons.
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Affiliation(s)
- Ayşegül Gündüz
- Department of Neurology, Cerrahpasa School of Medicine, Istanbul University-Cerrahpasa, Istanbul, Turkey
| | - Selahattin Ayas
- Department of Neurology, Cerrahpasa School of Medicine, Istanbul University-Cerrahpasa, Istanbul, Turkey.
| | - Markus Kofler
- Department of Neurology, Hochzirl Hospital, Zirl, Austria
| | - Şenay Aydın
- Department of Neurology, Cerrahpasa School of Medicine, Istanbul University-Cerrahpasa, Istanbul, Turkey
| | - Meral Erdemir Kızıltan
- Department of Neurology, Cerrahpasa School of Medicine, Istanbul University-Cerrahpasa, Istanbul, Turkey
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Xu Y, Xu L, Long X, Mischi M. Relevance of spectral peaks in electromyographic recordings during force-modulated vibration exercise. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2020; 2020:3106-3109. [PMID: 33018662 DOI: 10.1109/embc44109.2020.9176045] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Vibration exercise (VE) has been suggested for effective muscle training and conditioning. Surface electromyogram (EMG) is employed as a powerful tool for the analysis of VE. However, sharp peaks are observed in the EMG spectrum. The interpretation of these peaks is controversial, complicating the extraction of EMG parameters for VE analysis. The present study is therefore aiming at quantifying the relevance of these spectral peaks in EMG recording during VE. To this end, surface EMG was recorded on the biceps brachii during VE at different amplitudes and frequencies. The power percentage contained in the two narrow bands (±0.5 Hz) around the vibration frequency and its first harmonic (PPv) was calculated. The root mean square (RMS) value of the EMG was calculated with and without including the spectral peaks and then compared. The results show an average PPv value of 20.7 ± 7.9 % and a relative RMS difference (∆RMS) of 12.2 ± 3.8 %. In PPv and addition, RMS∆ seem to be influenced by vibration amplitude and frequency. Our results provide useful information for the analysis of VE and contribute to better understanding of the EMG spectral peaks.
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Hussain J, Sundaraj K, Subramaniam ID, Lam CK. Muscle Fatigue in the Three Heads of Triceps Brachii During Intensity and Speed Variations of Triceps Push-Down Exercise. Front Physiol 2020; 11:112. [PMID: 32153422 PMCID: PMC7047337 DOI: 10.3389/fphys.2020.00112] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Accepted: 01/30/2020] [Indexed: 11/16/2022] Open
Abstract
The objective of this study was to investigate the effects of changes in exercise intensity and speed on the three heads of the triceps brachii (TB) during triceps push-down exercise until task failure. Twenty-five subjects performed triceps push-down exercise at three different intensities (30, 45, and 60% 1RM) and speeds (slow, medium, and fast) until failure, and surface electromyography (sEMG) signals were recorded from the lateral, long and medial heads of the TB. The endurance time (ET), number of repetitions (NR) and rate of fatigue (ROF) were analyzed. Subsequently, the root-mean-square (RMS), mean power frequency (MPF) and median frequency (MDF) under no-fatigue (NF) and fatigue (Fa) conditions were statistically compared. The findings reveal that ROF increases with increase in the intensity and speed, and the opposite were obtained for the ET. The ROF in the three heads were comparable for all intensities and speeds. The ROF showed a significant difference (P < 0.05) among the three intensities and speeds for all heads. The three heads showed significantly different (P < 0.05) MPF and MDF values for all the performed exercises under both conditions, whereas the RMS values were significantly different only under Fa conditions. The current observations suggest that exercise intensity and speed affect the ROF while changes in intensity do not affect the MPF and MDF under Fa conditions. The behavior of the spectral parameters indicate that the three heads do not work in unison under any of the conditions. Changes in the speed of triceps push-down exercise affects the lateral and long heads, but changes in the exercise intensity affected the attributes of all heads to a greater extent.
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Affiliation(s)
- Jawad Hussain
- Centre for Telecommunication Research & Innovation, Fakulti Kejuruteraan Elektronik & Kejuruteraan Komputer, Universiti Teknikal Malaysia Melaka, Malacca, Malaysia
| | - Kenneth Sundaraj
- Centre for Telecommunication Research & Innovation, Fakulti Kejuruteraan Elektronik & Kejuruteraan Komputer, Universiti Teknikal Malaysia Melaka, Malacca, Malaysia
| | - Indra Devi Subramaniam
- Centre for Technopreneurship Development, Pusat Bahasa & Pembangunan Insan, Universiti Teknikal Malaysia Melaka, Malacca, Malaysia
| | - Chee Kiang Lam
- School of Mechatronic Engineering, Universiti Malaysia Perlis, Perlis, Malaysia
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Pujari AN, Neilson RD, Cardinale M. Fatiguing effects of indirect vibration stimulation in upper limb muscles: pre, post and during isometric contractions superimposed on upper limb vibration. ROYAL SOCIETY OPEN SCIENCE 2019; 6:190019. [PMID: 31824681 PMCID: PMC6837201 DOI: 10.1098/rsos.190019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Accepted: 09/08/2019] [Indexed: 05/13/2023]
Abstract
Whole-body vibration and upper limb vibration (ULV) continue to gain popularity as exercise intervention for rehabilitation and sports applications. However, the fatiguing effects of indirect vibration stimulation are not yet fully understood. We investigated the effects of ULV stimulation superimposed on fatiguing isometric contractions using a purpose developed upper limb stimulation device. Thirteen healthy volunteers were exposed to both ULV superimposed to fatiguing isometric contractions (V) and isometric contractions alone Control (C). Both Vibration (V) and Control (C) exercises were performed at 80% of the maximum voluntary contractions. The stimulation used was 30 Hz frequency of 0.4 mm amplitude. Surface-electromyographic (EMG) activity of the Biceps Brachii, Triceps Brachii and Flexor Carpi Radialis were measured. EMG amplitude (EMGrms) and mean frequency (MEF) were computed to quantify muscle activity and fatigue levels. All muscles displayed significantly higher reduction in MEFs and a corresponding significant increase in EMGrms with the V than the Control, during fatiguing contractions (p < 0.05). Post vibration, all muscles showed higher levels of MEFs after recovery compared to the control. Our results show that near-maximal isometric fatiguing contractions superimposed on vibration stimulation lead to a higher rate of fatigue development compared to the isometric contraction alone in the upper limb muscles. Results also show higher manifestation of mechanical fatigue post treatment with vibration compared to the control. Vibration superimposed on isometric contraction not only seems to alter the neuromuscular function during fatiguing efforts by inducing higher neuromuscular load but also post vibration treatment.
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Affiliation(s)
- Amit N. Pujari
- School of Engineering, University of Aberdeen, Aberdeen AB24 3DX, UK
- School of Engineering and Technology, University of Hertfordshire, Hatfield AL10 9AB, UK
| | | | - Marco Cardinale
- Department of Computer Science, University College London, London WC1E 6EA, UK
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Aydın Ş, Kofler M, Bakuy Y, Gündüz A, Kızıltan ME. Effects of vibration on cutaneous silent period. Exp Brain Res 2019; 237:911-918. [PMID: 30659303 DOI: 10.1007/s00221-018-05463-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2018] [Accepted: 12/21/2018] [Indexed: 12/14/2022]
Abstract
Suppression of an ongoing muscle contraction following noxious digital stimulation is called cutaneous silent period (CSP) which is under the influence of several physiological factors. In this study, we aimed to evaluate the influence of group Ia afferents on the cutaneous silent period (CSP) by applying 2-min vibration. CSP was obtained from abductor pollicis brevis muscle after stimulating index finger. The recordings were repeated three times-before, during and after vibration-which was applied over the tendon of flexor carpi radialis muscle. Onset latency, duration and magnitude of total CSP, inhibitory phases I1 and I2, and of the long-loop reflex were measured and compared. Suppression indices of CSP, I1 and I2 increased significantly during and after vibration, indicating significantly less exteroceptive EMG suppression outlasting the time of vibration. Vibration also caused mild shortening of I2 end latency (p = 0.048) and I2 duration (p = 0.019). Our findings indicate that vibration exerts a powerful influence on CSPs and causes reduction in the magnitude of exteroceptive EMG suppression during and after vibration. Although vibration is known to activate Ia afferents, we cannot exclude contribution of other afferents, e.g. mechanoreceptors, as well as pre- or postsynaptic inhibitory effects on ensuing interneurons, or enhanced vibration-related excitatory influence.
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Affiliation(s)
- Şenay Aydın
- Department of Neurology, Yedikule Chest Diseases and Chest Surgery Training and Research Hospital, Istanbul, Turkey. .,Department of Neurology, Cerrahpasa Medical Faculty, Istanbul University-Cerrahpasa, Istanbul, Turkey.
| | - Markus Kofler
- Department of Neurology, Hochzirl Hospital, Zirl, Austria
| | - Yeliz Bakuy
- Department of Neurology, Cerrahpasa Medical Faculty, Istanbul University-Cerrahpasa, Istanbul, Turkey
| | - Ayşegül Gündüz
- Department of Neurology, Cerrahpasa Medical Faculty, Istanbul University-Cerrahpasa, Istanbul, Turkey
| | - Meral E Kızıltan
- Department of Neurology, Cerrahpasa Medical Faculty, Istanbul University-Cerrahpasa, Istanbul, Turkey
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