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Gallardo P, Giakas G, Sakkas GK, Tsaklis PV. Are Surface Electromyography Parameters Indicative of Post-Activation Potentiation/Post-Activation Performance Enhancement, in Terms of Twitch Potentiation and Voluntary Performance? A Systematic Review. J Funct Morphol Kinesiol 2024; 9:106. [PMID: 38921642 PMCID: PMC11205249 DOI: 10.3390/jfmk9020106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2024] [Revised: 06/06/2024] [Accepted: 06/10/2024] [Indexed: 06/27/2024] Open
Abstract
The aim was to identify if surface electromyography (sEMG) parameters are indicative of post-activation potentiation (PAP)/post-activation performance enhancement (PAPE), in terms of twitch potentiation and voluntary performance. Three databases were used in April 2024, with the following inclusion criteria: (a) original research, assessed in healthy human adults, and (b) sEMG parameters were measured. The exclusion criteria were (a) studies with no PAP/PAPE protocol and (b) non-randomized control trials. The following data were extracted: study characteristics/demographics, PAP/PAPE protocols, sEMG parameters, twitch/performance outcomes, and study findings. A modified physiotherapy evidence database (PEDro) scale was used for quality assessment. Fifteen randomized controlled trials (RCTs), with a total of 199 subjects, were included. The M-wave amplitude (combined with a twitch torque outcome) was shown to generally be indicative of PAP. The sEMG amplitudes (in some muscles) were found to be indicative of PAPE during ballistic movements, while a small decrease in the MdF (in certain muscles) was shown to reflect PAPE. Changes in the Hmax/Mmax ratio were found to contribute (temporally) to PAP, while the H-reflex amplitude was shown to be neither indicative of PAP nor PAPE. This review provides preliminary findings suggesting that certain sEMG parameters could be indicative of PAP/PAPE. However, due to limited studies, future research is warranted.
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Affiliation(s)
- Philip Gallardo
- Department of Physical Education and Sport Science, ErgoMech-Lab, University of Thessaly, 421 00 Trikala, Greece; (P.G.); (G.G.); (G.K.S.)
| | - Giannis Giakas
- Department of Physical Education and Sport Science, ErgoMech-Lab, University of Thessaly, 421 00 Trikala, Greece; (P.G.); (G.G.); (G.K.S.)
| | - Giorgos K. Sakkas
- Department of Physical Education and Sport Science, ErgoMech-Lab, University of Thessaly, 421 00 Trikala, Greece; (P.G.); (G.G.); (G.K.S.)
| | - Panagiotis V. Tsaklis
- Department of Physical Education and Sport Science, ErgoMech-Lab, University of Thessaly, 421 00 Trikala, Greece; (P.G.); (G.G.); (G.K.S.)
- Department Molecular Medicine and Surgery, Growth and Metabolism, Karolinska Institute, 171 77 Solna, Sweden
- Center of Orthopaedics and Regenerative Medicine (C.O.RE.)/(C.I.R.I.), Aristotle University Thessaloniki, 541 24 Thessaloniki, Greece
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Stoffels AAF, Allard NAE, Spruit MA, Klijn P, Hopman MTE, Meys R, Franssen FME, Timmers S, van den Borst B, van Hees HWH. Relationship between Volitional and Non-Volitional Quadriceps Muscle Endurance in Patients with Chronic Obstructive Pulmonary Disease. Diagnostics (Basel) 2024; 14:190. [PMID: 38248067 PMCID: PMC10814454 DOI: 10.3390/diagnostics14020190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 12/24/2023] [Accepted: 01/03/2024] [Indexed: 01/23/2024] Open
Abstract
Volitional assessment of quadriceps muscle endurance is clinically relevant in patients with chronic obstructive pulmonary disease (COPD). However, studies that determine the construct validity of volitional tests by comparing them to non-volitional measures are lacking. Therefore, the aim of the current study is to evaluate the correlation between volitional and non-volitional quadriceps muscle endurance in patients with COPD. Quadriceps muscle endurance was evaluated in twenty-six patients with COPD. A volitional isometric and a volitional isokinetic protocol were performed on a computerised dynamometer to determine the isometric time and isokinetic work fatigue index, respectively. Non-volitional assessment of quadriceps muscle endurance was evaluated using repetitive electrical stimulations to establish the isometric muscle force decline. Sixteen patients (61 ± 8 years, 63% male, FEV1 47 (32-53)%) performed all three quadriceps endurance tests conforming to pre-defined test criteria. Both volitional isometric time and isokinetic work fatigue index did not significantly correlate with non-volitional muscle force decline (both p > 0.05). There was a strong correlation between volitional isometric time and isokinetic work fatigue index (rho = -0.716, p = 0.002). To conclude, this study suggests that volitional measures evaluate partly different aspects of quadriceps muscle endurance compared to non-volitional measures. Accordingly, these outcome measures cannot be used interchangeably.
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Affiliation(s)
- Anouk A. F. Stoffels
- Department of Pulmonary Diseases, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands (B.v.d.B.)
| | - Neeltje A. E. Allard
- Department of Physiology, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands (M.T.E.H.)
| | - Martijn A. Spruit
- Department of Research and Development, Ciro, 6085 NM Horn, The Netherlands; (M.A.S.); (R.M.); (F.M.E.F.)
- NUTRIM School of Nutrition and Translational Research in Metabolism, Faculty of Health and Life Sciences, Maastricht University, 6229 HX Maastricht, The Netherlands
- Department of Respiratory Medicine, Maastricht University Medical Centre (MUMC+), 6229 HX Maastricht, The Netherlands
| | - Peter Klijn
- Department of Pulmonology, Merem Pulmonary Rehabilitation Centre, 1213 VX Hilversum, The Netherlands;
- Department of Pulmonary Medicine, Amsterdam University Medical Centre, 1105 AZ Amsterdam, The Netherlands
| | - Maria T. E. Hopman
- Department of Physiology, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands (M.T.E.H.)
| | - Roy Meys
- Department of Research and Development, Ciro, 6085 NM Horn, The Netherlands; (M.A.S.); (R.M.); (F.M.E.F.)
- NUTRIM School of Nutrition and Translational Research in Metabolism, Faculty of Health and Life Sciences, Maastricht University, 6229 HX Maastricht, The Netherlands
- Department of Respiratory Medicine, Maastricht University Medical Centre (MUMC+), 6229 HX Maastricht, The Netherlands
| | - Frits M. E. Franssen
- Department of Research and Development, Ciro, 6085 NM Horn, The Netherlands; (M.A.S.); (R.M.); (F.M.E.F.)
- NUTRIM School of Nutrition and Translational Research in Metabolism, Faculty of Health and Life Sciences, Maastricht University, 6229 HX Maastricht, The Netherlands
- Department of Respiratory Medicine, Maastricht University Medical Centre (MUMC+), 6229 HX Maastricht, The Netherlands
| | - Silvie Timmers
- Human and Animal Physiology, Wageningen University, 6708 WD Wageningen, The Netherlands;
| | - Bram van den Borst
- Department of Pulmonary Diseases, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands (B.v.d.B.)
| | - Hieronymus W. H. van Hees
- Department of Pulmonary Diseases, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands (B.v.d.B.)
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Chen W, Jiang T, Huang H, Zeng J. Post-stroke fatigue: a review of development, prevalence, predisposing factors, measurements, and treatments. Front Neurol 2023; 14:1298915. [PMID: 38187145 PMCID: PMC10768193 DOI: 10.3389/fneur.2023.1298915] [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: 09/22/2023] [Accepted: 12/01/2023] [Indexed: 01/09/2024] Open
Abstract
Background Post-stroke fatigue (PSF) is a ubiquitous and overwhelming symptom for most stroke survivors. However, there are no effective management strategies for PSF, which is partly due to our limited understanding. Objective In this paper, we review the development, prevalence, predisposing factors, measurements, and treatments of PSF. Results PSF is an independent symptom after stroke, with a prevalence ranging from 42 to 53%, which depends on the selection of measurement tools and stroke characteristics. It is affected by biological, physical, and psychological factors, among which inflammation may play a key role. Conclusion Numerous but non-specific evaluation measurement tools limit the management of PSF. In clinical practice, it may be beneficial to identify PSF by combining scales and objective indexes, such as walking tests and electromyographic examinations. There are no evidence-based interventions to improve PSF. However, increasing evidence suggests that transcranial direct-current stimulation and mindfulness-based interventions may become promising treatments. Further studies are urgently needed to better understand the etiology of PSF, thereby providing the basis for developing new measurement tools and targeted treatments.
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Affiliation(s)
| | - Tao Jiang
- Department of Neurology, The Third Affiliated Hospital of Southern Medical University, Guangzhou, China
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Age-sensitive high density surface electromyogram indices for detecting muscle fatigue using core shape modelling. Biomed Signal Process Control 2023. [DOI: 10.1016/j.bspc.2022.104446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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García-Aguilar F, Caballero C, Sabido R, Moreno FJ. The use of non-linear tools to analyze the variability of force production as an index of fatigue: A systematic review. Front Physiol 2022; 13:1074652. [PMID: 36589460 PMCID: PMC9795073 DOI: 10.3389/fphys.2022.1074652] [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: 10/19/2022] [Accepted: 11/16/2022] [Indexed: 12/15/2022] Open
Abstract
Background: Fatigue is a process that results in a decreased ability to produce force, and which could eventually affect performance and increase the risk of injury. Force variability analysis has been proposed to describe the level of fatigue with the purpose of detecting the development of fatigue. Variability is credited to play a functional and adaptive role through which the components of a system self-organize to solve a motor problem. Non-linear tools have been applied to analyze the variability of physiological signals, revealing that the structure of motor fluctuations provides relevant information about the functional role of variability. It has been suggested that the presence of lower complexity in the variability structure could reveal a less functional and adaptative state (e.g., ageing or illness). In the last years, an increased number of studies have applied these techniques to force variability analysis in relation to fatigue. Objective: To provide an overview of the current knowledge on the use of non-linear tools on force variability as a fatigue index. Methods: Following PRISMA guidelines, a systematic search of SPORTDiscus, Scopus, Web of Science and PubMed was carried out. Studies included were: a) original studies that analyzed the effect of fatigue on humans during an action focused on force production; b) published studies with their title and abstract in English; c) studies that applied non-linear tools on a signal directly related to force production. Results: Twenty-five studies were included in this review. The relationship between fatigue and the complexity of force variability, the type of action and relative intensity, the nature of the signal and the non-linear tools used, and the methods of data acquisition and processing were identified. Conclusion: The articles reviewed suggest that fatigue leads to a decrease in complexity mostly in isometric contractions, but this is not as clear in dynamic contractions. This fatigue-induced loss of complexity seems to be a result of changes in the nervous system at the central level, albeit triggered by peripheral mechanisms. It should be noted that non-linear tools are affected by the relative intensity of contraction, non-stationarity, and the acquisition and treatment of the signal.
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Negro M, Cerullo G, Perna S, Beretta-Piccoli M, Rondanelli M, Liguori G, Cena H, Phillips SM, Cescon C, D’Antona G. Effects of a Single Dose of a Creatine-Based Multi-Ingredient Pre-workout Supplement Compared to Creatine Alone on Performance Fatigability After Resistance Exercise: A Double-Blind Crossover Design Study. Front Nutr 2022; 9:887523. [PMID: 35799580 PMCID: PMC9255897 DOI: 10.3389/fnut.2022.887523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Accepted: 04/28/2022] [Indexed: 11/25/2022] Open
Abstract
Background This study aims to investigate the acute effects of a single oral administration of a creatine-based multi-ingredient pre-workout supplement (MIPS) on performance fatigability and maximal force production after a resistance exercise protocol (REP). Methods Eighteen adult males (age: 23 ± 1 years; body mass: 76.4 ± 1.5 kg; height: 1.77 ± 0.01 m) were enrolled in a randomized, double-blind, crossover design study. Subjects received a single dose of a MIPS (3 g of creatine, 2 g of arginine, 1 g of glutamine, 1 g of taurine, and 800 mg of β-alanine) or creatine citrate (CC) (3 g of creatine) or a placebo (PLA) in three successive trials 1 week apart. In a randomized order, participants consumed either MIPS, CC, or PLA and performed a REP 2 h later. Before ingestion and immediately after REP, subjects performed isometric contractions of the dominant biceps brachii: two maximal voluntary contractions (MVCs), followed by a 20% MVC for 90 s and a 60% MVC until exhaustion. Surface electromyographic indices of performance fatigability, conduction velocity (CV), and fractal dimension (FD) were obtained from the surface electromyographic signal (sEMG). Time to perform the task (TtT), basal blood lactate (BL), and BL after REP were also measured. Results Following REP, statistically significant (P < 0.05) pre–post mean for ΔTtT between MIPS (−7.06 s) and PLA (+0.222 s), ΔCV slopes (20% MVC) between MIPS (0.0082%) and PLA (−0.0519%) and for ΔCV slopes (60% MVC) between MIPS (0.199%) and PLA (−0.154%) were found. A pairwise comparison analysis showed no statistically significant differences in other variables between groups and condition vs. condition. Conclusion After REP, a creatine-enriched MIPS resulted in greater improvement of sEMG descriptors of performance fatigability and TtT compared with PLA. Conversely, no statistically significant differences in outcomes measured were observed between CC and PLA or MIPS and CC.
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Affiliation(s)
- Massimo Negro
- Centro di Ricerca Interdipartimentale nelle Attività Motorie e Sportive (CRIAMS) – Sport Medicine Centre, University of Pavia, Voghera, Italy
| | - Giuseppe Cerullo
- Department of Movement Sciences and Wellbeing, University of Naples Parthenope, Naples, Italy
| | - Simone Perna
- Department of Biology, College of Science, University of Bahrain, Sakhir, Bahrain
| | - Matteo Beretta-Piccoli
- Rehabilitation Research Laboratory 2rLab, Department of Business Economics, Health and Social Care, University of Applied Sciences and Arts of Southern Switzerland, Manno, Switzerland
| | - Mariangela Rondanelli
- Department of Public Health, Experimental and Forensic Medicine, University of Pavia, Pavia, Italy
- Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Mondino Foundation, Pavia, Italy
| | - Giorgio Liguori
- Department of Movement Sciences and Wellbeing, University of Naples Parthenope, Naples, Italy
| | - Hellas Cena
- Department of Public Health, Experimental and Forensic Medicine, University of Pavia, Pavia, Italy
- Clinical Nutrition and Dietetics Service, Unit of Internal Medicine and Endocrinology, Istituti Clinici Scientifici (ICS) Maugeri Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), University of Pavia, Pavia, Italy
| | - Stuart M. Phillips
- Exercise Metabolism Research Group, Department of Kinesiology, McMaster University, Hamilton, ON, Canada
| | - Corrado Cescon
- Rehabilitation Research Laboratory 2rLab, Department of Business Economics, Health and Social Care, University of Applied Sciences and Arts of Southern Switzerland, Manno, Switzerland
| | - Giuseppe D’Antona
- Centro di Ricerca Interdipartimentale nelle Attività Motorie e Sportive (CRIAMS) – Sport Medicine Centre, University of Pavia, Voghera, Italy
- Department of Public Health, Experimental and Forensic Medicine, University of Pavia, Pavia, Italy
- *Correspondence: Giuseppe D’Antona,
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Xu Y, Poon WS, Zheng Y, Zhang S, Hu X. Evaluation of Central Fatigue in Post-stroke Rehabilitation: A Pilot Study. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2021; 2021:6687-6690. [PMID: 34892642 DOI: 10.1109/embc46164.2021.9630323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Central fatigue induced by excessive rehabilitation training would limit motor activity or even damage the post-stroke motor function recovery. However, the central fatigue progress during training is unclear and ignored in post-stroke rehabilitation. In this study, we tried to investigate the changes in central fatigue with fractal dimension (FD) of electromyography (EMG) at different peripheral fatigue levels based on the intracerebral haemorrhage (ICH) model. Ten Sprague-Dawley rats with ICH and EMG electrodes implantation were randomly distributed into two groups: the forced training (FOR) group with exhausted peripheral fatigue level (n=5) and fatigue-controlled (FAT) group (n=5) with peripheral fatigue constrained in moderate level. A higher central fatigue level was found in the FOR group (P<0.0001), and the central fatigue could be alleviated by peripheral fatigue-based modulation in the FAT group. The FAT group with less central fatigue achieved significantly better motor function recovery (P<0.0001), and it might be related to the recovery in the ability of motor unit recruitments.
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Pethick J, Winter SL, Burnley M. Physiological complexity: influence of ageing, disease and neuromuscular fatigue on muscle force and torque fluctuations. Exp Physiol 2021; 106:2046-2059. [PMID: 34472160 DOI: 10.1113/ep089711] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Accepted: 08/26/2021] [Indexed: 11/08/2022]
Abstract
NEW FINDINGS What is the topic of this review? Physiological complexity in muscle force and torque fluctuations, specifically the quantification of complexity, how neuromuscular complexityis altered by perturbations and the potential mechanism underlying changes in neuromuscular complexity. What advances does it highlight? The necessity to calculate both magnitude- and complexity-based measures for the thorough evaluation of force/torque fluctuations. Also the need for further research on neuromuscular complexity, particularly how it relates to the performance of functional activities (e.g. manual dexterity, balance, locomotion). ABSTRACT Physiological time series produce inherently complex fluctuations. In the last 30 years, methods have been developed to characterise these fluctuations, and have revealed that they contain information about the function of the system producing them. Two broad classes of metrics are used: (1) those which quantify the regularity of the signal (e.g. entropy metrics); and (2) those which quantify the fractal properties of the signal (e.g. detrended fluctuation analysis). Using these techniques, it has been demonstrated that ageing results in a loss of complexity in the time series of a multitude of signals, including heart rate, respiration, gait and, crucially, muscle force or torque output. This suggests that as the body ages, physiological systems become less adaptable (i.e. the systems' ability to respond rapidly to a changing external environment is diminished). More recently, it has been shown that neuromuscular fatigue causes a substantial loss of muscle torque complexity, a process that can be observed in a few minutes, rather than the decades it requires for the same system to degrade with ageing. The loss of torque complexity with neuromuscular fatigue appears to occur exclusively above the critical torque (at least for tasks lasting up to 30 min). The loss of torque complexity can be exacerbated with previous exercise of the same limb, and reduced by the administration of caffeine, suggesting both peripheral and central mechanisms contribute to this loss. The mechanisms underpinning the loss of complexity are not known but may be related to altered motor unit behaviour as the muscle fatigues.
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Affiliation(s)
- Jamie Pethick
- School of Sport, Rehabilitation and Exercise Sciences, University of Essex, Colchester, UK
| | - Samantha L Winter
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
| | - Mark Burnley
- Endurance Research Group, School of Sport and Exercise Sciences, University of Kent, Chatham Maritime, UK
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Fatigue-induced changes in knee-extensor torque complexity and muscle metabolic rate are dependent on joint angle. Eur J Appl Physiol 2021; 121:3117-3131. [PMID: 34355267 PMCID: PMC8505307 DOI: 10.1007/s00421-021-04779-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Accepted: 07/25/2021] [Indexed: 01/20/2023]
Abstract
Purpose Joint angle is a significant determinant of neuromuscular and metabolic function. We tested the hypothesis that previously reported correlations between knee-extensor torque complexity and metabolic rate (\documentclass[12pt]{minimal}
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\begin{document}$${\text{m}\dot{\text{V}}\text{O}}_{{2}}$$\end{document}mV˙O2) would be conserved at reduced joint angles (i.e. shorter muscle lengths). Methods Eleven participants performed intermittent isometric knee-extensor contractions at 50% maximum voluntary torque for 30 min or until task failure (whichever occurred sooner) at joint angles of 30º, 60º and 90º of flexion (0º = extension). Torque and surface EMG were sampled continuously. Complexity and fractal scaling of torque were quantified using approximate entropy (ApEn) and detrended fluctuation analysis (DFA) α. \documentclass[12pt]{minimal}
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\begin{document}$${\text{m}\dot{\text{V}}\text{O}}_{{2}}$$\end{document}mV˙O2 was determined using near-infrared spectroscopy. Results Time to task failure/end increased as joint angle decreased (P < 0.001). Over time, complexity decreased at 90º and 60º (decreased ApEn, increased DFA α, both P < 0.001), but not 30º. \documentclass[12pt]{minimal}
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\begin{document}$${\text{m}\dot{\text{V}}\text{O}}_{{2}}$$\end{document}mV˙O2 increased at all joint angles (P < 0.001), though the magnitude of this increase was lower at 30º compared to 60º and 90º (both P < 0.01). There were significant correlations between torque complexity and \documentclass[12pt]{minimal}
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\begin{document}$${\text{m}\dot{\text{V}}\text{O}}_{{2}}$$\end{document}mV˙O2 at 90º (ApEn, r = − 0.60, P = 0.049) and 60º (ApEn, r = − 0.64, P = 0.035; DFA α, ρ = 0.68, P = 0.015). Conclusion The lack of correlation between \documentclass[12pt]{minimal}
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\begin{document}$${\text{m}\dot{\text{V}}\text{O}}_{{2}}$$\end{document}mV˙O2 and complexity at 30º was likely due to low relative task demands, given the similar kinetics of \documentclass[12pt]{minimal}
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\begin{document}$${\text{m}\dot{\text{V}}\text{O}}_{{2}}$$\end{document}mV˙O2 and torque complexity. An inverse correlation between \documentclass[12pt]{minimal}
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\begin{document}$${\text{m}\dot{\text{V}}\text{O}}_{{2}}$$\end{document}mV˙O2 and knee-extensor torque complexity occurs during high-intensity contractions at intermediate, but not short, muscle lengths.
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Namazi H. Complexity-based analysis of the correlation between stride interval variability and muscle reaction at different walking speeds. Biomed Signal Process Control 2021. [DOI: 10.1016/j.bspc.2021.102956] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Liu X, Zhou M, Geng Y, Meng L, Wan H, Ren H, Zhang X, Dai C, Chen W, Ye X. Changes in synchronization of the motor unit in muscle fatigue condition during the dynamic and isometric contraction in the Biceps Brachii muscle. Neurosci Lett 2021; 761:136101. [PMID: 34237415 DOI: 10.1016/j.neulet.2021.136101] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 07/01/2021] [Accepted: 07/01/2021] [Indexed: 11/28/2022]
Abstract
The fatigue-induced neuromuscular mechanism remains to be fully elucidated. So far, the macroscopic mechanism using global surface electromyogram (sEMG) has been widely investigated. However, the microscopic mechanism using high-level neural information based on motor unit (MU) spike train from the spinal cord lacks attention, especially for the conditions under dynamic contraction task. The synchronization of the MU spike train is generally assumed to be an excellent indicator to represent the activities of spinal nerves. Accordingly, this study employed synchronization of MU spike train decomposed from high-density sEMG (HD-sEMG) to investigate the fatigue condition in muscular contractions within the Biceps Brachii muscle under both isometric and dynamic contraction tasks, giving a complete picture of the microscopic fatigue mechanism. We compared the synchronization of MU in Delta (1-4 Hz), alpha (8-12 Hz), Beta (15-30 Hz), and Gamma (30-60 Hz) frequency bands during the fatigue condition induced by different contractions. Our results showed that MU synchronization increased significantly (p<0.05) in all frequency bands across the two contraction tasks. The results indicate that the microscopic fatigue mechanism of Biceps Brachii muscle does not vary due to different contraction tasks.
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Affiliation(s)
- Xiangyu Liu
- School of Art Design and Media, East China University of Science and Technology, Shanghai, China.
| | - Meiyu Zhou
- School of Art Design and Media, East China University of Science and Technology, Shanghai, China.
| | - Yanjuan Geng
- Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, China.
| | - Long Meng
- School of Information and Technology, Fudan University, Shanghai, China.
| | - Huiying Wan
- School of Information and Technology, Fudan University, Shanghai, China.
| | - Haoran Ren
- School of Information and Technology, Fudan University, Shanghai, China.
| | - Xinyue Zhang
- School of Education, Hangzhou Normal University, Hangzhou Zhejiang, China.
| | - Chenyun Dai
- School of Information and Technology, Fudan University, Shanghai, China.
| | - Wei Chen
- School of Information and Technology, Fudan University, Shanghai, China.
| | - Xinming Ye
- School of Sports Science and Engineering, East China University of Science and Technology, Shanghai, China.
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Beretta-Piccoli M, Cescon C, Barbero M, D’Antona G. Identification of muscle innervation zones using linear electrode arrays: a fundamental step to measure fibers conduction velocity. ARAB JOURNAL OF BASIC AND APPLIED SCIENCES 2021. [DOI: 10.1080/25765299.2021.1894731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Affiliation(s)
- Matteo Beretta-Piccoli
- Rehabilitation Research Laboratory, Department of Business Economics, Health and Social Care, University of Applied Sciences and Arts of Southern Switzerland, SUPSI, Manno, Switzerland
- Criams-Sport Medicine Centre Voghera, University of Pavia, Pavia, Italy
| | - Corrado Cescon
- Rehabilitation Research Laboratory, Department of Business Economics, Health and Social Care, University of Applied Sciences and Arts of Southern Switzerland, SUPSI, Manno, Switzerland
| | - Marco Barbero
- Rehabilitation Research Laboratory, Department of Business Economics, Health and Social Care, University of Applied Sciences and Arts of Southern Switzerland, SUPSI, Manno, Switzerland
| | - Giuseppe D’Antona
- Criams-Sport Medicine Centre Voghera, University of Pavia, Pavia, Italy
- Department of Public Health, Experimental and Forensic medicine, University of Pavia, Pavia, Italy
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13
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Increased resistance towards fatigability in patients with facioscapulohumeral muscular dystrophy. Eur J Appl Physiol 2021; 121:1617-1629. [PMID: 33646424 PMCID: PMC8144151 DOI: 10.1007/s00421-021-04650-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Accepted: 02/19/2021] [Indexed: 11/01/2022]
Abstract
PURPOSE In facioscapulohumeral muscular dystrophy (FSHD) fatigue is a major complaint. We aimed to investigate whether during isometric sustained elbow flexions, performance fatigability indexes differ in patients with FSHD with respect to healthy controls. METHODS Seventeen patients with FSHD and seventeen healthy controls performed two isometric flexions of the dominant biceps brachii at 20% of their maximal voluntary contraction (MVC) for 2 min and then at 60% MVC until exhaustion. Muscle weakness was characterized as a percentage of predicted values. Maximal voluntary strength, endurance time and performance fatigability indices (mean frequency of the power spectrum (MNF), muscle fiber conduction velocity (CV) and fractal dimension (FD)), extracted from the surface electromyogram signal (sEMG) were compared between the two groups. RESULTS In patients with FSHD, maximal voluntary strength was 68.7% of predicted value (p < 0.01). Compared to healthy controls, FSHD patients showed reduced MVC (p < 0.001; r = 0.62) and lower levels of performance fatigability, characterized by reduced rate of changes in MNF (p < 0.01; r = 0.56), CV (p < 0.05; 0.37) and FD (p < 0.001; r = 0.51) and increased endurance time (p < 0.001; r = 0.63), during the isometric contraction at 60% MVC. CONCLUSION A decreased reduction in the slopes of all the considered sEMG parameters during sustained isometric elbow flexions suggests that patients with FSHD experience lower levels of performance fatigability compared to healthy controls.
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Beretta-Piccoli M, Cescon C, D’Antona G. Evaluation of performance fatigability through surface EMG in health and muscle disease: state of the art. ARAB JOURNAL OF BASIC AND APPLIED SCIENCES 2020. [DOI: 10.1080/25765299.2020.1862985] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Affiliation(s)
- Matteo Beretta-Piccoli
- Criams-Sport Medicine Centre Voghera, University of Pavia, Pavia, Italy
- Rehabilitation Research Laboratory 2rLab, Department of Business Economics, Health and Social Care, University of Applied, Sciences and Arts of Southern Switzerland, Manno, Switzerland
| | - Corrado Cescon
- Rehabilitation Research Laboratory 2rLab, Department of Business Economics, Health and Social Care, University of Applied, Sciences and Arts of Southern Switzerland, Manno, Switzerland
| | - Giuseppe D’Antona
- Criams-Sport Medicine Centre Voghera, University of Pavia, Pavia, Italy
- Department of Public Health, Experimental and Forensic Medicine, University of Pavia, Pavia, Italy
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15
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Rampichini S, Vieira TM, Castiglioni P, Merati G. Complexity Analysis of Surface Electromyography for Assessing the Myoelectric Manifestation of Muscle Fatigue: A Review. ENTROPY (BASEL, SWITZERLAND) 2020; 22:E529. [PMID: 33286301 PMCID: PMC7517022 DOI: 10.3390/e22050529] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Revised: 04/30/2020] [Accepted: 05/02/2020] [Indexed: 01/13/2023]
Abstract
The surface electromyography (sEMG) records the electrical activity of muscle fibers during contraction: one of its uses is to assess changes taking place within muscles in the course of a fatiguing contraction to provide insights into our understanding of muscle fatigue in training protocols and rehabilitation medicine. Until recently, these myoelectric manifestations of muscle fatigue (MMF) have been assessed essentially by linear sEMG analyses. However, sEMG shows a complex behavior, due to many concurrent factors. Therefore, in the last years, complexity-based methods have been tentatively applied to the sEMG signal to better individuate the MMF onset during sustained contractions. In this review, after describing concisely the traditional linear methods employed to assess MMF we present the complexity methods used for sEMG analysis based on an extensive literature search. We show that some of these indices, like those derived from recurrence plots, from entropy or fractal analysis, can detect MMF efficiently. However, we also show that more work remains to be done to compare the complexity indices in terms of reliability and sensibility; to optimize the choice of embedding dimension, time delay and threshold distance in reconstructing the phase space; and to elucidate the relationship between complexity estimators and the physiologic phenomena underlying the onset of MMF in exercising muscles.
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Affiliation(s)
- Susanna Rampichini
- Department of Biomedical Sciences for Health, Università degli Studi di Milano, 20133 Milan, Italy; (S.R.); (G.M.)
| | - Taian Martins Vieira
- Laboratorio di Ingegneria del Sistema Neuromuscolare (LISiN), Dipartimento di Elettronica e Telecomunicazioni, Politecnico di Torino, 10129 Turin, Italy
- PoliToBIOMed Lab, Politecnico di Torino, 10129 Turin, Italy
| | | | - Giampiero Merati
- Department of Biomedical Sciences for Health, Università degli Studi di Milano, 20133 Milan, Italy; (S.R.); (G.M.)
- IRCCS Fondazione Don Carlo Gnocchi, 20148 Milan, Italy;
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16
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Beretta-Piccoli M, Cescon C, Barbero M, Villiger M, Clijsen R, Kool J, Kesselring J, Bansi J. Upper and lower limb performance fatigability in people with multiple sclerosis investigated through surface electromyography: a pilot study. Physiol Meas 2020; 41:025002. [PMID: 31972554 DOI: 10.1088/1361-6579/ab6f54] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
OBJECTIVE Fatigue experienced by people with multiple sclerosis (pwMS) is multidimensional, consisting of different components, such as perceived, physical and cognitive fatigue and performance fatigability. At present, there is no gold standard to assess performance fatigability in pwMS; therefore, we aimed to determine whether, during a fatiguing task, average rectified value (ARV), mean frequency of the power spectrum (MNF), muscle fiber conduction velocity (CV) and fractal dimension (FD) of surface electromyography (sEMG) may be used as indirect indices of performance fatigability. Moreover, we analyzed whether a three-week rehabilitation program impacts on performance fatigability in pwMS, and whether a relationship between sEMG parameters and trait levels of perceived fatigability, before and after rehabilitation, does exist. APPROACH Twenty-one pwMS performed a 20% maximal voluntary contraction (MVC) of 1 min, and afterwards a 60% MVC held until exhaustion. sEMG signals were detected from the biceps brachii, vastus medialis and vastus lateralis. Performance fatigability was determined at entry to (t 0) and discharge from (t 1) rehabilitation. Perceived fatigability was measured at t 0 and t 2, one month after rehabilitation. MAIN RESULTS ARV, MNF, CV and FD rates of change showed significant changes at t 0 and t 1 (p < 0.05) during the high-level contraction in the BB, but rather limited in the vastii muscles. Moreover, rehabilitation did not induce any reductions in either perceived or performance fatigability. No significant correlations between ARV, MNF, CV and FD rates of change during the 60% MVC and perceived fatigability, at t 0 and t 2, were found. SIGNIFICANCE Our findings suggest that the sEMG parameters are useful for indirectly assessing performance fatigability in pwMS during sub-maximal fatiguing contractions, particularly in the biceps brachii.
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Affiliation(s)
- Matteo Beretta-Piccoli
- Rehabilitation Research Laboratory 2rLab, Department of Business Economics, Health and Social Care, University of Applied Sciences and Arts of Southern Switzerland, Manno/Landquart, Switzerland. Author to whom any correspondence should be addressed
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17
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Mugnosso M, Zenzeri J, Hughes CML, Marini F. Coupling Robot-Aided Assessment and Surface Electromyography (sEMG) to Evaluate the Effect of Muscle Fatigue on Wrist Position Sense in the Flexion-Extension Plane. Front Hum Neurosci 2019; 13:396. [PMID: 31736733 PMCID: PMC6838006 DOI: 10.3389/fnhum.2019.00396] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Accepted: 10/22/2019] [Indexed: 11/13/2022] Open
Abstract
Proprioception is a crucial sensory modality involved in the control and regulation of coordinated movements and in motor learning. However, the extent to which proprioceptive acuity is influenced by local muscle fatigue is obscured by methodological differences in proprioceptive and fatiguing protocols. In this study, we used high resolution kinematic measurements provided by a robotic device, as well as both frequency and time domain analysis of signals captured via surface electromyography (sEMG) to examine the effects of local muscle fatigue on wrist proprioceptive acuity in 16 physically and neurologically healthy young adults. To this end, participants performed a flexion/extension ipsilateral joint position matching test (JPM), after which a high-resistive robotic task was used to induce muscle fatigue of the flexor carpi radialis (FCR) muscle. The JPM test was then repeated in order to analyze potential changes in proprioceptive acuity. Results indicated that the fatigue protocol had a significant effect on movements performed in flexion direction, with participants exhibiting a tendency to undershoot the target before the fatigue protocol (−1.218°), but overshooting after the fatigue protocol (0.587°). In contrast, in the extension direction error bias values were similar before and after the fatigue protocol as expected (pre = −1.852°, post = −1.237°) and reflected a tendency to undershoot the target. Moreover, statistical analysis indicated that movement variability was not influenced by the fatigue protocol or movement direction. In sum, results of the present study demonstrate that an individual’s estimation of wrist joint displacement (i.e., error bias), but not precision (i.e., variability), is affected by muscular fatigue in a sample of neurologically and physically healthy adults.
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Affiliation(s)
- Maddalena Mugnosso
- Motor Learning, Assistive and Rehabilitation Robotics Laboratory, Robotics, Brain and Cognitive Sciences Department, Istituto Italiano di Tecnologia, Genoa, Italy.,Department of Informatics, Bioengineering, Robotics and System Engineering, University of Genoa, Genoa, Italy
| | - Jacopo Zenzeri
- Motor Learning, Assistive and Rehabilitation Robotics Laboratory, Robotics, Brain and Cognitive Sciences Department, Istituto Italiano di Tecnologia, Genoa, Italy
| | - Charmayne M L Hughes
- NeuroTech Laboratory, Health Equity Institute, San Francisco State University, San Francisco, CA, United States
| | - Francesca Marini
- Motor Learning, Assistive and Rehabilitation Robotics Laboratory, Robotics, Brain and Cognitive Sciences Department, Istituto Italiano di Tecnologia, Genoa, Italy
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18
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Wei B, Zhao X, Wang L, Hu B, Yu L, Tang H. Analysis of gear surface morphology based on gray level co-occurrence matrix and fractal dimension. PLoS One 2019; 14:e0223825. [PMID: 31639168 PMCID: PMC6804964 DOI: 10.1371/journal.pone.0223825] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2018] [Accepted: 09/30/2019] [Indexed: 11/18/2022] Open
Abstract
To investigate morphological characteristics and generation mechanism of the machined gears surface, image characteristics of machined surface morphology including profile roughness, fractal and textural characteristics were studied. the change of profile curves for the surface image is subject to the normal probability density function and the W-M function. The orientation angle of surface texture is 0°, the surface profile curves are the smoothest and have the most uniform, regular textures. When the texture orientation is 45° or 135°, the surface profile curves show large fluctuations, while surface image textures present the deepest grooves and are shown to be distributed most irregularly. Additionally, the influence mechanism of different grinding parameters on the morphological characteristics of machined surface was investigated. The quality of machined surfaces increased with the grinding speed while deteriorated with increasing radial, or axial, feed speeds.
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Affiliation(s)
- Bo Wei
- Institute of Computing Technology, Chinese Academy of Sciences, Beijing, China
- The First Research Institute of the Ministry of Public Security, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
- * E-mail:
| | - Xiaofang Zhao
- Institute of Computing Technology, Chinese Academy of Sciences, Beijing, China
| | - Long Wang
- Rocket Force University of Engineering, Xi'an, China
| | - Bin Hu
- Institute of Computing Technology, Chinese Academy of Sciences, Beijing, China
| | - Lei Yu
- Institute of Computing Technology, Chinese Academy of Sciences, Beijing, China
| | - Hongwei Tang
- Institute of Computing Technology, Chinese Academy of Sciences, Beijing, China
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19
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Samani M, Kordi Yoosefinejad A, Campos MH, de Lira CAB, Motealleh A. Changes in Knee Vastii Muscle Activity in Women with Patellofemoral Pain Syndrome During the Menstrual Cycle. PM R 2019; 12:382-390. [PMID: 31408276 DOI: 10.1002/pmrj.12239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Accepted: 07/29/2019] [Indexed: 11/12/2022]
Abstract
BACKGROUND Changes in hormonal levels during the menstrual cycle are known to affect muscle electromyographic (EMG) activity, but no studies have investigated the effect of hormonal changes on the EMG activity of muscles around the knee in patients with patellofemoral pain syndrome (PFPS). OBJECTIVE To evaluate the EMG activity of the vastus medialis obliquus (VMO) and vastus lateralis (VL) muscles during toe rise and heel rock tasks in different phases of the menstrual cycle in women with PFPS. DESIGN Cross sectional study. SETTING Rehabilitation Research Center at the School of Rehabilitation Sciences of Shiraz University of Medical Sciences. PARTICIPANTS Ten women with PFPS between 18 and 40 years of age. INTERVENTION Not applicable. MAIN OUTCOME MEASURES The VL/VMO amplitude ratio and differences between onset (onset VL-onset VMO) of vastii muscle activity were measured in the affected limb during rise and rock tasks in the follicular and ovulatory phases of the menstrual cycle. The signals were analyzed with MATLAB software. RESULTS During both tasks, there were no significant changes in onset differences in vastii muscles between the ovulatory and follicular phases. However, the amplitude ratio (VL/VMO) was significantly lower in the ovulatory phase compared to the follicular phase (P = .035 for rise tasks and .010 for rock tasks). CONCLUSION The menstrual cycle may affect some EMG parameters. These factors can be taken into account when planning sports and rehabilitation training programs.
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Affiliation(s)
- Mahbobeh Samani
- Department of Physical Therapy, School of Rehabilitation Sciences, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Amin Kordi Yoosefinejad
- Department of Physical Therapy, School of Rehabilitation Sciences, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Mario H Campos
- Faculty of Physical Education and Dance, Federal University of Goiás, Goiânia, Brazil
| | - Claudio A B de Lira
- Faculty of Physical Education and Dance, Federal University of Goiás, Goiânia, Brazil
| | - Alireza Motealleh
- Department of Physical Therapy, School of Rehabilitation Sciences, Shiraz University of Medical Sciences, Shiraz, Iran
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20
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A new fractal-based kinetic index to characterize gait deficits with application in stroke survivor functional mobility assessment. Biomed Signal Process Control 2019. [DOI: 10.1016/j.bspc.2018.09.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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21
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Pethick J, Winter SL, Burnley M. Fatigue reduces the complexity of knee extensor torque during fatiguing sustained isometric contractions. Eur J Sport Sci 2019; 19:1349-1358. [DOI: 10.1080/17461391.2019.1599450] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Jamie Pethick
- Endurance Research Group, School of Sport and Exercise Sciences, University of Kent, Kent, UK
| | - Samantha L. Winter
- Endurance Research Group, School of Sport and Exercise Sciences, University of Kent, Kent, UK
| | - Mark Burnley
- Endurance Research Group, School of Sport and Exercise Sciences, University of Kent, Kent, UK
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22
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Fatigue-Mediated Loss of Complexity is Contraction-Type Dependent in Vastus Lateralis Electromyographic Signals. Sports (Basel) 2019; 7:sports7040078. [PMID: 30986944 PMCID: PMC6524352 DOI: 10.3390/sports7040078] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Revised: 03/28/2019] [Accepted: 03/29/2019] [Indexed: 11/23/2022] Open
Abstract
The purpose of this study was to investigate the effect of fatigue status and contraction type on complexity of the surface electromyographic (sEMG) signal. Twelve females (mean age ± SD = 21.1 ± 1.4 years) performed three fatigue-inducing protocols that involved maximal concentric, eccentric, or isometric knee-extensor contractions over three non-consecutive sessions. Pre- and post-fatigue assessments were also completed each session and consisted of three maximal efforts for each type of contraction. Complexity of sEMG signals from the vastus lateralis was assessed using Sample Entropy (SampEn) and Detrended Fluctuation Analysis (DFA) as expressed using the scaling exponent α. The results showed that fatigue decreased (p < 0.05) sEMG complexity as indicated by decreased SampEn (non-fatigued: 1.57 ± 0.22 > fatigued: 1.46 ± 0.25) and increased DFA α (non-fatigued: 1.27 ± 0.26 < fatigued: 1.32 ± 0.23). In addition, sEMG complexity was different among contraction types as indicated by SampEn (concentric: 1.58 ± 0.22 > eccentric: 1.47 ± 0.27 and isometric: 1.50 ± 0.21) and DFA α (concentric: 1.27 ± 0.18 < isometric: 1.32 ± 0.18). Thus, these findings suggested sEMG complexity is affected by fatigue status and contraction type, with the degree of fatigue-mediated loss of complexity dependent on the type of contraction used to elicit fatigue.
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23
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Andrade-Guimarães AL, Aguiar-Oliveira MH, Salvatori R, Carvalho VO, Alvim-Pereira F, Daniel CRA, Brasileiro GAM, Santana-Ribeiro AA, Santos-Carvalho HA, Oliveira CRP, Vieira ER, Gois-Junior MB. Adult individuals with congenital, untreated, severe isolated growth hormone deficiency have satisfactory muscular function. Endocrine 2019; 63:112-119. [PMID: 30251164 DOI: 10.1007/s12020-018-1763-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2018] [Accepted: 09/11/2018] [Indexed: 12/24/2022]
Abstract
PURPOSE While growth hormone (GH) and the insulin-like growth factor type I (IGF-I) are known to exert synergistic actions on muscle anabolism, the consequences of prolonged GH deficiency (GHD) on muscle function have not been well defined. We have previously described a large cohort of subjects with isolated GHD (IGHD) caused by a mutation in the GH-releasing hormone receptor gene, with low serum levels of GH and IGF-I. The aim of this study was to assess muscular function in these IGHD subjects. METHODS A total of 31 GH-naïve IGHD (16 males) and 40 control (20 males) subjects, matched by age and degree of daily physical activity, were enrolled. Fat free mass was measured by bioelectrical impedance; muscle strength by dynamometry of handgrip, trunk extension, and knee extension; myoelectric activity and muscle fatigue by fractal dimension; conduction velocity in vastus medialis, rectus femoris, and vastus lateralis muscles by surface electromyography. RESULTS The IGHD group showed higher knee extension strength both when corrected for weight and fat free mass, and higher handgrip and trunk extension strength corrected by fat free mass. They also exhibit higher conduction velocity of the muscles vastus medialis, rectus femoris, and vastus lateralis, but lower free fat mass and myoelectric activity of the vastus medialis, rectus femoris and vastus lateralis. There were no differences between the two groups in fractal dimension in all studied muscles. CONCLUSION Individuals with untreated IGHD have better muscle strength parameters adjusted for weight and fat free mass than controls. They also exhibit greater peripheral resistance to fatigue, demonstrating satisfactory muscle function.
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Affiliation(s)
- Alana L Andrade-Guimarães
- Laboratory of Motor Control and Body Balance, Center for Health Science Research, Federal University of Sergipe, 49060-100, Sergipe, Brazil
- Department of Physical Therapy and Post-Graduate Program in Health Science, Federal University of Sergipe, The GREAT Group (GRupo de Estudos em ATividade física), Sergipe, Brazil
| | | | - Roberto Salvatori
- Division of Endocrinology, Diabetes and Metabolism, The Johns Hopkins University School of Medicine Baltimore, Baltimore, Maryland, 21287, USA.
| | - Vitor O Carvalho
- Department of Physical Therapy and Post-Graduate Program in Health Science, Federal University of Sergipe, The GREAT Group (GRupo de Estudos em ATividade física), Sergipe, Brazil
| | - Fabiano Alvim-Pereira
- Laboratory of Motor Control and Body Balance, Center for Health Science Research, Federal University of Sergipe, 49060-100, Sergipe, Brazil
| | - Carlos R Araújo Daniel
- Department of Statistic and Actuarial Sciences, Federal University of Sergipe, Aracaju, Sergipe, Brazil
| | - Giulliani A Moreira Brasileiro
- Laboratory of Motor Control and Body Balance, Center for Health Science Research, Federal University of Sergipe, 49060-100, Sergipe, Brazil
- Department of Physical Therapy and Post-Graduate Program in Health Science, Federal University of Sergipe, The GREAT Group (GRupo de Estudos em ATividade física), Sergipe, Brazil
| | - Ananda A Santana-Ribeiro
- Laboratory of Motor Control and Body Balance, Center for Health Science Research, Federal University of Sergipe, 49060-100, Sergipe, Brazil
| | - Hugo A Santos-Carvalho
- Laboratory of Motor Control and Body Balance, Center for Health Science Research, Federal University of Sergipe, 49060-100, Sergipe, Brazil
| | - Carla R P Oliveira
- Division of Endocrinology, Federal University of Sergipe, 49060-100, Aracaju, Sergipe, Brazil
| | - Edgar R Vieira
- Department of Physical Therapy and Neuroscience, Wertheims'College of Nursing and Health Science, Florida International University, Florida, USA
| | - Miburge B Gois-Junior
- Laboratory of Motor Control and Body Balance, Center for Health Science Research, Federal University of Sergipe, 49060-100, Sergipe, Brazil
- Department of Physical Therapy and Post-Graduate Program in Health Science, Federal University of Sergipe, The GREAT Group (GRupo de Estudos em ATividade física), Sergipe, Brazil
- Department of Physical Therapy and Neuroscience, Wertheims'College of Nursing and Health Science, Florida International University, Florida, USA
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Pethick J, Whiteaway K, Winter SL, Burnley M. Prolonged depression of knee-extensor torque complexity following eccentric exercise. Exp Physiol 2018; 104:100-111. [DOI: 10.1113/ep087295] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Accepted: 11/12/2018] [Indexed: 01/10/2023]
Affiliation(s)
- Jamie Pethick
- Endurance Research Group; School of Sport and Exercise Sciences; University of Kent; UK
| | - Katherine Whiteaway
- Endurance Research Group; School of Sport and Exercise Sciences; University of Kent; UK
| | - Samantha L. Winter
- Endurance Research Group; School of Sport and Exercise Sciences; University of Kent; UK
| | - Mark Burnley
- Endurance Research Group; School of Sport and Exercise Sciences; University of Kent; UK
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25
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Cury SS, Freire PP, Martinucci B, Dos Santos VC, de Oliveira G, Ferretti R, Dal-Pai-Silva M, Pacagnelli FL, Delella FK, Carvalho RF. Fractal dimension analysis reveals skeletal muscle disorganization in mdx mice. Biochem Biophys Res Commun 2018; 503:109-115. [PMID: 29852164 DOI: 10.1016/j.bbrc.2018.05.189] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Accepted: 05/28/2018] [Indexed: 11/24/2022]
Abstract
Duchenne Muscular Dystrophy (DMD) is characterized by muscle extracellular matrix disorganization due to the increased collagen deposition leading to fibrosis that significantly exacerbates disease progression. Fractal dimension analysis is a method that quantifies tissue/cellular disorganization and characterizes complex structures. The first objective of the present study was use fractal analysis to evaluate extracellular matrix disorganization in mdx mice soleus muscle. Next, we mimic a hyper-proliferation of fibrogenic cells by co-culturing NIH3T3 fibroblasts and C2C12 myoblasts to test whether fibroblasts induce disorganization in myoblast arrangement. Here, we show mdx presented high skeletal muscle disorganization as revealed by fractal analysis. Similarly, this method revealed that myoblasts co-cultured with fibroblast also presented cellular arrangement disorganization. We also reanalyzed skeletal muscle microarrays transcriptomic data from mdx and DMD patients that revealed transcripts related to extracellular matrix organization. This analysis also identified Osteoglycin, which was validated as a potential regulator of ECM organization in mdx dystrophic muscles. Our results demonstrate that fractal dimension is useful tool for the analysis of skeletal muscle disorganization in DMD and also reveal a fibroblast-myoblast cross-talk that contributes to "in vitro" myoblast disarrangement.
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Affiliation(s)
- Sarah Santiloni Cury
- Department of Morphology, Institute of Biosciences, São Paulo State University (UNESP), Botucatu, São Paulo, Brazil
| | - Paula Paccielli Freire
- Department of Morphology, Institute of Biosciences, São Paulo State University (UNESP), Botucatu, São Paulo, Brazil
| | - Bruno Martinucci
- Department of Morphology, Institute of Biosciences, São Paulo State University (UNESP), Botucatu, São Paulo, Brazil
| | | | - Grasieli de Oliveira
- Department of Morphology, Institute of Biosciences, São Paulo State University (UNESP), Botucatu, São Paulo, Brazil
| | - Renato Ferretti
- Department of Anatomy, Institute of Biosciences, São Paulo State University (UNESP), Botucatu, São Paulo, Brazil
| | - Maeli Dal-Pai-Silva
- Department of Morphology, Institute of Biosciences, São Paulo State University (UNESP), Botucatu, São Paulo, Brazil
| | - Francis Lopes Pacagnelli
- Department of Physiotherapy, University of Western São Paulo (UNOESTE), Presidente Prudente, São Paulo, Brazil
| | - Flávia Karina Delella
- Department of Morphology, Institute of Biosciences, São Paulo State University (UNESP), Botucatu, São Paulo, Brazil
| | - Robson Francisco Carvalho
- Department of Morphology, Institute of Biosciences, São Paulo State University (UNESP), Botucatu, São Paulo, Brazil.
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26
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Pethick J, Winter SL, Burnley M. Effects of ipsilateral and contralateral fatigue and muscle blood flow occlusion on the complexity of knee-extensor torque output in humans. Exp Physiol 2018; 103:956-967. [PMID: 29719079 DOI: 10.1113/ep086960] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Accepted: 04/25/2018] [Indexed: 01/15/2023]
Abstract
NEW FINDINGS What is the central question of this study? We addressed the question "what role do central and peripheral fatigue mechanisms play in the fatigue-induced loss of isometric torque complexity?" What is the main finding and its importance? When the contralateral limb is fatigued, the complexity of isometric torque output is unaffected even if the blood flow to the contralateral limb is occluded, which suggests that neither central fatigue nor afferent feedback from ischaemic muscle influences the complexity of torque output in an otherwise fresh muscle. ABSTRACT Neuromuscular fatigue reduces the temporal structure, or complexity, of torque output during muscular contractions. To determine whether the fatigue-induced loss of torque complexity could be accounted for by central or peripheral factors, nine healthy participants performed four experimental trials involving intermittent isometric contractions of the knee extensors at 50% of the maximal voluntary contraction torque. These trials involved: (i) two bouts of contractions to failure using the right leg separated by 3 min recovery (IPS); (ii) the same protocol but with cuff occlusion during the 3 min recovery (IPS-OCC); (iii) contractions of the left leg to failure, followed 1 min later by contractions of the right leg to failure (CONT); and (iv) the same protocol but with cuff occlusion applied to the left leg throughout both the recovery period and right leg contractions (CONT-OCC). Supramaximal electrical stimulation during maximal voluntary contractions was used to determine the degree of central and peripheral fatigue, whilst complexity was determined using approximate entropy (ApEn) and detrended fluctuation analysis α exponent (DFA α). Neuromuscular fatigue was consistently associated with a loss of torque complexity in all conditions [e.g. IPS bout 1, ApEn from (mean ± SD) 0.46 ± 0.14 to 0.12 ± 0.06 (P < 0.001)]. In IPS-OCC, occlusion abolished the recovery from fatigue, and torque complexity remained at the values observed at task failure in the preceding bout (IPS-OCC bout 2, first minute 0.14 ± 0.03, P < 0.001). Prior contralateral contractions, with or without blood flow occlusion, had no effect on torque complexity.
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Affiliation(s)
- Jamie Pethick
- Endurance Research Group, School of Sport and Exercise Sciences, University of Kent, Chatham Maritime, Kent, UK
| | - Samantha L Winter
- Endurance Research Group, School of Sport and Exercise Sciences, University of Kent, Chatham Maritime, Kent, UK
| | - Mark Burnley
- Endurance Research Group, School of Sport and Exercise Sciences, University of Kent, Chatham Maritime, Kent, UK
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Relationship between Isometric Muscle Force and Fractal Dimension of Surface Electromyogram. BIOMED RESEARCH INTERNATIONAL 2018; 2018:5373846. [PMID: 29736393 PMCID: PMC5875057 DOI: 10.1155/2018/5373846] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Revised: 02/01/2018] [Accepted: 02/11/2018] [Indexed: 11/17/2022]
Abstract
The relationship between fractal dimension of the surface electromyogram (sEMG) and the intensity of muscle contraction is still controversial in simulated and experimental conditions. To support the use of fractal analysis to investigate myoelectric fatigue, it is crucial to establish the interdependence between fractal dimension and muscle contraction intensity. We analyzed the behavior of fractal dimension, conduction velocity, mean frequency, and average rectified value in twenty-eight volunteers at nine levels of isometric force. sEMG was obtained using bidimensional arrays in the biceps brachii muscle. The values of fractal dimension and mean frequency increased with force unless a plateau was reached at 30% maximal voluntary contraction. Overall, our findings suggest that, above a certain level of force, the use of fractal dimension to evaluate the myoelectric manifestations of fatigue may be considered, regardless of muscle contraction intensity.
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Gea J, Sancho-Muñoz A, Chalela R. Nutritional status and muscle dysfunction in chronic respiratory diseases: stable phase versus acute exacerbations. J Thorac Dis 2018; 10:S1332-S1354. [PMID: 29928517 PMCID: PMC5989104 DOI: 10.21037/jtd.2018.02.66] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Accepted: 02/22/2018] [Indexed: 12/22/2022]
Abstract
Nutritional abnormalities are frequent in different chronic respiratory diseases such as chronic obstructive pulmonary disease (COPD), bronchiectasis, cystic fibrosis (CF), interstitial fibrosis and lung cancer, having important clinical consequences. However, nutritional abnormalities often remained underdiagnosed due to the relative lack of awareness of health professionals. Therefore, systematic anthropometry or even better, assessment of body composition, should be performed in all patients with chronic respiratory conditions, especially following exacerbation periods when malnutrition becomes more accentuated. Nutritional abnormalities very often include the loss of muscle mass, which is an important factor for the occurrence of muscle dysfunction. The latter can be easily detected with the specific assessment of muscle strength and endurance, and also negatively influences patients' quality of life and prognosis. Both nutritional abnormalities and muscle dysfunction result from the interaction of several factors, including tobacco smoking, low physical activity-sedentarism, systemic inflammation and the imbalance between energy supply and requirements, which essentially lead to a negative balance between protein breakdown and synthesis. Therapeutic approaches include improvements in lifestyle, nutritional supplementation and training. Anabolic drugs may be administered in some cases.
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Affiliation(s)
- Joaquim Gea
- Respiratory Medicine Department, Hospital del Mar (IMIM), DCEXS, Universitat Pompeu Fabra, CIBERES, ISCIII, Barcelona, Spain
| | - Antoni Sancho-Muñoz
- Respiratory Medicine Department, Hospital del Mar (IMIM), DCEXS, Universitat Pompeu Fabra, CIBERES, ISCIII, Barcelona, Spain
| | - Roberto Chalela
- Respiratory Medicine Department, Hospital del Mar (IMIM), DCEXS, Universitat Pompeu Fabra, CIBERES, ISCIII, Barcelona, Spain
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Belbasis A, Fuss FK. Muscle Performance Investigated With a Novel Smart Compression Garment Based on Pressure Sensor Force Myography and Its Validation Against EMG. Front Physiol 2018; 9:408. [PMID: 29725306 PMCID: PMC5917022 DOI: 10.3389/fphys.2018.00408] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Accepted: 04/04/2018] [Indexed: 11/21/2022] Open
Abstract
Muscle activity and fatigue performance parameters were obtained and compared between both a smart compression garment and the gold-standard, a surface electromyography (EMG) system during high-speed cycling in seven participants. The smart compression garment, based on force myography (FMG), comprised of integrated pressure sensors that were sandwiched between skin and garment, located on five thigh muscles. The muscle activity was assessed by means of crank cycle diagrams (polar plots) that displayed the muscle activity relative to the crank cycle. The fatigue was assessed by means of the median frequency of the power spectrum of the EMG signal; the fractal dimension (FD) of the EMG signal; and the FD of the pressure signal. The smart compression garment returned performance parameters (muscle activity and fatigue) comparable to the surface EMG. The major differences were that the EMG measured the electrical activity, whereas the pressure sensor measured the mechanical activity. As such, there was a phase shift between electrical and mechanical signals, with the electrical signals preceding the mechanical counterparts in most cases. This is specifically pronounced in high-speed cycling. The fatigue trend over the duration of the cycling exercise was clearly reflected in the fatigue parameters (FDs and median frequency) obtained from pressure and EMG signals. The fatigue parameter of the pressure signal (FD) showed a higher time dependency (R2 = 0.84) compared to the EMG signal. This reflects that the pressure signal puts more emphasis on the fatigue as a function of time rather than on the origin of fatigue (e.g., peripheral or central fatigue). In light of the high-speed activity results, caution should be exerted when using data obtained from EMG for biomechanical models. In contrast to EMG data, activity data obtained from FMG are considered more appropriate and accurate as an input for biomechanical modeling as they truly reflect the mechanical muscle activity. In summary, the smart compression garment based on FMG is a valid alternative to EMG-garments and provides more accurate results at high-speed activity (avoiding the electro-mechanical delay), as well as clearly measures the progress of muscle fatigue over time.
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Affiliation(s)
- Aaron Belbasis
- School of Engineering, RMIT University, Melbourne, VIC, Australia
| | - Franz Konstantin Fuss
- Smart Equipment Engineering and Wearable Technology Program, Centre for Design Innovation, Swinburne University of Technology, Melbourne, VIC, Australia
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Barbosa TM, Chen S, Morais JE, Costa MJ, Batalha N. The changes in classical and nonlinear parameters after a maximal bout to elicit fatigue in competitive swimming. Hum Mov Sci 2017; 58:321-329. [PMID: 29249572 DOI: 10.1016/j.humov.2017.12.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Revised: 12/05/2017] [Accepted: 12/10/2017] [Indexed: 10/18/2022]
Abstract
The aim was to assess the effect of fatigue on linear and nonlinear parameters in swimming. Twenty-four fitness-oriented swimmers performed a maximal bout of 100 m at front-crawl to elicit fatigue. Before (pre-) and immediately after (post-test) the bout, participants swam an all-out 25 m to derive the speed fluctuation (dv), approximate entropy (ApEn) and fractal dimension (FD) from the speed-time series collected by a speedo-meter. Swim speed was 10.85% slower in the post-test than in the pre-test (p < .001, η2 = 0.72). There was an effect of the fatigue on the dv with a moderate effect size. The dv increased shifting the 95CI band from 0.116-0.134 to 0.140-0.161. The ApEn showed non-significant variations between the pre- and post-test having the 95CI of pre- and post-test overlapped (pre: 0.659-0.700; post: 0.641-0.682). The FD showed as well a significant variation (the 95CI moved from 1.954-1.965 to 1.933-1.951). It can be concluded that in swimming there are changes in classical and nonlinear parameters under fatigue.
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Affiliation(s)
- Tiago M Barbosa
- Nanyang Technological University, Singapore; Polytechnic Institute of Bragança, Bragança, Portugal; Research Centre of Sports, Health and Human Development, CIDESD, STRONG Research Community, Vila Real, Portugal
| | - Simin Chen
- Nanyang Technological University, Singapore
| | - Jorge E Morais
- Polytechnic Institute of Bragança, Bragança, Portugal; Research Centre of Sports, Health and Human Development, CIDESD, STRONG Research Community, Vila Real, Portugal.
| | - Mário J Costa
- Polytechnic Institute of Guarda, Guarda, Portugal; Research Centre of Sports, Health and Human Development, CIDESD, STRONG Research Community, Vila Real, Portugal
| | - Nuno Batalha
- Department of Sport and Health, School of Science and Technology, University of Évora, Portugal; Research Centre of Sports, Health and Human Development, CIDESD, STRONG Research Community, Vila Real, Portugal
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Doll BD, Kirsch NA, Bao X, Dicianno BE, Sharma N. Dynamic optimization of stimulation frequency to reduce isometric muscle fatigue using a modified Hill-Huxley model. Muscle Nerve 2017; 57:634-641. [PMID: 28833237 DOI: 10.1002/mus.25777] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2016] [Revised: 08/07/2017] [Accepted: 08/12/2017] [Indexed: 11/06/2022]
Abstract
INTRODUCTION Optimal frequency modulation during functional electrical stimulation (FES) may minimize or delay the onset of FES-induced muscle fatigue. METHODS An offline dynamic optimization method, constrained to a modified Hill-Huxley model, was used to determine the minimum number of pulses that would maintain a constant desired isometric contraction force. RESULTS Six able-bodied participants were recruited for the experiments, and their quadriceps muscles were stimulated while they sat on a leg extension machine. The force-time (F-T) integrals and peak forces after the pulse train was delivered were found to be statistically significantly greater than the force-time integrals and peak forces obtained after a constant frequency train was delivered. DISCUSSION Experimental results indicated that the optimized pulse trains induced lower levels of muscle fatigue compared with constant frequency pulse trains. This could have a potential advantage over current FES methods that often choose a constant frequency stimulation train. Muscle Nerve 57: 634-641, 2018.
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Affiliation(s)
- Brian D Doll
- Bechtel Marine Propulsion Corporation, Pittsburgh, Pennsylvania, USA
| | | | - Xuefeng Bao
- Department of Mechanical Engineering and Materials Science, 636 Benedum Hall, University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, USA
| | - Brad E Dicianno
- Department of Physical Medicine and Rehabilitation Science, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Nitin Sharma
- Department of Mechanical Engineering and Materials Science, 636 Benedum Hall, University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, USA.,Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
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Muscle Fatigue Analysis of the Deltoid during Three Head-Related Static Isometric Contraction Tasks. ENTROPY 2017. [DOI: 10.3390/e19050221] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
This study aimed to investigate the fatiguing characteristics of muscle-tendon units (MTUs) within skeletal muscles during static isometric contraction tasks. The deltoid was selected as the target muscle and three head-related static isometric contraction tasks were designed to activate three heads of the deltoid in different modes. Nine male subjects participated in this study. Surface electromyography (SEMG) signals were collected synchronously from the three heads of the deltoid. The performances of five SEMG parameters, including root mean square (RMS), mean power frequency (MPF), the first coefficient of autoregressive model (ARC1), sample entropy (SE) and Higuchi’s fractal dimension (HFD), in quantification of fatigue, were evaluated in terms of sensitivity to variability ratio (SVR) and consistency firstly. Then, the HFD parameter was selected as the fatigue index for further muscle fatigue analysis. The experimental results demonstrated that the three deltoid heads presented different activation modes during three head-related fatiguing contractions. The fatiguing characteristics of the three heads were found to be task-dependent, and the heads kept in a relatively high activation level were more prone to fatigue. In addition, the differences in fatiguing rate between heads increased with the increase in load. The findings of this study can be helpful in better understanding the underlying neuromuscular control strategies of the central nervous system (CNS). Based on the results of this study, the CNS was thought to control the contraction of the deltoid by taking the three heads as functional units, but a certain synergy among heads might also exist to accomplish a contraction task.
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Mitsuyama A, Takahashi T, Ueno T. Effects of teeth clenching on the soleus H reflex during lower limb muscle fatigue. J Prosthodont Res 2017; 61:202-209. [DOI: 10.1016/j.jpor.2016.05.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Revised: 05/11/2016] [Accepted: 05/28/2016] [Indexed: 11/25/2022]
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Beretta-Piccoli M, D’Antona G, Zampella C, Barbero M, Clijsen R, Cescon C. Test-retest reliability of muscle fiber conduction velocity and fractal dimension of surface EMG during isometric contractions. Physiol Meas 2017; 38:616-630. [DOI: 10.1088/1361-6579/aa614c] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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Hohenauer E, Cescon C, Deliens T, Clarys P, Clijsen R. The effect of local skin cooling before a sustained, submaximal isometric contraction on fatigue and isometric quadriceps femoris performance: A randomized controlled trial. J Therm Biol 2017; 65:88-94. [PMID: 28343582 DOI: 10.1016/j.jtherbio.2017.02.017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Revised: 02/24/2017] [Accepted: 02/24/2017] [Indexed: 10/20/2022]
Abstract
The central- and peripheral mechanisms by which heat strain limits physical performance are not fully elucidated. Nevertheless, pre-cooling is often used in an attempt to improve subsequent performance. This study compared the effects of pre-cooling vs. a pre-thermoneutral application on central- and peripheral fatigue during 60% of isometric maximum voluntary contraction (MVC) of the right quadriceps femoris muscle. Furthermore, the effects between a pre-cooling and a pre-thermoneutral application on isometric MVC of the right quadriceps femoris muscle and subjective ratings of perceived exertion (RPE) were investigated. In this randomized controlled trial, 18 healthy adults voluntarily participated. The participants received either a cold (experimental) application (+8°C) or a thermoneutral (control) application (+32°C) for 20min on their right thigh (one cuff). After the application, central (fractal dimension - FD) and peripheral (muscle fiber conduction velocity - CV) fatigue was estimated using sEMG parameters during 60% of isometric MVC. Surface EMG signals were detected from the vastus medialis and lateralis using bidimensional arrays. Immediately after the submaximal contraction, isometric MVC and RPE were assessed. Participants receiving the cold application were able to maintain a 60% isometric MVC significantly longer when compared to the thermoneutral group (mean time: 78 vs. 46s; p=0.04). The thermoneutral application had no significant impact on central fatigue (p>0.05) compared to the cold application (p=0.03). However, signs of peripheral fatigue were significantly higher in the cold group compared to the thermoneutral group (p=0.008). Pre-cooling had no effect on isometric MVC of the right quadriceps muscle and ratings of perceived exertion. Pre-cooling attenuated central fatigue and led to significantly longer submaximal contraction times compared to the pre-thermoneutral application. These findings support the use of pre-cooling procedures prior to submaximal exercises of the quadriceps muscle compared to pre-thermoneutral applications.
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Affiliation(s)
- Erich Hohenauer
- Department of Business Economics, Health and Social Care, University of Applied Sciences and Arts of Southern Switzerland, Landquart, Switzerland; University College Physiotherapy, Thim van der Laan, Landquart, Switzerland; Department of Movement and Sport Sciences, Vrije Universiteit Brussel, Brussels, Belgium.
| | - Corrado Cescon
- Department of Business Economics, Health and Social Care, University of Applied Sciences and Arts of Southern Switzerland, Manno, Switzerland.
| | - Tom Deliens
- Department of Movement and Sport Sciences, Vrije Universiteit Brussel, Brussels, Belgium.
| | - Peter Clarys
- Department of Movement and Sport Sciences, Vrije Universiteit Brussel, Brussels, Belgium.
| | - Ron Clijsen
- Department of Business Economics, Health and Social Care, University of Applied Sciences and Arts of Southern Switzerland, Landquart, Switzerland; University College Physiotherapy, Thim van der Laan, Landquart, Switzerland; Department of Movement and Sport Sciences, Vrije Universiteit Brussel, Brussels, Belgium.
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Meduri F, Beretta-Piccoli M, Calanni L, Segreto V, Giovanetti G, Barbero M, Cescon C, D’Antona G. Inter-Gender sEMG Evaluation of Central and Peripheral Fatigue in Biceps Brachii of Young Healthy Subjects. PLoS One 2016; 11:e0168443. [PMID: 28002429 PMCID: PMC5176311 DOI: 10.1371/journal.pone.0168443] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Accepted: 12/01/2016] [Indexed: 11/19/2022] Open
Abstract
Purpose The purpose of the present study was to evaluate inter-arm and inter-gender differences in fractal dimension (FD) and conduction velocity (CV) obtained from multichannel surface electromyographic (sEMG) recordings during sustained fatiguing contractions of the biceps brachii. Methods A total of 20 recreationally active males (24±6 years) and 18 recreationally active females (22±9 years) performed two isometric contractions at 120 degrees elbow joint angle: (1) at 20% maximal voluntary contraction (MVC) for 90 s, and (2) at 60% MVC until exhaustion the time to perform the task has been measured. Signals from sEMG were detected from the biceps brachii using bidimensional arrays of 64 electrodes and initial values and rate of change of CV and FD of the sEMG signal were calculated. Results No difference between left and right sides and no statistically significant interaction effect of sides with gender were found for all parameters measured. A significant inter-gender difference was found for MVC (p<0.0001). Initial values of CV were higher in females than in males at both force levels (20% MCV: p<0.0001; 60% MCV: p<0.05) whereas a lower initial estimate of FD was observed in females compared to males (20% MCV: p<0.05; 60% MCV: p<0.0001). No difference in CV and FD slopes was found at 20% MVC between genders. At 60% MVC significantly lower CV and FD slopes (CV and FD: p<0.05) and a more protracted time to exhaustion were found in females than in males (p<0.0001). When considering time to exhaustion at both levels of contraction no difference in percentage change (Δ%) of CV and FD slopes was found between genders (p>0.05). During the sustained 60% MVC no statistical correlation was found between MVC and CV or FD initial estimates nor between MVC and CV or FD slopes both in males and females whereas. A significant positive correlation between CV and FD slopes was found in both genders (males: r = 0,61; females: r = 0,55). Conclusions Fatigue determines changes in FD and CV values in biceps brachii during sustained contractions at 60% MVC. In particular males show greater increase in the rate of change of CV and FD than females whereas no difference in percentage change of these sEMG descriptors of fatigue was found. A significant correlation between FD and CV slopes found in both genders highlights that central and peripheral myoelectric components of fatigue may interact during submaximal isometric contractions.
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Affiliation(s)
- Federico Meduri
- Department of Public Health, Molecular and Forensic Medicine, and Sport Medicine Centre Voghera, University of Pavia, Pavia, Italy
| | - Matteo Beretta-Piccoli
- Rehabilitation Research Laboratory 2rLab, Department of Business Economics, Health and Social Care, University of Applied Sciences and Arts of Southern Switzerland, Manno, Switzerland
| | - Luca Calanni
- Department of Public Health, Molecular and Forensic Medicine, and Sport Medicine Centre Voghera, University of Pavia, Pavia, Italy
| | - Valentina Segreto
- Department of Public Health, Molecular and Forensic Medicine, and Sport Medicine Centre Voghera, University of Pavia, Pavia, Italy
| | - Giuseppe Giovanetti
- Department of Public Health, Molecular and Forensic Medicine, and Sport Medicine Centre Voghera, University of Pavia, Pavia, Italy
| | - Marco Barbero
- Rehabilitation Research Laboratory 2rLab, Department of Business Economics, Health and Social Care, University of Applied Sciences and Arts of Southern Switzerland, Manno, Switzerland
| | - Corrado Cescon
- Rehabilitation Research Laboratory 2rLab, Department of Business Economics, Health and Social Care, University of Applied Sciences and Arts of Southern Switzerland, Manno, Switzerland
| | - Giuseppe D’Antona
- Department of Public Health, Molecular and Forensic Medicine, and Sport Medicine Centre Voghera, University of Pavia, Pavia, Italy
- * E-mail:
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Solianik R, Kreivėnaitė L, Streckis V, Mickevičienė D, Skurvydas A. Effects of age and sex on fatigability and recovery from a sustained maximal isometric voluntary contraction. J Electromyogr Kinesiol 2016; 32:61-69. [PMID: 28040567 DOI: 10.1016/j.jelekin.2016.12.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Revised: 11/03/2016] [Accepted: 12/08/2016] [Indexed: 10/20/2022] Open
Abstract
The aim was to assess the effects of sex and age on fatigability and recovery from sustained maximal voluntary contraction (MVC) of the knee extensor muscles. The central (central activation ratio (CAR) and electrical activity amplitude) and peripheral (electrically evoked torque and muscle contractile properties) factors contributing to fatigue and recovery of 24 young adults (12 males) aged 23.2±3.6years and 20 older adults (12 males) aged 70.6±4.4years were compared. The increase in central and peripheral fatigue was greater (p⩽0.01) in the young adults vs the older adults. Sex differences (p=0.002) regarding MVC were attributed to the greater (p<0.01) peripheral fatigue of males vs females. The recovery rate of MVC was greater (p<0.001) in the young adults vs the older adults, with no sex effect. The recovery of MVC was correlated with the CAR in older adults (p=0.001). Thus, the greater endurance observed with age is caused by differences in central and peripheral mechanisms, whereas the greater endurance in females is caused by a difference in a mechanism located within the muscle. The impaired recovery from fatigue in older adults relied more on the recovery of central factors.
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Affiliation(s)
- Rima Solianik
- Institute of Sports Science and Innovations, Lithuanian Sports University, Sporto str. 6, Kaunas, Lithuania.
| | - Lina Kreivėnaitė
- Institute of Sports Science and Innovations, Lithuanian Sports University, Sporto str. 6, Kaunas, Lithuania
| | - Vytautas Streckis
- Institute of Sports Science and Innovations, Lithuanian Sports University, Sporto str. 6, Kaunas, Lithuania
| | - Dalia Mickevičienė
- Institute of Sports Science and Innovations, Lithuanian Sports University, Sporto str. 6, Kaunas, Lithuania
| | - Albertas Skurvydas
- Institute of Sports Science and Innovations, Lithuanian Sports University, Sporto str. 6, Kaunas, Lithuania
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Lower fatigability of locomotor than non-locomotor muscles in endurance runners. SPORT SCIENCES FOR HEALTH 2016. [DOI: 10.1007/s11332-016-0297-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Gea J, Casadevall C, Pascual S, Orozco-Levi M, Barreiro E. Clinical management of chronic obstructive pulmonary disease patients with muscle dysfunction. J Thorac Dis 2016; 8:3379-3400. [PMID: 28066619 DOI: 10.21037/jtd.2016.11.105] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Muscle dysfunction is frequently observed in chronic obstructive pulmonary disease (COPD) patients, contributing to their exercise limitation and a worsening prognosis. The main factor leading to limb muscle dysfunction is deconditioning, whereas respiratory muscle dysfunction is mostly the result of pulmonary hyperinflation. However, both limb and respiratory muscles are also influenced by other negative factors, including smoking, systemic inflammation, nutritional abnormalities, exacerbations and some drugs. Limb muscle weakness is generally diagnosed through voluntary isometric maneuvers such as handgrip or quadriceps muscle contraction (dynamometry); while respiratory muscle loss of strength is usually recognized through a decrease in maximal static pressures measured at the mouth. Both types of measurements have validated reference values. Respiratory muscle strength can also be evaluated determining esophageal, gastric and transdiaphragmatic maximal pressures although there is a lack of widely accepted reference equations. Non-volitional maneuvers, obtained through electrical or magnetic stimulation, can be employed in patients unable to cooperate. Muscle endurance can also be assessed, generally using repeated submaximal maneuvers until exhaustion, but no validated reference values are available yet. The treatment of muscle dysfunction is multidimensional and includes improvement in lifestyle habits (smoking abstinence, healthy diet and a good level of physical activity, preferably outside), nutritional measures (diet supplements and occasionally, anabolic drugs), and different modalities of general and muscle training.
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Affiliation(s)
- Joaquim Gea
- Servei de Pneumologia, Hospital del Mar - IMIM, Experimental Sciences and Health Department (DCEXS), Universitat Pompeu Fabra, CIBERES, ISC III, Barcelona, Catalonia, Spain
| | - Carme Casadevall
- Servei de Pneumologia, Hospital del Mar - IMIM, Experimental Sciences and Health Department (DCEXS), Universitat Pompeu Fabra, CIBERES, ISC III, Barcelona, Catalonia, Spain
| | - Sergi Pascual
- Servei de Pneumologia, Hospital del Mar - IMIM, Experimental Sciences and Health Department (DCEXS), Universitat Pompeu Fabra, CIBERES, ISC III, Barcelona, Catalonia, Spain
| | - Mauricio Orozco-Levi
- Department of Respiratory, Cardiovascular Foundation from Colombia Floridablanca, Santander, Colombia, CIBERES, ISC III, Barcelona, Catalonia, Spain
| | - Esther Barreiro
- Servei de Pneumologia, Hospital del Mar - IMIM, Experimental Sciences and Health Department (DCEXS), Universitat Pompeu Fabra, CIBERES, ISC III, Barcelona, Catalonia, Spain
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Mesin L, Dardanello D, Rainoldi A, Boccia G. Motor unit firing rates and synchronisation affect the fractal dimension of simulated surface electromyogram during isometric/isotonic contraction of vastus lateralis muscle. Med Eng Phys 2016; 38:1530-1533. [PMID: 27743780 DOI: 10.1016/j.medengphy.2016.09.022] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Revised: 09/13/2016] [Accepted: 09/26/2016] [Indexed: 11/29/2022]
Abstract
During fatiguing contractions, many adjustments in motor units behaviour occur: decrease in muscle fibre conduction velocity; increase in motor units synchronisation; modulation of motor units firing rate; increase in variability of motor units inter-spike interval. We simulated the influence of all these adjustments on synthetic EMG signals in isometric/isotonic conditions. The fractal dimension of the EMG signal was found mainly influenced by motor units firing behaviour, being affected by both firing rate and synchronisation level, and least affected by muscle fibre conduction velocity. None of the calculated EMG indices was able to discriminate between firing rate and motor units synchronisation.
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Affiliation(s)
- Luca Mesin
- Mathematical Biology and Physiology, Dipartimento di Elettronica e Telecomunicazioni, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Turin, Italy
| | - Davide Dardanello
- Motor Science Research Center, School of Exercise and Sport Sciences, SUISM, Department of Medical Sciences, University of Turin, Piazza Bernini 12, 10143 Torino, Italy
| | - Alberto Rainoldi
- Motor Science Research Center, School of Exercise and Sport Sciences, SUISM, Department of Medical Sciences, University of Turin, Piazza Bernini 12, 10143 Torino, Italy
| | - Gennaro Boccia
- Motor Science Research Center, School of Exercise and Sport Sciences, SUISM, Department of Medical Sciences, University of Turin, Piazza Bernini 12, 10143 Torino, Italy; CeRiSM Research Center 'Sport, Mountain, and Health', Via Matteo del Ben 5/B, 38068 Rovereto (TN), Italy .
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Li L, Shin H, Li X, Li S, Zhou P. Localized Electrical Impedance Myography of the Biceps Brachii Muscle during Different Levels of Isometric Contraction and Fatigue. SENSORS 2016; 16:s16040581. [PMID: 27110795 PMCID: PMC4851095 DOI: 10.3390/s16040581] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Revised: 04/11/2016] [Accepted: 04/17/2016] [Indexed: 11/16/2022]
Abstract
This study assessed changes in electrical impedance myography (EIM) at different levels of isometric muscle contraction as well as during exhaustive exercise at 60% maximum voluntary contraction (MVC) until task failure. The EIM was performed on the biceps brachii muscle of 19 healthy subjects. The results showed that there was a significant difference between the muscle resistance (R) measured during the isometric contraction and when the muscle was completely relaxed. Post hoc analysis shows that the resistance increased at higher contractions (both 60% MVC and MVC), however, there were no significant changes in muscle reactance (X) during the isometric contractions. The resistance also changed during different stages of the fatigue task and there were significant decreases from the beginning of the contraction to task failure as well as between task failure and post fatigue rest. Although our results demonstrated an increase in resistance during isometric contraction, the changes were within 10% of the baseline value. These changes might be related to the modest alterations in muscle architecture during a contraction. The decrease in resistance seen with muscle fatigue may be explained by an accumulation of metabolites in the muscle tissue.
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Affiliation(s)
- Le Li
- Department of Rehabilitation Medicine, the First Affiliated Hospital, Sun Yat-sen University, Guangzhou 510080, China.
- Department of Physical Medicine and Rehabilitation, University of Texas Health Science Center at Houston; TIRR Memorial Hermann Research Center, Houston, TX 77030, USA.
| | - Henry Shin
- Department of Physical Medicine and Rehabilitation, University of Texas Health Science Center at Houston; TIRR Memorial Hermann Research Center, Houston, TX 77030, USA.
| | - Xiaoyan Li
- Department of Physical Medicine and Rehabilitation, University of Texas Health Science Center at Houston; TIRR Memorial Hermann Research Center, Houston, TX 77030, USA.
| | - Sheng Li
- Department of Physical Medicine and Rehabilitation, University of Texas Health Science Center at Houston; TIRR Memorial Hermann Research Center, Houston, TX 77030, USA.
| | - Ping Zhou
- Department of Physical Medicine and Rehabilitation, University of Texas Health Science Center at Houston; TIRR Memorial Hermann Research Center, Houston, TX 77030, USA.
- Guangdong Work Injury Rehabilitation Center, Guangzhou 510440, China.
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McManus L, Hu X, Rymer WZ, Suresh NL, Lowery MM. Muscle fatigue increases beta-band coherence between the firing times of simultaneously active motor units in the first dorsal interosseous muscle. J Neurophysiol 2016; 115:2830-9. [PMID: 26984420 DOI: 10.1152/jn.00097.2016] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Accepted: 03/15/2016] [Indexed: 11/22/2022] Open
Abstract
Synchronization between the firing times of simultaneously active motor units (MUs) is generally assumed to increase during fatiguing contractions. To date, however, estimates of MU synchronization have relied on indirect measures, derived from surface electromyographic (EMG) interference signals. This study used intramuscular coherence to investigate the correlation between MU discharges in the first dorsal interosseous muscle during and immediately following a submaximal fatiguing contraction, and after rest. Coherence between composite MU spike trains, derived from decomposed surface EMG, were examined in the delta (1-4 Hz), alpha (8-12 Hz), beta (15-30 Hz), and gamma (30-60 Hz) frequency band ranges. A significant increase in MU coherence was observed in the delta, alpha, and beta frequency bands postfatigue. In addition, wavelet coherence revealed a tendency for delta-, alpha-, and beta-band coherence to increase during the fatiguing contraction, with subjects exhibiting low initial coherence values displaying the greatest relative increase. This was accompanied by an increase in MU short-term synchronization and a decline in mean firing rate of the majority of MUs detected during the sustained contraction. A model of the motoneuron pool and surface EMG was used to investigate factors influencing the coherence estimate. Simulation results indicated that changes in motoneuron inhibition and firing rates alone could not directly account for increased beta-band coherence postfatigue. The observed increase is, therefore, more likely to arise from an increase in the strength of correlated inputs to MUs as the muscle fatigues.
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Affiliation(s)
- Lara McManus
- University College Dublin, Belfield, Dublin, Ireland;
| | - Xiaogang Hu
- Joint Department of Biomedical Engineering, University of North Carolina-Chapel Hill and North Carolina State University, Chapel Hill, North Carolina
| | - William Z Rymer
- Rehabilitation Institute of Chicago, Chicago, Illinois; and Northwestern University, Evanston, Illinois
| | - Nina L Suresh
- Rehabilitation Institute of Chicago, Chicago, Illinois; and
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Boccia G, Dardanello D, Beretta-Piccoli M, Cescon C, Coratella G, Rinaldo N, Barbero M, Lanza M, Schena F, Rainoldi A. Muscle fiber conduction velocity and fractal dimension of EMG during fatiguing contraction of young and elderly active men. Physiol Meas 2015; 37:162-74. [DOI: 10.1088/0967-3334/37/1/162] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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