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Kwak M, Succi PJ, Benitez B, Mitchinson C, Samaan MA, Abel MG, Bergstrom HC. Comparison of Force, Neuromuscular, and Metabolic Responses During Sustained, Isometric Handgrip Holds to Failure Anchored to Low and High Perceptual Intensities in Men: An Exploratory Study. J Strength Cond Res 2024; 38:e405-e416. [PMID: 39072661 PMCID: PMC11296493 DOI: 10.1519/jsc.0000000000004812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/30/2024]
Abstract
ABSTRACT Kwak, M, Succi, PJ, Benitez, B, Mitchinson, C, Samaan, MA, Abel, MG, and Bergstrom, HC. Comparison of force, neuromuscular, and metabolic responses during sustained, isometric handgrip holds to failure anchored to low and high perceptual intensities in men: An exploratory study. J Strength Cond Res 38(8): e405-e416, 2024-This study examined the responses of force alterations, relative to critical force (CF), neuromuscular parameters, and muscle oxygenation (SmO2) for isometric handgrip holds to failure (HTF) anchored to ratings of perceived exertion (RPE) of 3 and 7. Twelve men completed pre-maximal voluntary isometric contractions (pre-MVIC), submaximal HTF at 4 percentages of pre-MVIC, HTF at RPE = 3 and 7, and post-MVIC. Mechanomyograpic (MMG) signals and SmO2 were recorded during the RPE HTF. Analyses included paired-samples t-tests and repeated-measures ANOVAs at an alpha level of p ≤ 0.05. Time to task failure was not different between RPE 3 (478.7 ± 196.6 s) and RPE 7 (495.8 ± 173.8 s). Performance fatigability (PF) and MMG amplitude (AMP) were greater for RPE 7 (PF: 37.9 ± 12.9%; MMG AMP: 15.7 ± 7.4% MVIC) than RPE 3 (PF: 30.0 ± 14.5%; MMG AMP: 10.2 ± 6.5% MVIC), but MMG mean power frequency (MPF) was greater for RPE 3 (146.2 ± 31.1% MVIC) than RPE 7 (128.8 ± 23.0% MVIC). There were RPE-dependent decreases in force (p ≤ 0.01) across 3 discernable phases during the HTF. There were decreases in MMG AMP across time for both RPEs, but there were no significant changes in MMG MPF or SmO2. There were overall similar motor unit control strategies and local metabolic demand between RPEs. The majority of the HTF performed below CF at RPE 3 and 7 indicated CF did not reflect the highest sustainable force. When prescribing isometric exercise anchored to RPE, practitioners should be aware of the magnitude of force loss and relative intensity of the task to be sure desired training loads are met.
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Affiliation(s)
- Minyoung Kwak
- Department of Kinesiology and Health Promotion, The University of Kentucky, Lexington, KY, USA
| | - Pasquale J. Succi
- Department of Kinesiology and Health Promotion, The University of Kentucky, Lexington, KY, USA
| | - Brian Benitez
- Department of Kinesiology and Health Promotion, The University of Kentucky, Lexington, KY, USA
| | - Clara Mitchinson
- Department of Kinesiology and Health Promotion, The University of Kentucky, Lexington, KY, USA
| | - Michael A. Samaan
- Department of Kinesiology and Health Promotion, The University of Kentucky, Lexington, KY, USA
| | - Mark G. Abel
- Department of Kinesiology and Health Promotion, The University of Kentucky, Lexington, KY, USA
| | - Haley C. Bergstrom
- Department of Kinesiology and Health Promotion, The University of Kentucky, Lexington, KY, USA
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Cornejo-Daza PJ, Sánchez-Valdepeñas J, Páez-Maldonado J, Rodiles-Guerrero L, Boullosa D, León-Prados JA, Wernbom M, Pareja-Blanco F. Acute Responses to Traditional and Cluster-Set Squat Training With and Without Blood Flow Restriction. J Strength Cond Res 2024; 38:1401-1412. [PMID: 38780903 PMCID: PMC11286160 DOI: 10.1519/jsc.0000000000004820] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2024]
Abstract
ABSTRACT Cornejo-Daza, PJ, Sánchez-Valdepeñas, J, Páez-Maldonado, J, Rodiles-Guerrero, L, Boullosa, D, León-Prados, JA, Wernbom, M, and Pareja-Blanco, F. Acute responses to traditional and cluster-set squat training with and without blood flow restriction. J Strength Cond Res 38(8): 1401-1412, 2024-To compare the acute responses to different set configurations (cluster [CLU] vs. traditional [TRA]) under distinct blood flow conditions (free vs. restricted) in full-squat (SQ). Twenty resistance-trained males performed 4 protocols that differed in the set configuration (TRA: continuous repetitions; vs. CLU: 30 seconds of rest every 2 repetitions) and in the blood flow condition (FF: free-flow; vs. blood flow restriction [BFR]: 50% of arterial occlusion pressure). The relative intensity (60% 1RM), volume (3 sets of 8 repetitions), and resting time (2 minutes) were equated. Mean propulsive force (MPF), velocity (MPV) and power (MPP), and electromyography (EMG) parameters were recorded during each repetition. Tensiomyography (TMG), blood lactate, countermovement jump (CMJ) height, maximal voluntary isometric contraction, in SQ, and movement velocity against the load that elicited a 1 m·s -1 velocity at baseline (V1-load) in SQ were assessed at pre- and post-exercise. The CLU protocols allowed a better maintenance of MPF, MPV, MPP, and EMG median frequency during the exercise compared to TRA (clu-time interaction, p < 0.05). The TRA protocols experienced greater impairments post-exercise in TMG- and EMG-derived variables (clu-time interaction, p < 0.05) and SQ and CMJ performance (clu-time interaction, p = 0.08 and p < 0.05, respectively), as well as higher blood lactate concentrations (clu-time interaction, p < 0.001) than CLU. Moreover, BFR displayed decreases in TMG variables (bfr-time interaction, p < 0.01), but BFR-CLU resulted in the greatest reduction in twitch contraction time ( p < 0.001). Cluster sets reduced fatigue during and after the training session and BFR exacerbated impairments in muscle mechanical properties; however, the combination of both could improve contraction speed after exercise.
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Affiliation(s)
- Pedro J. Cornejo-Daza
- Science Based Training Research Group. Department of Sports and Computers Sciences. Universidad Pablo de Olavide, Seville, Spain
- Faculty of Sport Sciences, Department of Sports and Computers Sciences, Universidad Pablo de Olavide, Seville, Spain
- Department of Human Motor and Sports Performance, University of Seville, Seville, Spain
| | - Juan Sánchez-Valdepeñas
- Science Based Training Research Group. Department of Sports and Computers Sciences. Universidad Pablo de Olavide, Seville, Spain
- Faculty of Sport Sciences, Department of Sports and Computers Sciences, Universidad Pablo de Olavide, Seville, Spain
| | - Jose Páez-Maldonado
- Science Based Training Research Group. Department of Sports and Computers Sciences. Universidad Pablo de Olavide, Seville, Spain
- Faculty of Sport Sciences, University of Seville, Osuna, Spain
| | - Luis Rodiles-Guerrero
- Science Based Training Research Group. Department of Sports and Computers Sciences. Universidad Pablo de Olavide, Seville, Spain
- Department of Human Motor and Sports Performance, University of Seville, Seville, Spain
| | - Daniel Boullosa
- Faculty of Physical Activity and Sports Sciences, Universidad de León, León, Spain
- Integrated Institute of Health, Federal University of Mato Grosso do Sul, Campo Grande, Brazil
- College of Healthcare Sciences, James Cook University, Townsville, Australia; and
| | - Juan A. León-Prados
- Science Based Training Research Group. Department of Sports and Computers Sciences. Universidad Pablo de Olavide, Seville, Spain
- Faculty of Sport Sciences, Department of Sports and Computers Sciences, Universidad Pablo de Olavide, Seville, Spain
| | - Mathias Wernbom
- Integrated Institute of Health, Federal University of Mato Grosso do Sul, Campo Grande, Brazil
| | - Fernando Pareja-Blanco
- Science Based Training Research Group. Department of Sports and Computers Sciences. Universidad Pablo de Olavide, Seville, Spain
- Faculty of Sport Sciences, Department of Sports and Computers Sciences, Universidad Pablo de Olavide, Seville, Spain
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Páez-Maldonado JA, Cornejo-Daza P, Sánchez-Valdepeñas J, Sánchez-Moreno M, Yuzo-Nakamura F, Pareja-Blanco F, Ortega-Becerra M. Acute Metabolic Response, Neuromuscular Activity, and Mechanical Performance to Different Set. Int J Sports Med 2024. [PMID: 39074809 DOI: 10.1055/a-2179-3817] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/31/2024]
Abstract
The aim of this study was to examine the acute metabolic response, neuromuscular activity, and mechanical performance of different set configurations in bench-press (BP). Twenty-two resistance-trained men performed three resistance exercise protocols consisting of 3 x 12 BP repetitions at 60% 1RM, with 4 minutes of rest between sets, but with different set configurations: (a) traditional set (TS), without rest within the set; (b) cluster-6 (CS6), with 30-second intraset rest after the sixth repetition in each set; and (c) cluster-2 (CS2), with 30-second intraset rest every two repetitions. Mean propulsive force (MPF), velocity (MPV), power (MPP), and electromyography (EMG) values were recorded for each repetition. Blood lactate, maximal voluntary isometric BP contraction, and dynamic strength in BP were assessed pre- and post-exercise. The CS2 protocol resulted in greater mechanical performance (i. e. MPF, MPV, and MPP) and lower alterations of EMG parameters (i. e. root mean square and median frequency) during the exercise compared to CS6 and TS (TS
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Affiliation(s)
- José Antonio Páez-Maldonado
- University of Osuna (Centre attached to the University of Seville), Osuna, Spain
- Science Based Training Research Group, Department of Sports and Computer Sciences,Universidad Pablo de Olavide, 41013 Seville, Spain
| | - PedroJesús Cornejo-Daza
- Science Based Training Research Group, Department of Sports and Computer Sciences,Universidad Pablo de Olavide, 41013 Seville, Spain
- Faculty of Sport Sciences. Department of Sports and Computers Sciences. Universidad Pablo de Olavide, Seville, Spain
| | - Juan Sánchez-Valdepeñas
- Science Based Training Research Group, Department of Sports and Computer Sciences,Universidad Pablo de Olavide, 41013 Seville, Spain
- Faculty of Sport Sciences. Department of Sports and Computers Sciences. Universidad Pablo de Olavide, Seville, Spain
| | - Miguel Sánchez-Moreno
- Science Based Training Research Group, Department of Sports and Computer Sciences,Universidad Pablo de Olavide, 41013 Seville, Spain
- Department of Physical Education and Sports. University of Seville, Seville, Spain
| | - Fábio Yuzo-Nakamura
- Research Center in Sports Sciences, Health Sciences and Human Development (CIDESD), University Institute of Maia (ISMAI), Maia, Portugal
| | - Fernando Pareja-Blanco
- Science Based Training Research Group, Department of Sports and Computer Sciences,Universidad Pablo de Olavide, 41013 Seville, Spain
- Faculty of Sport Sciences. Department of Sports and Computers Sciences. Universidad Pablo de Olavide, Seville, Spain
| | - Manuel Ortega-Becerra
- Science Based Training Research Group, Department of Sports and Computer Sciences,Universidad Pablo de Olavide, 41013 Seville, Spain
- Faculty of Sport Sciences. Department of Sports and Computers Sciences. Universidad Pablo de Olavide, Seville, Spain
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Kotikangas J, Walker S, Peltonen H, Häkkinen K. Time Course of Neuromuscular Fatigue During Different Resistance Exercise Loadings in Power Athletes, Strength Athletes, and Nonathletes. J Strength Cond Res 2024; 38:1231-1242. [PMID: 38900602 DOI: 10.1519/jsc.0000000000004769] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/22/2024]
Abstract
ABSTRACT Kotikangas, J, Walker, S, Peltonen, H, and Häkkinen, K. Time course of neuromuscular fatigue during different resistance exercise loadings in power athletes, strength athletes, and nonathletes. J Strength Cond Res 38(7): 1231-1242, 2024-Training background may affect the progression of fatigue and neuromuscular strategies to compensate for fatigue during resistance exercises. Thus, our aim was to examine how training background affects the time course of neuromuscular fatigue in response to different resistance exercises. Power athletes (PA, n = 8), strength athletes (SA, n = 8), and nonathletes (NA, n = 7) performed hypertrophic loading (HL, 5 × 10 × 10RM), maximal strength loadings (MSL, 7 × 3 × 3RM) and power loadings (PL, 7 × 6 × 50% of 1 repetition maximum) in back squat. Average power (AP), average velocity (VEL), surface electromyography (sEMG) amplitude (sEMGRMS), and sEMG mean power frequency (sEMGMPF) were measured within all loading sets. During PL, greater decreases in AP occurred from the beginning of SET1 to SET7 and in VEL to both SET4 and SET7 in NA compared with SA (p < 0.01, g > 1.84). During HL, there were various significant group × repetition interactions in AP within and between sets (p < 0.05, ηp2 > 0.307), but post hoc tests did not indicate significant differences between the groups (p > 0.05, g = 0.01-0.93). During MSL and HL, significant within-set and between-set decreases occurred in AP (p < 0.001, ηp2 > 0.701) and VEL (p < 0.001, ηp2 > 0.748) concurrently with increases in sEMGRMS (p < 0.01, ηp2 > 0.323) and decreases in sEMGMPF (p < 0.01, ηp2 > 0.242) in all groups. In conclusion, SA showed fatigue resistance by maintaining higher AP and VEL throughout PL. During HL, PA tended to have the greatest initial fatigue response in AP, but between-group comparisons were nonsignificant despite large effect sizes (g > 0.8). The differences in the progression of neuromuscular fatigue may be related to differing neural activation strategies between the groups, but further research confirmation is required.
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Affiliation(s)
- Johanna Kotikangas
- Biology of Physical Activity, Faculty of Sport and Health Sciences, University of Jyväskylä, Jyväskylä, Finland
- NeuroMuscular Research Center, Jyväskylä, Finland; and
| | - Simon Walker
- Biology of Physical Activity, Faculty of Sport and Health Sciences, University of Jyväskylä, Jyväskylä, Finland
- NeuroMuscular Research Center, Jyväskylä, Finland; and
| | - Heikki Peltonen
- Biology of Physical Activity, Faculty of Sport and Health Sciences, University of Jyväskylä, Jyväskylä, Finland
- NeuroMuscular Research Center, Jyväskylä, Finland; and
- Sport Business, School of Business, Jamk University of Applied Science, Jyväskylä, Finland
| | - Keijo Häkkinen
- Biology of Physical Activity, Faculty of Sport and Health Sciences, University of Jyväskylä, Jyväskylä, Finland
- NeuroMuscular Research Center, Jyväskylä, Finland; and
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Hu H, Wang J, Ouyang L, Luo L, Niu W. The impact of positive-pressure breathing apparatus on muscle fatigue of volunteer firefighter. PLoS One 2024; 19:e0305599. [PMID: 38913654 PMCID: PMC11195949 DOI: 10.1371/journal.pone.0305599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Accepted: 06/03/2024] [Indexed: 06/26/2024] Open
Abstract
Muscle fatigue is one of the leading causes that contributes tremendously to injuries among volunteer firefighters in the workplace. The purpose of this study was to investigate the impact of positive-pressure breathing apparatus on muscle fatigue in the shoulder, back, and legs of volunteer firefighters. A total of 60 volunteer firefighters were recruited to perform a running task on a motorized treadmill in a controlled laboratory environment. Surface electromyography and rating of perceived exertion scores were collected from all participants every 60 seconds during the running task. Results show that the median frequency values for all measured muscle groups were significantly lower, and the rating of perceived exertion score was significantly higher after running with the positive-pressure breathing apparatus. Meanwhile, there were no significant differences in the median frequency values for the upper trapezius, erector spinae, and biceps femoris between the initial and final periods of running task without load. However, the median frequency values with load for gastrocnemius, rectus femoris, and tibialis anterior exhibited a greater downward trend compared to those without load. Additionally, using a breathing apparatus can cause asymmetric muscle fatigue in bilateral upper trapezius, erector spinae, gastrocnemius, and tibialis anterior muscles. The decreased performance due to muscle fatigue increases the risk of accidents, thereby posing a threat to the safety of volunteer firefighters. This study offers valuable insights into the effects of positive-pressure breathing apparatus on muscle fatigue among volunteer firefighters. These results may serve as a reference for developing improved fatigue management strategies and optimizing the design features of breathing apparatus.
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Affiliation(s)
- Huimin Hu
- Ergonomics Laboratory, China National Institute of Standardization, Beijing, China
- SAMR Key Laboratory of Human Factors and Ergonomics, Beijing, China
| | - Jie Wang
- School of Management Engineering, Capital University of Economics and Business, Beijing, China
| | | | - Ling Luo
- Ergonomics Laboratory, China National Institute of Standardization, Beijing, China
- SAMR Key Laboratory of Human Factors and Ergonomics, Beijing, China
| | - Wenlei Niu
- Ergonomics Laboratory, China National Institute of Standardization, Beijing, China
- SAMR Key Laboratory of Human Factors and Ergonomics, Beijing, China
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Sánchez-Valdepeñas J, Cornejo-Daza PJ, Rodiles-Guerrero L, Páez-Maldonado JA, Sánchez-Moreno M, Bachero-Mena B, Saez de Villarreal E, Pareja-Blanco F. Acute Responses to Different Velocity Loss Thresholds during Squat Exercise with Blood-Flow Restriction in Strength-Trained Men. Sports (Basel) 2024; 12:171. [PMID: 38921865 PMCID: PMC11209533 DOI: 10.3390/sports12060171] [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: 05/22/2024] [Revised: 06/14/2024] [Accepted: 06/17/2024] [Indexed: 06/27/2024] Open
Abstract
(1) Background: The aim of this paper is to analyze the acute effects of different velocity loss (VL) thresholds during a full squat (SQ) with blood-flow restriction (BFR) on strength performance, neuromuscular activity, metabolic response, and muscle contractile properties. (2) Methods: Twenty strength-trained men performed four protocols that differed in the VL achieved within the set (BFR0: 0% VL; BFR10: 10% VL; BFR20: 20% VL; and BFR40: 40% VL). The relative intensity (60% 1RM), recovery between sets (2 min), number of sets (3), and level of BFR (50% of arterial occlusion pressure) were matched between protocols. Tensiomyography (TMG), blood lactate, countermovement jump (CMJ), maximal voluntary isometric SQ contraction (MVIC), and performance with the absolute load required to achieve 1 m·s-1 at baseline measurements in SQ were assessed before and after the protocols. (3) Results: BFR40 resulted in higher EMG alterations during and after exercise than the other protocols (p < 0.05). BFR40 also induced greater impairments in TMG-derived variables and BFR10 decreased contraction time. Higher blood lactate concentrations were found as the VL within the set increased. BFR0 and BFR10 showed significantly increased median frequencies in post-exercise MVIC. (4) Conclusions: High VL thresholds (BFR40) accentuated metabolic and neuromuscular stress, and produced increased alterations in muscles' mechanical properties. Low VL could potentiate post-exercise neuromuscular activity and muscle contractile properties.
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Affiliation(s)
- Juan Sánchez-Valdepeñas
- Science Based Training Research Group, Department of Sports and Computer Sciences, Universidad Pablo de Olavide, 41013 Seville, Spain; (P.J.C.-D.); (L.R.-G.); (J.A.P.-M.); (M.S.-M.); (B.B.-M.); (F.P.-B.)
- Faculty of Sport Sciences, Department of Sports and Computer Sciences, Universidad Pablo de Olavide, 41013 Seville, Spain;
| | - Pedro J. Cornejo-Daza
- Science Based Training Research Group, Department of Sports and Computer Sciences, Universidad Pablo de Olavide, 41013 Seville, Spain; (P.J.C.-D.); (L.R.-G.); (J.A.P.-M.); (M.S.-M.); (B.B.-M.); (F.P.-B.)
- Faculty of Sport Sciences, Department of Sports and Computer Sciences, Universidad Pablo de Olavide, 41013 Seville, Spain;
- Department of Human Movement and Sport Performance, University of Seville, 41013 Seville, Spain
| | - Luis Rodiles-Guerrero
- Science Based Training Research Group, Department of Sports and Computer Sciences, Universidad Pablo de Olavide, 41013 Seville, Spain; (P.J.C.-D.); (L.R.-G.); (J.A.P.-M.); (M.S.-M.); (B.B.-M.); (F.P.-B.)
- Department of Human Movement and Sport Performance, University of Seville, 41013 Seville, Spain
| | - Jose A. Páez-Maldonado
- Science Based Training Research Group, Department of Sports and Computer Sciences, Universidad Pablo de Olavide, 41013 Seville, Spain; (P.J.C.-D.); (L.R.-G.); (J.A.P.-M.); (M.S.-M.); (B.B.-M.); (F.P.-B.)
- Centre Attached to the University of Seville, University of Osuna, 41640 Osuna, Spain
| | - Miguel Sánchez-Moreno
- Science Based Training Research Group, Department of Sports and Computer Sciences, Universidad Pablo de Olavide, 41013 Seville, Spain; (P.J.C.-D.); (L.R.-G.); (J.A.P.-M.); (M.S.-M.); (B.B.-M.); (F.P.-B.)
- Department of Physical Education and Sports, University of Seville, 41013 Seville, Spain
| | - Beatriz Bachero-Mena
- Science Based Training Research Group, Department of Sports and Computer Sciences, Universidad Pablo de Olavide, 41013 Seville, Spain; (P.J.C.-D.); (L.R.-G.); (J.A.P.-M.); (M.S.-M.); (B.B.-M.); (F.P.-B.)
- Department of Human Movement and Sport Performance, University of Seville, 41013 Seville, Spain
| | - Eduardo Saez de Villarreal
- Faculty of Sport Sciences, Department of Sports and Computer Sciences, Universidad Pablo de Olavide, 41013 Seville, Spain;
| | - Fernando Pareja-Blanco
- Science Based Training Research Group, Department of Sports and Computer Sciences, Universidad Pablo de Olavide, 41013 Seville, Spain; (P.J.C.-D.); (L.R.-G.); (J.A.P.-M.); (M.S.-M.); (B.B.-M.); (F.P.-B.)
- Faculty of Sport Sciences, Department of Sports and Computer Sciences, Universidad Pablo de Olavide, 41013 Seville, Spain;
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Jain D, Graci V, Beam ME, Master CL, Prosser LA, McDonald CC, Arbogast KB. Impaired Neuromotor Control During Gait in Concussed Adolescents-A Frequency Analysis. J Appl Biomech 2024; 40:138-146. [PMID: 38154023 DOI: 10.1123/jab.2023-0126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 08/27/2023] [Accepted: 11/06/2023] [Indexed: 12/30/2023]
Abstract
Disruptions in gait function are common after concussion in adolescents; however, the neuromotor control deficits driving these gait disruptions are not well known. Fifteen concussed (age mean [SD]): 17.4 [0.6], 13 females, days since injury: 26.3 [9.9]) and 17 uninjured (age: 18.0 [0.7], 10 females) adolescents completed 3 trials each of single-task gait and dual-task gait (DT). During DT, participants simultaneously walked while completing a serial subtraction task. Gait metrics and variability in instantaneous mean frequency in lower extremity muscles were captured by inertial sensors and surface electromyography, respectively. A 2-way analysis of covariance was used to compare gait metrics across groups and conditions. Functional principal components analysis was used to identify regions of variability in instantaneous mean frequency curves. Functional principal component scores were compared across groups using a Welch statistic. Both groups displayed worse performance on gait metrics during DT condition compared to single-task, with no differences between groups (P < .001). Concussed adolescents displayed significantly greater instantaneous mean frequency, indicated by functional principal component 1, in the tibialis anterior, biceps femoris, and semitendinosus (P < .05) during single-task and DT compared with uninjured adolescents. Our observations suggest that concussed adolescents display inefficient motor unit recruitment lasting longer than 2 weeks following injury, regardless of the addition of a secondary task.
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Affiliation(s)
- Divya Jain
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA
- Center for Injury Research and Prevention, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Valentina Graci
- Center for Injury Research and Prevention, Children's Hospital of Philadelphia, Philadelphia, PA, USA
- School of Biomedical Engineering, Science and Health Systems, Drexel University, Philadelphia, PA, USA
| | - Megan E Beam
- Department of Physical Therapy, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Christina L Master
- Center for Injury Research and Prevention, Children's Hospital of Philadelphia, Philadelphia, PA, USA
- Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Sports Medicine and Performance Center, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Laura A Prosser
- Center for Injury Research and Prevention, Children's Hospital of Philadelphia, Philadelphia, PA, USA
- Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Division of Rehabilitation Medicine, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Catherine C McDonald
- Center for Injury Research and Prevention, Children's Hospital of Philadelphia, Philadelphia, PA, USA
- Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- School of Nursing, University of Pennsylvania, Philadelphia, PA, USA
| | - Kristy B Arbogast
- Center for Injury Research and Prevention, Children's Hospital of Philadelphia, Philadelphia, PA, USA
- Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
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Ritzmann R, Strütt S, Torreno I, Riesterer J, Centner C, Suarez-Arrones L. Neuromuscular characteristics of agonists and antagonists during maximal eccentric knee flexion in soccer players with a history of hamstring muscle injuries. PLoS One 2022; 17:e0277949. [PMID: 36455059 PMCID: PMC9714924 DOI: 10.1371/journal.pone.0277949] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Accepted: 11/07/2022] [Indexed: 12/03/2022] Open
Abstract
BACKGROUND Muscle strain injuries (MSIs) in the hamstrings are among the most prevalent injuries in elite soccer. We aimed to examine the relation between biomechanical maladaptation in eccentric strength and neuromuscular factors separated by their time and frequency domains. METHODS 20 elite soccer players with a previous history of unilateral MSI in the M. biceps femoris (BF) long head and 20 without MSI participated. Knee flexion torques, rate of torque development (RTD) and electromyographic signals (EMG) of the BF, the M. semitendinosus (SMT) and knee extensors were obtained during unilateral maximal eccentric knee flexions performed at slow (30°/s) and fast (120°/s) angular speeds. Root mean squares and mean power frequency (MF) was calculated. RESULTS In the group with a history of MSI, reduced maximal eccentric flexion torque (slow eccentrics -8±11, p<0.05; fast eccentrics -18±13 N*m, p<0.05) and RTD (-33±28 N*m/s, p<0.05; -95±47 N*m/s, p<0.05) concomitantly occurred with diminished agonistic myoelectrical activities (-4±5% of MVC, p<0.05; -10±7% of MVC, p<0.05) and MFs (-24±13 Hz, p<0.05; -24±18 Hz, p<0.05) in the BF. Simultaneously, antagonistic myoelectric activity was elevated (+4±3% of MVC, p<0.05; +3±3% of MVC, p<0.05) in MSI affected legs as compared to unaffected legs for both eccentric contractions. Deficits in myoelectrical activity (r2 = 0.715, p<0.05; r2 = 0.601, p<0.05) and MF (r2 = 0.484, p<0.05; r2 = 0.622, p<0.05) correlated with deficits in maximal torque in the affected leg in the MSI group. Analysis of SMT demonstrated no significant differences. CONCLUSION Positive relationships between neuromuscular deficits and the reduced eccentric strength profile underpin neuronal inhibition after MSI. This persistent involvement of dysfunctional synergist and antagonist neural hamstring function in strength weakness is of clinical relevance in sports medicine for prevention and rehabilitation.
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Affiliation(s)
- Ramona Ritzmann
- Department of Sports and Sport Science, University of Freiburg, Freiburg, Germany
- * E-mail:
| | - Sarah Strütt
- Praxisklinik Rennbahn AG, Muttenz, Switzerland
- FC Basel, Basel, Switzerland
| | | | | | | | - Luis Suarez-Arrones
- FC Lugano, Lugano, Switzerland
- Department of Sports and Computer Science, Section of Physical Education and Sports, Universidad Pablo de Olavide, Seville, Spain
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9
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Zhou B, Chen B, Shi H, Xue L, Ao Y, Ding L. SEMG-based fighter pilot muscle fatigue analysis and operation performance research. MEDICINE IN NOVEL TECHNOLOGY AND DEVICES 2022. [DOI: 10.1016/j.medntd.2022.100189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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10
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Pedrosa GF, Machado SC, Diniz RCR, de Lacerda LT, Martins-Costa HC, de Andrade AGP, Bemben M, Chagas MH, Lima FV. The Effects of Altering the Concentric/Eccentric Phase Times on EMG Response, Lactate Accumulation and Work Completed When Training to Failure. J Hum Kinet 2020; 73:33-44. [PMID: 32774535 PMCID: PMC7386151 DOI: 10.2478/hukin-2019-0132] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
This study compared the electromyographic response, the blood lactate concentration (BLC), and the maximum number of repetitions (MNR) between protocols of different concentric/eccentric duration taken to muscle failure. This comparison may help to understand how different concentric/eccentric duration may influence performance and the central and metabolic responses in trained men. Seventeen strength-trained men performed two protocols in a counterbalanced design. Three sets of the Smith bench press exercise were performed to failure at 60% of the one-repetition maximum (1RM) using each protocol (4-s concentric/2-s eccentric [4 s: 2 s]; and 2-s concentric/4-s eccentric [2 s: 4 s]). The normalized root mean square (EMGRMS) and the mean frequency (EMGMF) of the electromyographic signals for the pectoralis major and the triceps brachii were compared in the first, middle, and last repetitions. The BLC was assessed at rest, during and after the test sessions. To compare the EMG and BLC, a 3-way ANOVA with repeated measures with a post hoc Tukey's test was used. To compare the MNR performed across the sets, an ANOVA-type rank test with the Dunn's post hoc test was used. The ANOVA indicated a greater EMGRMS for Protocol 4 s: 2 s in the pectoralis major and a lower EMGMF for Protocol 4 s: 2 s in the triceps brachii at the middle and last repetitions. Both protocols increased the EMGRMS and decreased the EMGMF across repetitions. Despite the results show different levels of activation and neuromuscular fatigue between protocols, the BLC and the MNR were similar.
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Affiliation(s)
- Gustavo Ferreira Pedrosa
- Weight Training Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy of the Federal University of Minas Gerais, Belo Horizonte, Brazil
- Centro de Instrução e Adaptação da Aeronáutica, Lagoa Santa, Brazil
| | - Sandra Carvalho Machado
- Weight Training Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy of the Federal University of Minas Gerais, Belo Horizonte, Brazil
| | - Rodrigo César Ribeiro Diniz
- Weight Training Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy of the Federal University of Minas Gerais, Belo Horizonte, Brazil
| | - Lucas Túlio de Lacerda
- Weight Training Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy of the Federal University of Minas Gerais, Belo Horizonte, Brazil
- Department of Physical Education and Sports, Technological Education Federal Center of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
- Laboratory of Movement Analysis and Human Performance, Department of Physical Education, Pontifical Catholic University of Minas Gerais, Belo Horizonte, Brazil
| | - Hugo Cesar Martins-Costa
- Weight Training Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy of the Federal University of Minas Gerais, Belo Horizonte, Brazil
- Laboratory of Movement Analysis and Human Performance, Department of Physical Education, Pontifical Catholic University of Minas Gerais, Belo Horizonte, Brazil
| | - André Gustavo Pereira de Andrade
- Biomechanical Laboratory of Physical Education, Physiotherapy and Occupational Therapy of the Federal University of Minas Gerais, Belo Horizonte, Brazil
| | - Michael Bemben
- Department of Health and Exercise Science. University of Oklahoma, Norman, United States
| | - Mauro Heleno Chagas
- Weight Training Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy of the Federal University of Minas Gerais, Belo Horizonte, Brazil
| | - Fernando Vitor Lima
- Weight Training Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy of the Federal University of Minas Gerais, Belo Horizonte, Brazil
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11
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Viruega H, Gaillard I, Briatte L, Gaviria M. Inter-Day Reliability and Changes of Surface Electromyography on Two Postural Muscles Throughout 12 Weeks of Hippotherapy on Patients with Cerebral Palsy: A Pilot Study. Brain Sci 2020; 10:brainsci10050281. [PMID: 32384678 PMCID: PMC7288184 DOI: 10.3390/brainsci10050281] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 04/22/2020] [Accepted: 04/30/2020] [Indexed: 11/16/2022] Open
Abstract
Cerebral palsy (CP) is an umbrella term covering a group of permanent developmental disorders of movement and posture characterized by highly variable clinical features. The aim of this study was to assess the short-term and mid-term effects of neurorehabilitation via hippotherapy on the contractile properties of two key postural muscles during functional sitting in such patients. Thirty-minute hippotherapy sessions were conducted biweekly for 12 weeks in 18 patients (18.1 ± 5.7 years old). Surface electromyography (EMG) was implemented bilaterally in rectus abdominis and adductor magnus. We quantitatively analyzed the amplitude of EMG signals in the time domain and its spectral characteristics in the frequency domain. EMGs were recorded at the beginning and end of each session on day one and at week six and week twelve. Statistical analysis revealed a substantial inter-day reliability of the EMG signals for both muscles, validating the methodological approach. To a lesser extent, while beyond the scope of the current study, quantitative changes suggested a more selective recruitment/contractile properties’ shift of the examined muscles. Exploring postural control during functional activities would contribute to understanding the relationship between structural impairment, activity performance and patient capabilities, allowing the design of neurorehabilitation programs aimed at improving postural and functional skills according to each individual’s needs. The present study provides basic quantitative data supporting the body of scientific evidence making hippotherapy an approach of choice for CP neurorehabilitation.
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Ma S, Chen C, Lv B, Sheng X, Zhu X. Estimation of Motor Unit Global Firing Rate by Maximum Power Amplitude. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2020; 2019:6607-6610. [PMID: 31947356 DOI: 10.1109/embc.2019.8857676] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Motor unit (MU) global firing rate is widely applied in physiological and clinical investigation. Currently it still remains difficult to measure the MU global firing rate from sEMG. In this study, we propose a new feature of maximum power amplitude (MPA) from sEMG power spectrum. Based on an analysis of mathematical model and simulated signals, MPA was demonstrated to be highly correlated with the MU global firing rate. The performance of MPA was comparable with features based on sEMG amplitude in the time domain. Moreover, the simulation results showed that the square of MPA changed accordingly with the output force, indicating potential application estimating force using MPA2.
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Stålberg E, van Dijk H, Falck B, Kimura J, Neuwirth C, Pitt M, Podnar S, Rubin DI, Rutkove S, Sanders DB, Sonoo M, Tankisi H, Zwarts M. Standards for quantification of EMG and neurography. Clin Neurophysiol 2019; 130:1688-1729. [DOI: 10.1016/j.clinph.2019.05.008] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 05/07/2019] [Accepted: 05/09/2019] [Indexed: 12/11/2022]
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14
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Lacerda LT, Costa CG, Lima FV, Martins-Costa HC, Diniz RC, Andrade AG, Peixoto GH, Bemben MG, Chagas MH. Longer Concentric Action Increases Muscle Activation and Neuromuscular Fatigue Responses in Protocols Equalized by Repetition Duration. J Strength Cond Res 2019; 33:1629-1639. [DOI: 10.1519/jsc.0000000000002148] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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15
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de Castro F, Alves G, Oliveira L, Tourinho Filho H, Puggina E. Strength training with intermittent blood flow restriction improved strength without changes in neural aspects on quadriceps muscle. Sci Sports 2019. [DOI: 10.1016/j.scispo.2018.10.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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16
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Dideriksen JL, Farina D. Amplitude cancellation influences the association between frequency components in the neural drive to muscle and the rectified EMG signal. PLoS Comput Biol 2019; 15:e1006985. [PMID: 31050667 PMCID: PMC6519845 DOI: 10.1371/journal.pcbi.1006985] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Revised: 05/15/2019] [Accepted: 03/27/2019] [Indexed: 12/11/2022] Open
Abstract
The rectified surface EMG signal is commonly used as an estimator of the neural drive to muscles and therefore to infer sources of synaptic input to motor neurons. Loss of EMG amplitude due to the overlap of motor unit action potentials (amplitude cancellation), however, may distort the spectrum of the rectified EMG and thereby its correlation with the neural drive. In this study, we investigated the impact of amplitude cancelation on this correlation using analytical derivations and a computational model of motor neuron activity, force, and the EMG signal. First, we demonstrated analytically that an ideal rectified EMG signal without amplitude cancellation (EMGnc) is superior to the actual rectified EMG signal as estimator of the neural drive to muscle. This observation was confirmed by the simulations, as the average coefficient of determination (r2) between the neural drive in the 1–30 Hz band and EMGnc (0.59±0.08) was matched by the correlation between the rectified EMG and the neural drive only when the level of amplitude cancellation was low (<40%) at low contraction levels (<5% of maximum voluntary contraction force; MVC). This correlation, however, decreased linearly with amplitude cancellation (r = -0.83) to values of r2 <0.2 at amplitude cancellation levels >60% (contraction levels >15% MVC). Moreover, the simulations showed that a stronger (i.e. more variable) neural drive implied a stronger correlation between the rectified EMG and the neural drive and that amplitude cancellation distorted this correlation mainly for low-frequency components (<5 Hz) of the neural drive. In conclusion, the results indicate that amplitude cancellation distorts the spectrum of the rectified EMG signal. This implies that valid use of the rectified EMG as an estimator of the neural drive requires low contraction levels and/or strong common synaptic input to the motor neurons. The rectified surface EMG signal is commonly used to analyze the neural activation of muscles. However, since this signal is most often exposed to so-called amplitude cancellation (loss of EMG amplitude due to overlap of positive and negative phases of different motor unit action potentials), the frequency content of the rectified EMG may not fully reflect that of the neural drive to the muscle. In this study we prove this notion analytically and demonstrate, using simulations, that the rectified EMG signal accurately reflects the neural drive to the muscle only in a limited set of conditions. Specifically, these conditions include low contraction levels and/or high variability of the neural drive. In other conditions, the rectified EMG signal from a muscle is a poor predictor of its neural input. This finding has potentially large implications for the way neural drive to muscles and neural connectivity (e.g. across muscles or between the brain and a muscle) should be analyzed.
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Affiliation(s)
| | - Dario Farina
- Department of Bioengineering, Imperial College London, London, United Kingdom
- * E-mail:
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17
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Lubkowska A, Radecka A, Bryczkowska I, Rotter I, Laszczyńska M, Karakiewicz B. Changes in the bioelectric activity of the trapezius muscle following the thermal effect of red light and infrared radiation. J Back Musculoskelet Rehabil 2018. [PMID: 29526838 DOI: 10.3233/bmr-169745] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND The therapeutic effects of visible light and infrared is especially often used in physiotherapy. OBJECTIVE The purpose of this study was to determine the effect of exposure to radiation on the motor units activity. METHODS The study included 29 volunteers of whom the spontaneous and voluntary bioelectric activity of the trapezius muscle was evaluated using surface electromyography (value of average amplitude and frequency), before and immediately after a 15-minute irradiation. Additionally, the range of motion of the cervical spine and trigger points pain sensitivity to the pressure were assessed. RESULTS No statistically significant changes in the pain sensitivity threshold and the range of motion after the irradiation was applied. On the other hand, a 15-minute exposure to radiation induced an increase in the value of average amplitude of rest-related as well as exercise-related potentials and an increase in the average value of frequency of the right side biopotentials at rest and of both sides for active elevation. CONCLUSIONS Infrared radiation and visible red light have a stimulating effect on the muscle ability to develop active contraction. It is proposed that the observed changes are associated with the thermal effect of radiation as well as with the so-called extra-visual effects.
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Affiliation(s)
- Anna Lubkowska
- Department of Functional Diagnostics and Physical Medicine, Faculty of Health Sciences, Pomeranian Medical University in Szczecin, 71-210 Szczecin, Poland
| | - Aleksandra Radecka
- Department of Functional Diagnostics and Physical Medicine, Faculty of Health Sciences, Pomeranian Medical University in Szczecin, 71-210 Szczecin, Poland
| | - Iwona Bryczkowska
- Department of Functional Diagnostics and Physical Medicine, Faculty of Health Sciences, Pomeranian Medical University in Szczecin, 71-210 Szczecin, Poland
| | - Iwona Rotter
- Independent Laboratory of Medical Rehabilitation, Pomeranian Medical University in Szczecin, 71-210 Szczecin, Poland
| | - Maria Laszczyńska
- Department of Histology and Developmental Biology, Pomeranian Medical University, 71-210 Szczecin, Poland
| | - Beata Karakiewicz
- Department of Public Health, Faculty of Health Sciences, Pomeranian Medical University, 71-210 Szczecin, Poland
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18
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Klimesch W. The frequency architecture of brain and brain body oscillations: an analysis. Eur J Neurosci 2018; 48:2431-2453. [PMID: 30281858 PMCID: PMC6668003 DOI: 10.1111/ejn.14192] [Citation(s) in RCA: 96] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2017] [Revised: 08/19/2018] [Accepted: 09/13/2018] [Indexed: 01/04/2023]
Abstract
Research on brain oscillations has brought up a picture of coupled oscillators. Some of the most important questions that will be analyzed are, how many frequencies are there, what are the coupling principles, what their functional meaning is, and whether body oscillations follow similar coupling principles. It is argued that physiologically, two basic coupling principles govern brain as well as body oscillations: (i) amplitude (envelope) modulation between any frequencies m and n, where the phase of the slower frequency m modulates the envelope of the faster frequency n, and (ii) phase coupling between m and n, where the frequency of n is a harmonic multiple of m. An analysis of the center frequency of traditional frequency bands and their coupling principles suggest a binary hierarchy of frequencies. This principle leads to the foundation of the binary hierarchy brain body oscillation theory. Its central hypotheses are that the frequencies of body oscillations can be predicted from brain oscillations and that brain and body oscillations are aligned to each other. The empirical evaluation of the predicted frequencies for body oscillations is discussed on the basis of findings for heart rate, heart rate variability, breathing frequencies, fluctuations in the BOLD signal, and other body oscillations. The conclusion is that brain and many body oscillations can be described by a single system, where the cross talk - reflecting communication - within and between brain and body oscillations is governed by m : n phase to envelope and phase to phase coupling.
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Affiliation(s)
- Wolfgang Klimesch
- Centre of Cognitive NeuroscienceUniversity of SalzburgSalzburgAustria
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Jian C, Wei M, Luo J, Lin J, Zeng W, Huang W, Song R. Multiparameter Electromyography Analysis of the Masticatory Muscle Activities in Patients with Brainstem Stroke at Different Head Positions. Front Neurol 2017; 8:221. [PMID: 28611725 PMCID: PMC5447052 DOI: 10.3389/fneur.2017.00221] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Accepted: 05/08/2017] [Indexed: 12/02/2022] Open
Abstract
The performance of the masticatory muscle is frequently affected and presents high heterogeneity poststroke. Surface electromyography (EMG) is widely used to quantify muscle movement patterns. However, only a few studies applied EMG analysis on the research of masticatory muscle activities poststroke, and most of which used single parameter—root mean squares (RMS). The aim of this study was to fully investigate the performance of masticatory muscle at different head positions in healthy subjects and brainstem stroke patients with multiparameter EMG analysis. In this study, 15 healthy subjects and six brainstem stroke patients were recruited to conduct maximum voluntary clenching at five different head positions: upright position, left rotation, right rotation, dorsal flexion, and ventral flexion. The EMG signals of bilateral temporalis anterior and masseter muscles were recorded, and parameters including RMS, median frequency, and fuzzy approximate entropy of the EMG signals were calculated. Two-way analysis of variance (ANOVA) with repeated measures and Bonferroni post hoc test were used to evaluate the effects of muscle and head position on EMG parameters in the healthy group, and the non-parametric Wilcoxon signed rank test was conducted in the patient group. The Welch–Satterthwaite t-test was used to compare the between-subject difference. We found a significant effect of subject and muscles but no significant effect of head positions, and the masticatory muscles of patients after brainstem stroke performed significantly different from healthy subjects. Multiparameter EMG analysis might be an informative tool to investigate the neural activity related movement patterns of the deficient masticatory muscles poststroke.
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Affiliation(s)
- Chuyao Jian
- Key Laboratory of Sensing Technology and Biomedical Instrument of Guang Dong Province, Guangdong Provincial Engineering and Technology Center of Advanced and Portable Medical Devices, Sun Yat-sen University, Guangzhou, China
| | - Miaoluan Wei
- Key Laboratory of Sensing Technology and Biomedical Instrument of Guang Dong Province, Guangdong Provincial Engineering and Technology Center of Advanced and Portable Medical Devices, Sun Yat-sen University, Guangzhou, China
| | - Jie Luo
- Key Laboratory of Sensing Technology and Biomedical Instrument of Guang Dong Province, Guangdong Provincial Engineering and Technology Center of Advanced and Portable Medical Devices, Sun Yat-sen University, Guangzhou, China
| | - Jiayin Lin
- Key Laboratory of Sensing Technology and Biomedical Instrument of Guang Dong Province, Guangdong Provincial Engineering and Technology Center of Advanced and Portable Medical Devices, Sun Yat-sen University, Guangzhou, China
| | - Wen Zeng
- Key Laboratory of Sensing Technology and Biomedical Instrument of Guang Dong Province, Guangdong Provincial Engineering and Technology Center of Advanced and Portable Medical Devices, Sun Yat-sen University, Guangzhou, China
| | - Weitian Huang
- Department of Stroke Rehabilitation, Guangdong Work Injury Rehabilitation Center, Guangzhou, China
| | - Rong Song
- Key Laboratory of Sensing Technology and Biomedical Instrument of Guang Dong Province, Guangdong Provincial Engineering and Technology Center of Advanced and Portable Medical Devices, Sun Yat-sen University, Guangzhou, China
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20
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Community Gardens as Health Promoters: Effects on Mental and Physical Stress Levels in Adults with and without Mental Disabilities. SUSTAINABILITY 2017. [DOI: 10.3390/su9010063] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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21
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Askary-Ashtiani A, Ghanjal A, Motaqi M, Meftahi GH, Hatef B, Niknam H. The Isokinetic and Electromyographic Assessment of Knee Muscles Strength in the Short- and Long-Term Type 2 Diabetes. Asian J Sports Med 2016; 7:e37008. [PMID: 28144413 PMCID: PMC5259685 DOI: 10.5812/asjsm.37008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Revised: 05/09/2016] [Accepted: 05/17/2016] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND Type 2 diabetes (T2DM) patients are subject to muscle weakness. OBJECTIVES The aim of the study was an assessment of electromyographic (EMG) activity of knee muscles during isometric maximal voluntary contraction in the different disease durations of T2DM. METHODS Eighteen patients with less than 10 years and twelve patients with more than 10 years of T2DM were compared with nineteen matched healthy control subjects. EMG of flexor and extensor muscles of knee concurrently with isometric maximal peak torque of knee flexion and extension at 75 degrees of knee flexion were recorded in three groups. RESULTS Isometric maximal peak torque of extension and root mean squared (RMS) of vastus lateralis and medial hamstring in the healthy control was significantly higher than both patient groups. Whenever the maximal isometric peak flexion torque was not significantly different between groups, the mean power frequency (MPF) of flexor muscles especially medial hamstrings were higher in the short-term T2DM than healthy control groups. The two factors, gender and age, had significant effect on maximal peak torque and RMS of knee muscles. CONCLUSIONS EMG could show the effect of T2DM, gender and age on knee muscles activity. It seems that the medial hamstring was the most sensitive muscle of knee compartment to show the effect of T2DM and difference of short and long-term T2DM in EMG study.
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Affiliation(s)
| | - Ali Ghanjal
- Health Management Research Centre, Department of Physical Medicine and Rehabilitation, Baqiyatallah University, Tehran, Iran
| | - Monireh Motaqi
- Departement of Basic Science, Rehabilitation Faculty, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | | | - Boshra Hatef
- Neuroscience Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran
| | - Hoda Niknam
- Department of Physical Therapy, Tarbiat Modares University, Tehran, Iran
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Beck TW, Ye X, Wages NP, Carr JC. Cross spectral analysis of the force and surface electromyographic signals for examining steadiness following different exercise interventions. Biomed Phys Eng Express 2016. [DOI: 10.1088/2057-1976/2/4/045013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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23
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Grossi S, Grassi F, Galleani L, Bianchi F, Sibona Masi A, Conte MR. Atrial Conduction Velocity Correlates with Frequency Content of Bipolar Signal. PACING AND CLINICAL ELECTROPHYSIOLOGY: PACE 2016; 39:814-21. [PMID: 27196672 DOI: 10.1111/pace.12884] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Revised: 03/31/2016] [Accepted: 04/30/2016] [Indexed: 01/22/2023]
Abstract
BACKGROUND Anisotropy in conduction velocity (CV) is a key substrate abnormality influencing atrial arrhythmias. In skeletal muscle fibers, CV and frequency content of the surface electromyogram signal are directly related. We hypothesized that in human atria the frequency content of the bipolar signal, recorded on the endocardial surface, is directly related to the local CV. METHODS In 15 patients submitted to ablation of supraventricular arrhythmias, incremental pacing was performed through an octapolar catheter inserted into the coronary sinus (CS), alternatively from both extremities in two different sequences: CS bipole 1-2 as the pacing site and CS bipole 7-8 as the detection site in the first, and vice versa in the second. The pacing cycle length (PCL) was stepwise decreased from 600 ms to 500 ms, 400 ms, 300 ms, until 250 ms. Estimation of the CV was performed as the ratio between the distance traveled by the propagating pulse and the propagation time. The frequency distribution of the signal energy was estimated using the fast Fourier transform, and the characteristic frequency (CF) was estimated as the barycenter of the frequency spectrum. RESULTS A total of 2,496 bipolar signals were analyzed; CV and CF were estimated and compared. The single patient and group data analysis showed a significant direct correlation between CV and CF of the local bipolar signal. CONCLUSIONS Comparing the degree of spectral compression among signals registered in different points of the endocardial cardiac surface in response to decreasing PCL enables to map local differences in CV, a useful arrhythmogenic substrate index.
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Affiliation(s)
- Stefano Grossi
- Cardiology Department, Mauriziano Hospital, Turin, Italy
| | - Francesco Grassi
- Department of Electronics and Telecommunications, Politecnico di Torino, Italy
| | - Lorenzo Galleani
- Department of Electronics and Telecommunications, Politecnico di Torino, Italy
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Use of muscle synergies and wavelet transforms to identify fatigue during squatting. J Electromyogr Kinesiol 2016; 28:158-66. [PMID: 27156237 DOI: 10.1016/j.jelekin.2016.04.008] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Revised: 04/20/2016] [Accepted: 04/21/2016] [Indexed: 11/22/2022] Open
Abstract
The objective of this study was to supplement continuous wavelet transforms with muscle synergies in a fatigue analysis to better describe the combination of decreased firing frequency and altered activation profiles during dynamic muscle contractions. Nine healthy young individuals completed the dynamic tasks before and after they squatted with a standard Olympic bar until complete exhaustion. Electromyography (EMG) profiles were analyzed with a novel concatenated non-negative matrix factorization method that decomposed EMG signals into muscle synergies. Muscle synergy analysis provides the activation pattern of the muscles while continuous wavelet transforms output the temporal frequency content of the EMG signals. Synergy analysis revealed subtle changes in two-legged squatting after fatigue while differences in one-legged squatting were more pronounced and included the shift from a general co-activation of muscles in the pre-fatigue state to a knee extensor dominant weighting post-fatigue. Continuous wavelet transforms showed major frequency content decreases in two-legged squatting after fatigue while very few frequency changes occurred in one-legged squatting. It was observed that the combination of methods is an effective way of describing muscle fatigue and that muscle activation patterns play a very important role in maintaining the overall joint kinetics after fatigue.
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25
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Herda TJ, Siedlik JA, Trevino MA, Cooper MA, Weir JP. Motor unit control strategies of endurance- versus resistance-trained individuals. Muscle Nerve 2015; 52:832-43. [DOI: 10.1002/mus.24597] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2014] [Revised: 01/29/2015] [Accepted: 02/03/2015] [Indexed: 11/05/2022]
Affiliation(s)
- Trent J. Herda
- Neuromechanics Laboratory; Department of Health; Sport; and Exercise Sciences; University of Kansas; 1301 Sunnyside Avenue, Room 101BE Lawrence Kansas 66045 USA
| | - Jacob A. Siedlik
- Neuromechanics Laboratory; Department of Health; Sport; and Exercise Sciences; University of Kansas; 1301 Sunnyside Avenue, Room 101BE Lawrence Kansas 66045 USA
| | - Michael A. Trevino
- Neuromechanics Laboratory; Department of Health; Sport; and Exercise Sciences; University of Kansas; 1301 Sunnyside Avenue, Room 101BE Lawrence Kansas 66045 USA
| | - Michael A. Cooper
- Neuromechanics Laboratory; Department of Health; Sport; and Exercise Sciences; University of Kansas; 1301 Sunnyside Avenue, Room 101BE Lawrence Kansas 66045 USA
| | - Joseph P. Weir
- Neuromechanics Laboratory; Department of Health; Sport; and Exercise Sciences; University of Kansas; 1301 Sunnyside Avenue, Room 101BE Lawrence Kansas 66045 USA
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26
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Jenkins NDM, Housh TJ, Bergstrom HC, Cochrane KC, Hill EC, Smith CM, Johnson GO, Schmidt RJ, Cramer JT. Muscle activation during three sets to failure at 80 vs. 30% 1RM resistance exercise. Eur J Appl Physiol 2015; 115:2335-47. [PMID: 26159316 DOI: 10.1007/s00421-015-3214-9] [Citation(s) in RCA: 82] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Accepted: 06/28/2015] [Indexed: 10/23/2022]
Abstract
PURPOSE The purpose of this study was to investigate electromyographic amplitude (EMG AMP), EMG mean power frequency (MPF), exercise volume (VOL), total work and muscle activation (iEMG), and time under concentric load (TUCL) during, and muscle cross-sectional area (mCSA) before and after 3 sets to failure at 80 vs. 30 % 1RM resistance exercise. METHODS Nine men (mean ± SD, age 21.0 ± 2.4 years, resistance training week(-1) 6.0 ± 3.7 h) and 9 women (age 22.8 ± 3.8 years, resistance training week(-1) 3.4 ± 3.5 h) completed 1RM testing, followed by 2 experimental sessions during which they completed 3 sets to failure of leg extension exercise at 80 or 30 % 1RM. EMG signals were collected to quantify EMG AMP and MPF during the initial, middle, and last repetition of each set. Ultrasound was used to assess mCSA pre- and post-exercise, and VOL, total work, iEMG, and TUCL were calculated. RESULTS EMG AMP remained greater at 80 % than 30 % 1RM across all reps and sets, despite increasing 74 and 147 % across reps at 80 and 30 % 1RM, respectively. EMG MPF decreased across reps at 80 and 30 % 1RM, but decreased more and was lower for the last reps at 30 than 80 % 1RM (71.6 vs. 78.1 % MVIC). mCSA increased more from pre- to post-exercise for 30 % (20.2-24.1 cm(2)) than 80 % 1RM (20.3-22.8 cm(2)). VOL, total work, iEMG and TUCL were greater for 30 % than 80 % 1RM. CONCLUSION Muscle activation was greater at 80 % 1RM. However, differences in volume, metabolic byproduct accumulation, and muscle swelling may help explain the unexpected adaptations in hypertrophy vs. strength observed in previous studies.
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Affiliation(s)
- Nathaniel D M Jenkins
- Department of Nutrition and Health Sciences, Room 211, Ruth Leverton Hall, University of Nebraska-Lincoln, Lincoln, NE, 68583-0806, USA
| | - Terry J Housh
- Department of Nutrition and Health Sciences, Room 211, Ruth Leverton Hall, University of Nebraska-Lincoln, Lincoln, NE, 68583-0806, USA
| | - Haley C Bergstrom
- Department of Kinesiology and Health Promotion, 221 Seaton Building, University of Kentucky, Lexington, KY, 40506-0219, USA
| | - Kristen C Cochrane
- Department of Nutrition and Health Sciences, Room 211, Ruth Leverton Hall, University of Nebraska-Lincoln, Lincoln, NE, 68583-0806, USA
| | - Ethan C Hill
- Department of Nutrition and Health Sciences, Room 211, Ruth Leverton Hall, University of Nebraska-Lincoln, Lincoln, NE, 68583-0806, USA
| | - Cory M Smith
- Department of Nutrition and Health Sciences, Room 211, Ruth Leverton Hall, University of Nebraska-Lincoln, Lincoln, NE, 68583-0806, USA
| | - Glen O Johnson
- Department of Nutrition and Health Sciences, Room 211, Ruth Leverton Hall, University of Nebraska-Lincoln, Lincoln, NE, 68583-0806, USA
| | - Richard J Schmidt
- Department of Nutrition and Health Sciences, Room 211, Ruth Leverton Hall, University of Nebraska-Lincoln, Lincoln, NE, 68583-0806, USA
| | - Joel T Cramer
- Department of Nutrition and Health Sciences, Room 211, Ruth Leverton Hall, University of Nebraska-Lincoln, Lincoln, NE, 68583-0806, USA.
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McManus L, Hu X, Rymer WZ, Lowery MM, Suresh NL. Changes in motor unit behavior following isometric fatigue of the first dorsal interosseous muscle. J Neurophysiol 2015; 113:3186-96. [PMID: 25761952 PMCID: PMC4432683 DOI: 10.1152/jn.00146.2015] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Accepted: 03/06/2015] [Indexed: 11/22/2022] Open
Abstract
The neuromuscular strategies employed to compensate for fatigue-induced muscle force deficits are not clearly understood. This study utilizes surface electromyography (sEMG) together with recordings of a population of individual motor unit action potentials (MUAPs) to investigate potential compensatory alterations in motor unit (MU) behavior immediately following a sustained fatiguing contraction and after a recovery period. EMG activity was recorded during abduction of the first dorsal interosseous in 12 subjects at 20% maximum voluntary contraction (MVC), before and directly after a 30% MVC fatiguing contraction to task failure, with additional 20% MVC contractions following a 10-min rest. The amplitude, duration and mean firing rate (MFR) of MUAPs extracted with a sEMG decomposition system were analyzed, together with sEMG root-mean-square (RMS) amplitude and median frequency (MPF). MUAP duration and amplitude increased immediately postfatigue and were correlated with changes to sEMG MPF and RMS, respectively. After 10 min, MUAP duration and sEMG MPF recovered to prefatigue values but MUAP amplitude and sEMG RMS remained elevated. MU MFR and recruitment thresholds decreased postfatigue and recovered following rest. The increase in MUAP and sEMG amplitude likely reflects recruitment of larger MUs, while recruitment compression is an additional compensatory strategy directly postfatigue. Recovery of MU MFR in parallel with MUAP duration suggests a possible role for metabolically sensitive afferents in MFR depression postfatigue. This study provides insight into fatigue-induced neuromuscular changes by examining the properties of a large population of concurrently recorded single MUs and outlines possible compensatory strategies involving alterations in MU recruitment and MFR.
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Affiliation(s)
- Lara McManus
- University College Dublin, Belfield, Dublin, Ireland;
| | - Xiaogang Hu
- Rehabilitation Institute of Chicago, Chicago, Illinois; and
| | - 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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Beck TW, Ye X, Wages NP. Local muscle endurance is associated with fatigue-based changes in electromyographic spectral properties, but not with conduction velocity. J Electromyogr Kinesiol 2015; 25:451-6. [PMID: 25744086 DOI: 10.1016/j.jelekin.2015.02.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Revised: 02/11/2015] [Accepted: 02/13/2015] [Indexed: 11/17/2022] Open
Abstract
The purpose of this study was to examine the associations amongst muscle fiber action potential conduction velocity (CV), spectral characteristics of the surface electromyographic (EMG) signal, and endurance time during a sustained submaximal isometric muscle action. Eleven men (mean±SD age=23±4yrs) performed a sustained, submaximal isometric muscle action of the dominant forearm flexors at 60% of the maximum voluntary contraction (MVC) until the designated force level could no longer be maintained. Sixteen separate bipolar surface EMG signals were detected from the biceps brachii with a linear electrode array during this contraction. Two channels from this array were used to measure CV, and one of these two channels was used for further EMG signal processing. The channels that provided the highest signal quality were used for the CV measurements and further data analysis. A wavelet analysis was then used to analyze the bipolar EMG signal, and the resulting wavelet spectrum was decomposed with a nonparametric spectral decomposition procedure. The results showed that the time to exhaustion during the sustained contraction was not correlated with the rate of decrease in CV, but it was highly correlated with both the decrease in high-frequency spectral power (r=0.947) and the increase in low-frequency spectral power (r=0.960). These findings are particularly interesting, considering that the decrease in traditional EMG spectral variables (e.g., mean frequency or median frequency) with fatigue is generally attributed to reductions in CV. While this may indeed be true, the present results suggested that other factors (i.e., other than CV) that can affect the shape of the EMG frequency spectrum during fatigue are more important in determining the endurance capabilities of the muscle than is CV.
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Affiliation(s)
- Travis W Beck
- Biophysics Laboratory, University of Oklahoma, Department of Health and Exercise Science, 110 Huston Huffman Center, Norman, OK 73019-6081, United States.
| | - Xin Ye
- Biophysics Laboratory, University of Oklahoma, Department of Health and Exercise Science, 110 Huston Huffman Center, Norman, OK 73019-6081, United States
| | - Nathan P Wages
- Biophysics Laboratory, University of Oklahoma, Department of Health and Exercise Science, 110 Huston Huffman Center, Norman, OK 73019-6081, United States
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29
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Lomax M, Tasker L, Bostanci O. An electromyographic evaluation of dual role breathing and upper body muscles in response to front crawl swimming. Scand J Med Sci Sports 2014; 25:e472-8. [DOI: 10.1111/sms.12354] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/05/2014] [Indexed: 11/29/2022]
Affiliation(s)
- M. Lomax
- Department of Sports and Exercise Science; University of Portsmouth; Hampshire UK
| | - L. Tasker
- School of Sport and Exercise; University of Gloucestershire; Gloucester UK
| | - O. Bostanci
- Department of Physical Education and Sports; University of Ondokuz Mayis; Samsun Turkey
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30
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Mechanomyographic parameter extraction methods: an appraisal for clinical applications. SENSORS 2014; 14:22940-70. [PMID: 25479326 PMCID: PMC4299047 DOI: 10.3390/s141222940] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Revised: 10/28/2014] [Accepted: 11/04/2014] [Indexed: 11/16/2022]
Abstract
The research conducted in the last three decades has collectively demonstrated that the skeletal muscle performance can be alternatively assessed by mechanomyographic signal (MMG) parameters. Indices of muscle performance, not limited to force, power, work, endurance and the related physiological processes underlying muscle activities during contraction have been evaluated in the light of the signal features. As a non-stationary signal that reflects several distinctive patterns of muscle actions, the illustrations obtained from the literature support the reliability of MMG in the analysis of muscles under voluntary and stimulus evoked contractions. An appraisal of the standard practice including the measurement theories of the methods used to extract parameters of the signal is vital to the application of the signal during experimental and clinical practices, especially in areas where electromyograms are contraindicated or have limited application. As we highlight the underpinning technical guidelines and domains where each method is well-suited, the limitations of the methods are also presented to position the state of the art in MMG parameters extraction, thus providing the theoretical framework for improvement on the current practices to widen the opportunity for new insights and discoveries. Since the signal modality has not been widely deployed due partly to the limited information extractable from the signals when compared with other classical techniques used to assess muscle performance, this survey is particularly relevant to the projected future of MMG applications in the realm of musculoskeletal assessments and in the real time detection of muscle activity.
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Lomax M, Tasker L, Bostanci O. Inspiratory Muscle Fatigue Affects Latissimus Dorsi but Not Pectoralis Major Activity During Arms Only Front Crawl Sprinting. J Strength Cond Res 2014; 28:2262-9. [DOI: 10.1519/jsc.0000000000000379] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Doulah ABMSU, Fattah SA, Zhu WP, Ahmad MO. DCT domain feature extraction scheme based on motor unit action potential of EMG signal for neuromuscular disease classification. Healthc Technol Lett 2014; 1:26-31. [PMID: 26609372 DOI: 10.1049/htl.2013.0036] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2013] [Revised: 03/14/2014] [Accepted: 03/17/2014] [Indexed: 11/20/2022] Open
Abstract
A feature extraction scheme based on discrete cosine transform (DCT) of electromyography (EMG) signals is proposed for the classification of normal event and a neuromuscular disease, namely the amyotrophic lateral sclerosis. Instead of employing DCT directly on EMG data, it is employed on the motor unit action potentials (MUAPs) extracted from the EMG signal via a template matching-based decomposition technique. Unlike conventional MUAP-based methods, only one MUAP with maximum dynamic range is selected for DCT-based feature extraction. Magnitude and frequency values of a few high-energy DCT coefficients corresponding to the selected MUAP are used as the desired feature which not only reduces computational burden, but also offers better feature quality with high within-class compactness and between-class separation. For the purpose of classification, the K-nearest neighbourhood classifier is employed. Extensive analysis is performed on clinical EMG database and it is found that the proposed method provides a very satisfactory performance in terms of specificity, sensitivity and overall classification accuracy.
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Affiliation(s)
| | | | - Wei-Ping Zhu
- Department of Electrical and Computer Engineering , Concordia University , Montreal , QC , H3G 1M8 , Canada
| | - M Omair Ahmad
- Department of Electrical and Computer Engineering , Concordia University , Montreal , QC , H3G 1M8 , Canada
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33
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Doulah ABMSU, Fattah SA, Zhu WP, Ahmad MO. Wavelet domain feature extraction scheme based on dominant motor unit action potential of EMG signal for neuromuscular disease classification. IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS 2014; 8:155-164. [PMID: 24759993 DOI: 10.1109/tbcas.2014.2309252] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
In this paper, two schemes for neuromuscular disease classification from electromyography (EMG) signals are proposed based on discrete wavelet transform (DWT) features. In the first scheme, a few high energy DWT coefficients along with the maximum value are extracted in a frame by frame manner from the given EMG data. Instead of considering only such local information obtained from a single frame, we propose to utilize global statistics which is obtained based on information collected from some consecutive frames. In the second scheme, motor unit action potentials (MUAPs) are first extracted from the EMG data via template matching based decomposition technique. It is well known that not all MUAPs obtained via decomposition are capable of uniquely representing a class. Thus, a novel idea of selecting a dominant MUAP, based on energy criterion, is proposed and instead of all MUAPs, only the dominant MUAP is used for the classification. A feature extraction scheme based on some statistical properties of the DWT coefficients of dominant MUAPs is proposed. For the purpose of classification, the K-nearest neighborhood (KNN) classifier is employed. Extensive analysis is performed on clinical EMG database for the classification of neuromuscular diseases and it is found that the proposed methods provide a very satisfactory performance in terms of specificity, sensitivity, and overall classification accuracy.
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Miura T, Sakuraba K. Properties of Force Output and Spectral EMG in Young Patients with Nonspecific Low Back Pain during Isometric Trunk Extension. J Phys Ther Sci 2014; 26:323-9. [PMID: 24707077 PMCID: PMC3975996 DOI: 10.1589/jpts.26.323] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Accepted: 09/22/2013] [Indexed: 12/19/2022] Open
Abstract
[Purpose] To clarify the influence of nonspecific low back pain (NSLBP) on force
fluctuation and the myoelectric data of back muscles during isometric trunk extension at
low to high force levels. [Subjects] Fourteen male subjects with NSLBP and 14 healthy male
control subjects participated in this study. [Methods] All participants extended their
trunk isometrically maintaining 10 levels of target force [2, 5, 10, 15, 20, 30, 50, 70,
80 and 90% of maximal voluntary contraction (MVC) in a random order] for about 4 seconds
with visual feedback. A force transducer and tri-axis force sensor were positioned at the
7th thoracic vertebra to measure force output and the direction of force. Myoelectric
activities of the back muscles (longissimus thoracis, L2 level; multifidus, S1 level) were
recorded by surface electromyography. [Results] Force output of NSLBP subjects fluctuated
more than that of healthy subjects at 30% and 50%MVC. Higher median power frequency in the
multifidus was observed in NSLBP subjects at moderate to high force levels. [Conclusion]
These results show that the properties of force output in NSLBP subjects differ from those
in healthy subjects, suggesting that the assessment of force fluctuation of back muscles
at moderate force levels is a useful index for evaluating and discriminating NSLBP.
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Affiliation(s)
- Tatsuhiro Miura
- Department of Sports Medicine, Graduate School of Medicine, Juntendo University, Japan
| | - Keishoku Sakuraba
- Department of Sports Medicine, Graduate School of Health and Sports Science, Juntendo University, Japan
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35
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Tirosh O, Sangeux M, Wong M, Thomason P, Graham HK. Walking speed effects on the lower limb electromyographic variability of healthy children aged 7–16years. J Electromyogr Kinesiol 2013; 23:1451-9. [DOI: 10.1016/j.jelekin.2013.06.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2012] [Revised: 03/13/2013] [Accepted: 06/08/2013] [Indexed: 10/26/2022] Open
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Hébert-Losier K, Schneiders AG, García JA, Sullivan SJ, Simoneau GG. Influence of knee flexion angle and age on triceps surae muscle fatigue during heel raises. J Strength Cond Res 2013; 26:3134-47. [PMID: 22158096 DOI: 10.1519/jsc.0b013e318243ff0e] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The triceps surae (TS) muscle-tendon unit is 1 of the most commonly injured in elite and recreational athletes, with a high prevalence in middle-aged adults. The performance of maximal numbers of unilateral heel raises is used to assess, train, and rehabilitate TS endurance and conventionally prescribed in 0° knee flexion (KF) for the gastrocnemius and 45° for the soleus (SOL). However, the extent of muscle selectivity conferred through the change in the knee angle is lacking for heel raises performed to volitional fatigue. This study investigated the influence of knee angle on TS muscle fatigue during heel raises and determined whether fatigue differed between middle-aged and younger-aged adults. Forty-eight healthy individuals aged 18-25 and 35-45 years performed maximal numbers of unilateral heel raises in 0° and 45° KF. Median frequencies and linear regression slopes were calculated from the SOL, gastrocnemius medialis (GM), and gastrocnemius lateralis (GL) surface electromyographic signals. Stepwise mixed-effect regressions were used for analysis. The subjects completed an average of 45 and 48 heel raises in 0° and 45° KF, respectively. The results indicated that the 3 muscles fatigued during testing as all median frequencies decreased, and regression slopes were negative. Consistent with muscle physiology and fiber typing, fatigue was greater in the GM and GL than in the SOL (p < 0.001). However, knee angle did not influence TS muscle fatigue parameters (p = 0.814), with similar SOL, GM, and GL fatigue in 0° and 45° KF. These findings are in contrast with the traditionally described clinical use of heel raises in select knee angles for the gastrocnemius and the SOL. Furthermore, no difference in TS fatigue between the 2 age groups was able to be determined, despite the reported higher prevalence of injury in middle-aged individuals.
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Affiliation(s)
- Kim Hébert-Losier
- Center for Physiotherapy Research, School of Physiotherapy, University of Otago, Dunedin, New Zealand
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37
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Boudarham J, Hameau S, Pradon D, Bensmail D, Roche N, Zory R. Changes in electromyographic activity after botulinum toxin injection of the rectus femoris in patients with hemiparesis walking with a stiff-knee gait. J Electromyogr Kinesiol 2013; 23:1036-43. [DOI: 10.1016/j.jelekin.2013.07.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2013] [Revised: 07/04/2013] [Accepted: 07/05/2013] [Indexed: 11/26/2022] Open
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38
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Stirn I, Jarm T, Kapus VP, Strojnik V. Evaluation of mean power spectral frequency of EMG signal during 100 metre crawl. Eur J Sport Sci 2013. [DOI: 10.1080/17461391.2011.630100] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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Mannion AF, Dolan P. The effects of muscle length and force output on the EMG power spectrum of the erector spinae. J Electromyogr Kinesiol 2012; 6:159-68. [PMID: 20719673 DOI: 10.1016/1050-6411(95)00028-3] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/1995] [Revised: 08/02/1995] [Accepted: 08/17/1995] [Indexed: 10/18/2022] Open
Abstract
In many skeletal muscles the myoelectric power spectrum median frequency (MF) increases with increasing force output, possibly reflecting the greater size and conduction velocity of the later-recruited (fast twitch) fibres. Muscles, such as the erector spinae, in which fast twitch fibres are smaller than slow twitch, may display an atypical relationship between force output and median frequency. The present study sought to investigate this possibility. Ten healthy men held forces ranging from 20-80% maximal voluntary contraction (MVC) of the back extensors for 4-6 s, at muscle lengths corresponding to 30, 60 and 90% of the lumbar spine's range of flexion (ROF). MF was determined from surface electromyograms recorded from thoracic and lumbar regions of the erector spinae. In each region, MF was significantly higher at 30% ROF (short muscle length) than at 60 or 90% ROF (P < 0.005) and slightly (but not significantly) higher at 60 than 90% ROF. The muscle length effect on MF may reflect a reduction in conduction velocity of the stretched and narrowed muscle fibres. Force output had a significant effect on MF (P < 0.0004), although the shape of the relationship differed between the two levels of the erector spinae: in the thoracic region MF increased with force up to 40-50% MVC and then levelled off, whereas in the lumbar region MF was relatively stable up to 30-40% MVC and then declined with increasing force. The results suggest that the mean fibre size of the later recruited motor units is, in the thoracic region, larger, and in the lumbar region, smaller, than that of the earlier-recruited motor units.
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Affiliation(s)
- A F Mannion
- Department of Anatomy, University of Bristol, Bristol, U.K
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40
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Peñailillo L, Silvestre R, Nosaka K. Changes in surface EMG assessed by discrete wavelet transform during maximal isometric voluntary contractions following supramaximal cycling. Eur J Appl Physiol 2012; 113:895-904. [PMID: 23001683 DOI: 10.1007/s00421-012-2499-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2012] [Accepted: 09/11/2012] [Indexed: 10/27/2022]
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Moslem B, Karlsson B, Diab MO, Khalil M, Marque C. Classification performance of the frequency-related parameters derived from uterine EMG signals. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2012; 2011:3371-4. [PMID: 22255062 DOI: 10.1109/iembs.2011.6090913] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Frequency-related parameters derived from the uterine electromyogram (EMG) signals are widely used in many pregnancy monitoring and preterm delivery prediction studies. Although they are classical parameters, they are well suited for quantifying uterine EMG signals and have many advantages over amplitude-related parameters. The present work aims to compare various frequency-related parameters according to their classification performances (pregnancy vs. labor) using the receiver operating characteristic (ROC) curve analysis. The comparison between the parameters indicates that median frequency is the best frequency-related parameter that can be used for distinguishing between pregnancy and labor contractions. We conclude that median frequency can be the representative frequency-related parameter for classification problems of uterine EMG.
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Affiliation(s)
- B Moslem
- Laboratoire Biomécanique et Bio-ingénierie, University of Technology of Compiègne – CNRS UMR 6600, Compiègne, Cedex, France.
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McSharry D, O'Connor C, McNicholas T, Langran S, O'Sullivan M, Lowery M, McNicholas WT. Genioglossus fatigue in obstructive sleep apnea. Respir Physiol Neurobiol 2012; 183:59-66. [PMID: 22677657 DOI: 10.1016/j.resp.2012.05.024] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2012] [Revised: 05/29/2012] [Accepted: 05/29/2012] [Indexed: 11/17/2022]
Abstract
Obstructive sleep apnea (OSA) is a prevalent disorder that may cause cardiovascular disease and fatal traffic accidents but the pathophysiology remains incompletely understood. Increased fatigability of the genioglossus (the principal upper airway dilator muscle) might be important in OSA pathophysiology but the existing literature is uncertain. We hypothesized that the genioglossus in OSA subjects would fatigue more than in controls. In 9 OSA subjects and 9 controls during wakefulness we measured maximum voluntary tongue protrusion force (Tpmax). Using surface electromyography arrays we measured the rate of decline in muscle fiber conduction velocity (MFCV) during an isometric fatiguing contraction at 30% Tpmax. The rate of decline in MFCV provides an objective means of quantifying localized muscle fatigue. Linear regression analysis of individual subject data demonstrated a significantly greater decrease in MFCV in OSA subjects compared to control subjects (29.2 ± 20.8% [mean ± SD] versus 11.2 ± 20.8%; p=0.04). These data support increased fatigability of the genioglossus muscle in OSA subjects which may be important in the pathophysiology of OSA.
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Affiliation(s)
- David McSharry
- Sleep Research Laboratory, St. Vincent's University Hospital, Dublin, Ireland.
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Dimitrov VG, Arabadzhiev TI, Dimitrova NA, Dimitrov GV. The spectral changes in EMG during a second bout eccentric contraction could be due to adaptation in muscle fibres themselves: a simulation study. Eur J Appl Physiol 2011; 112:1399-409. [PMID: 21818623 DOI: 10.1007/s00421-011-2095-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2011] [Accepted: 07/20/2011] [Indexed: 11/29/2022]
Abstract
The mechanism of marked reduction in damage symptoms after repeated bout of similar eccentric contractions is still unknown. The neuronal adaptation leading to reduction of muscle fibre propagation velocity (MFPV) due to increased activation of slow-twitch motor units (MUs), decrease in activation of fast-twitch MUs, and/or increase in MU synchronization was suggested as a cause for lower EMG frequency characteristics. However, the repeated bout effect could occur also after electrically stimulated exercise. Prolonged elevation of cytoplasmic Ca(2+) due to the increased membrane permeability after eccentric contractions was reported. Elevated Ca(2+) induced peripheral changes that included alteration of intracellular action potential and MFPV reduction. We simulated and compared changes in EMG frequency characteristics related to effects of central nervous system (CNS) or to peripheral changes. The simulations were performed for different electrode arrangements and positions. The results showed that the peripheral effects could be similar or even stronger than the effects related to CNS. We hypothesised that the repeated bout effect was a consequence of the adaptation in muscle fibres necessary for avoiding Ca(2+)-induced protein and lipid degradation due to Ca(2+) overload resulting from the increased membrane permeability after eccentric contraction. The possibilities for noninvasive testing of this hypothesis were discussed.
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Affiliation(s)
- V G Dimitrov
- Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Acad. G.Bonchev Str., Bl. 21, 1113 Sofia, Bulgaria.
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44
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Tscharner VV, Barandun M, Stirling LM. Piper rhythm of the electromyograms of the abductor pollicis brevis muscle during isometric contractions. J Electromyogr Kinesiol 2011; 21:184-9. [DOI: 10.1016/j.jelekin.2010.10.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2009] [Revised: 10/10/2010] [Accepted: 10/11/2010] [Indexed: 10/18/2022] Open
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von Tscharner V, Barandun M, Stirling LM. Fatigue-related decrease in Piper rhythm frequency of the abductor pollicis brevis muscle during isometric contractions. J Electromyogr Kinesiol 2011; 21:190-5. [DOI: 10.1016/j.jelekin.2010.10.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2010] [Revised: 08/08/2010] [Accepted: 10/12/2010] [Indexed: 11/25/2022] Open
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Qi L, Wakeling JM, Green A, Lambrecht K, Ferguson-Pell M. Spectral properties of electromyographic and mechanomyographic signals during isometric ramp and step contractions in biceps brachii. J Electromyogr Kinesiol 2010; 21:128-35. [PMID: 21067944 DOI: 10.1016/j.jelekin.2010.09.006] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2010] [Revised: 06/18/2010] [Accepted: 09/14/2010] [Indexed: 10/18/2022] Open
Abstract
The purposes of this study were: (1) to apply wavelet and principal component analysis to quantify the spectral properties of the surface EMG and MMG signals from biceps brachii during isometric ramp and step muscle contractions when the motor units are recruited in an orderly manner, and (2) to compare the recruitment patterns of motor unit during isometric ramp and step muscle contractions. Twenty healthy participants (age = 34 ± 10.7 years) performed step and ramped isometric contractions. Surface EMG and MMG were recorded from biceps brachii. The EMGs and MMGs were decomposed into their intensities in time-frequency space using a wavelet technique. The EMG and MMG spectra were then compared using principal component analysis (PCA) and ANCOVA. Wavelet combined PCA offers a quantitative measure of the contribution of high and low frequency content within the EMG and MMG. The ANCOVA indicated that there was no significant difference in EMG total intensity, EMG(MPF), first and second principal component loading scores (PCI and PCII) between ramp and step contractions, whereas the MMG(MPF) and MMG PCI loading scores were significantly higher during ramp contractions than during step contractions. These findings suggested that EMG and MMG may offer complimentary information regarding the interactions between motor unit recruitment and firing rate that control muscle force production. In addition, our results support the hypothesis that different motor unit recruitment strategy was used by the muscle when contracting under different conditions.
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Affiliation(s)
- Liping Qi
- ASPIRE Centre for Disability Sciences, Institute of Orthopedics and Musculoskeletal Science, University College London, Brockley Hill, Stanmore, London HA7 4LP, UK
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Kallenberg LAC, Hermens HJ. Motor unit properties of biceps brachii during dynamic contractions in chronic stroke patients. Muscle Nerve 2010; 43:112-9. [PMID: 20928907 DOI: 10.1002/mus.21803] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/25/2010] [Indexed: 11/06/2022]
Abstract
The aim of this study was to investigate motor unit (MU) characteristics of the biceps brachii during sinusoidal contractions in chronic stroke patients using high-density surface electromyography. Ten sinusoidal elbow flexion and extension movements were performed both passively and actively by 18 stroke patients and 20 healthy subjects. Motor unit action potentials (MUAPs) were extracted, and their root-mean-square value (RMS(MUAP)) was calculated. RMS(MUAP) was significantly larger in stroke than in healthy subjects. In both groups RMS(MUAP) was smaller during the stretch phase of passive movement than during active movement. The larger MUAPs indicate enlarged MUs, possibly as a result of reinnervation. The lower RMS(MUAP) values during passive stretch than during active movement indicates that the stretch reflex mainly activates smaller MUs, while a larger part of the MU pool can be recruited voluntarily. RMS(MUAP) may have added value for monitoring changes in peripheral MU properties after stroke.
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Affiliation(s)
- Laura A C Kallenberg
- Roessingh Research and Development, PO Box 310, 7500 AH Enschede, The Netherlands.
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Stirn I, Jarm T, Kapus V, Strojnik V. Evaluation of muscle fatigue during 100-m front crawl. Eur J Appl Physiol 2010; 111:101-13. [DOI: 10.1007/s00421-010-1624-2] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/17/2010] [Indexed: 11/24/2022]
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Karabulut M, Cramer JT, Abe T, Sato Y, Bemben MG. Neuromuscular fatigue following low-intensity dynamic exercise with externally applied vascular restriction. J Electromyogr Kinesiol 2010; 20:440-7. [PMID: 19640732 DOI: 10.1016/j.jelekin.2009.06.005] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2009] [Revised: 06/23/2009] [Accepted: 06/25/2009] [Indexed: 11/29/2022] Open
Affiliation(s)
- Murat Karabulut
- Department of Health and Human Performance, University of Texas at Brownsville/Texas Southmost College, TX 78520, USA.
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Prosser LA, Lee SCK, Barbe MF, VanSant AF, Lauer RT. Trunk and hip muscle activity in early walkers with and without cerebral palsy--a frequency analysis. J Electromyogr Kinesiol 2010; 20:851-9. [PMID: 20472460 DOI: 10.1016/j.jelekin.2010.04.005] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2009] [Revised: 04/14/2010] [Accepted: 04/15/2010] [Indexed: 10/19/2022] Open
Abstract
Poor control of postural muscles is a primary impairment in cerebral palsy (CP), yet core trunk and hip muscle activity has not been thoroughly investigated. Frequency analysis of electromyographic (EMG) signals provides insight about the intensity and pattern of muscle activation, correlates with functional measures in CP, and is sensitive to change after intervention. The objective of this study was to investigate differences in trunk and hip muscle activation frequency in children with CP compared to children with similar amounts of walking experience and typical development (TD). EMG data from 31 children (15 with CP, 16 with TD) were recorded from 16 trunk and hip muscles bilaterally. A time-frequency pattern was generated using the continuous wavelet transform and instantaneous mean frequency (IMNF) was calculated at each interval of the gait cycle. Functional principal component analysis (PCA) revealed that IMNF was significantly higher in the CP group throughout the gait cycle for all muscles. Additionally, stride-to-stride variability was higher in the CP group. This evidence demonstrated altered patterns of trunk and hip muscle activation in CP, including increased rates of motor unit firing, increased number of recruited motor units, and/or decreased synchrony of motor units. These altered muscle activation patterns likely contribute to muscle fatigue and decreased biomechanical efficiency in children with CP.
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Affiliation(s)
- Laura A Prosser
- Rehabilitation Medicine Department, National Institutes of Health, Bethesda, MD 20892, United States
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