Influence of fatigue on the simulated relation between the amplitude of the surface electromyogram and muscle force. 2010

Jakob L Dideriksen, and Dario Farina, and Roger M Enoka
Center for Sensory-Motor Interaction (SMI), Department of Health Science and Technology, Aalborg University, , Fredrik Bajers Vej 7 D-3, DK-9220 Aalborg, Denmark.

A linear relation between surface electromyogram (EMG) amplitude and muscle force is often assumed and used to estimate the contributions of selected muscles to various tasks. In the presence of muscle fatigue, however, changes in the properties of muscle fibre action potentials and motor unit twitch forces can alter the relation between surface EMG amplitude and force. A novel integrative model of motor neuron control and the generation of muscle fibre action potentials was used to simulate surface EMG signals and muscle force during three fatigue protocols. The change in the simulated relation between surface EMG amplitude and force depended on both the level of fatigue and the details of the fatiguing contraction. In general, surface EMG amplitude overestimated muscle force when fatigue was present. For example, surface EMG amplitudes corresponding to 60 per cent of the amplitude obtained at maximal force without fatigue corresponded to forces in the range 10-40% of the maximal force across three representative fatigue protocols. The results indicate that the surface EMG amplitude cannot be used to predict either the level of muscle activation or the magnitude of muscle force when the muscle exhibits any fatigue.

UI MeSH Term Description Entries
D008954 Models, Biological Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment. Biological Model,Biological Models,Model, Biological,Models, Biologic,Biologic Model,Biologic Models,Model, Biologic
D009119 Muscle Contraction A process leading to shortening and/or development of tension in muscle tissue. Muscle contraction occurs by a sliding filament mechanism whereby actin filaments slide inward among the myosin filaments. Inotropism,Muscular Contraction,Contraction, Muscle,Contraction, Muscular,Contractions, Muscle,Contractions, Muscular,Inotropisms,Muscle Contractions,Muscular Contractions
D003198 Computer Simulation Computer-based representation of physical systems and phenomena such as chemical processes. Computational Modeling,Computational Modelling,Computer Models,In silico Modeling,In silico Models,In silico Simulation,Models, Computer,Computerized Models,Computer Model,Computer Simulations,Computerized Model,In silico Model,Model, Computer,Model, Computerized,Model, In silico,Modeling, Computational,Modeling, In silico,Modelling, Computational,Simulation, Computer,Simulation, In silico,Simulations, Computer
D004576 Electromyography Recording of the changes in electric potential of muscle by means of surface or needle electrodes. Electromyogram,Surface Electromyography,Electromyograms,Electromyographies,Electromyographies, Surface,Electromyography, Surface,Surface Electromyographies
D006801 Humans Members of the species Homo sapiens. Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000465 Algorithms A procedure consisting of a sequence of algebraic formulas and/or logical steps to calculate or determine a given task. Algorithm
D013314 Stress, Mechanical A purely physical condition which exists within any material because of strain or deformation by external forces or by non-uniform thermal expansion; expressed quantitatively in units of force per unit area. Mechanical Stress,Mechanical Stresses,Stresses, Mechanical
D018482 Muscle, Skeletal A subtype of striated muscle, attached by TENDONS to the SKELETON. Skeletal muscles are innervated and their movement can be consciously controlled. They are also called voluntary muscles. Anterior Tibial Muscle,Gastrocnemius Muscle,Muscle, Voluntary,Plantaris Muscle,Skeletal Muscle,Soleus Muscle,Muscle, Anterior Tibial,Muscle, Gastrocnemius,Muscle, Plantaris,Muscle, Soleus,Muscles, Skeletal,Muscles, Voluntary,Skeletal Muscles,Tibial Muscle, Anterior,Voluntary Muscle,Voluntary Muscles
D018763 Muscle Fatigue A state arrived at through prolonged and strong contraction of a muscle. Studies in athletes during prolonged submaximal exercise have shown that muscle fatigue increases in almost direct proportion to the rate of muscle glycogen depletion. Muscle fatigue in short-term maximal exercise is associated with oxygen lack and an increased level of blood and muscle lactic acid, and an accompanying increase in hydrogen-ion concentration in the exercised muscle. Fatigue, Muscle,Muscular Fatigue,Fatigue, Muscular

Related Publications

Jakob L Dideriksen, and Dario Farina, and Roger M Enoka
January 2005, Journal of applied physiology (Bethesda, Md. : 1985),
Jakob L Dideriksen, and Dario Farina, and Roger M Enoka
September 1985, Journal of applied physiology (Bethesda, Md. : 1985),
Jakob L Dideriksen, and Dario Farina, and Roger M Enoka
April 1975, The Journal of physiology,
Jakob L Dideriksen, and Dario Farina, and Roger M Enoka
January 2018, BioMed research international,
Jakob L Dideriksen, and Dario Farina, and Roger M Enoka
September 1997, Sportverletzung Sportschaden : Organ der Gesellschaft fur Orthopadisch-Traumatologische Sportmedizin,
Jakob L Dideriksen, and Dario Farina, and Roger M Enoka
January 2014, BioMed research international,
Jakob L Dideriksen, and Dario Farina, and Roger M Enoka
April 1986, Journal of applied physiology (Bethesda, Md. : 1985),
Jakob L Dideriksen, and Dario Farina, and Roger M Enoka
September 1962, Rodo kagaku. The Journal of science of labour,
Jakob L Dideriksen, and Dario Farina, and Roger M Enoka
January 1989, The Journal of physiology,
Copied contents to your clipboard!