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Updated: Jul 25, 2026

Ex Vivo Assessment of Contractility, Fatigability and Alternans in Isolated Skeletal Muscles
Published on: November 1, 2012
[Electrical activity of muscles during disturbances in the trajectory of single-joint motion in the arm]
Abstract:
Horizontal "extension-flexion" movement of human arm at the elbow joint was studied. Humans performed movements in accordance with the instruction to ignore sudden trajectory changes that arose by the arm during lengthening of different elastic rods with friction. It was shown by multi-dimension regression analysis that the electric activity of biceps and triceps muscles of the shoulder was correlated first of all with the work of load and then with loading force, muscle work and other mechanic and myographic characteristics. One could suppose that information on energy quantities was contained in afferentation signals of the nervous system to correct the program commands on the spinal level. The purpose of correction was to preserve constant quantity of energy expenditure, as well as accuracy and duration of movement.
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