Biomaterial Database

Muscle fatigue in myophosphorylase deficiency: power spectral analysis of the electromyogram. 1984

K R Mills, and R H Edwards

It has been postulated that the power spectral shift in the surface EMG during fatigue is due to accumulation of muscle lactate. This hypothesis has been directly tested by measuring such shift in 3 patients with myophosphorylase deficiency who performed sustained isometric contractions of the quadriceps muscle. It was found that the spectral shift in these patients was greater than that in normal subjects, rendering lactate as a cause of this phenomenon very unlikely. The mechanism of excessive fatiguability in myophosphorylase deficiency is thought to be due to failure of excitation of the muscle membrane; further support for this postulate is provided and it is contended that accumulation of extracellular potassium ions may explain the phenomena of spectral shift in normals and myophosphorylase deficient patients and the excessive fatiguability in the latter.

UI	MeSH Term	Description	Entries
D008297	Male		Males
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
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
D005221	Fatigue	The state of weariness following a period of exertion, mental or physical, characterized by a decreased capacity for work and reduced efficiency to respond to stimuli.	Lassitude
D005260	Female		Females
D006005	Phosphorylases	A class of glucosyltransferases that catalyzes the degradation of storage polysaccharides, such as glucose polymers, by phosphorolysis in animals (GLYCOGEN PHOSPHORYLASE) and in plants (STARCH PHOSPHORYLASE).	Glucan Phosphorylase,Phosphorylase,alpha-Glucan Phosphorylases
D006012	Glycogen Storage Disease Type V	Glycogenosis due to muscle phosphorylase deficiency. Characterized by painful cramps following sustained exercise.	Glycogenosis 5,McArdle's Disease,Deficiency, Muscle Phosphorylase,Glycogen Storage Disease Type 5,Glycogen Storage Disease V,McArdle Disease,McArdle Type Glycogen Storage Disease,Mcardle Syndrome,Muscle Glycogen Phosphorylase Deficiency,Muscle Phosphorylase Deficiency,Myophosphorylase deficiency,PYGM Deficiency,Deficiencies, Muscle Phosphorylase,Deficiencies, PYGM,Deficiency, PYGM,Disease, McArdle,Disease, McArdle's,Glycogenosis 5s,McArdles Disease,Mcardle Syndromes,Muscle Phosphorylase Deficiencies,Myophosphorylase deficiencies,PYGM Deficiencies,Phosphorylase Deficiencies, Muscle,Phosphorylase Deficiency, Muscle,Syndrome, Mcardle,Syndromes, Mcardle,deficiencies, Myophosphorylase,deficiency, Myophosphorylase
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000328	Adult	A person having attained full growth or maturity. Adults are of 19 through 44 years of age. For a person between 19 and 24 years of age, YOUNG ADULT is available.	Adults