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Published on: December 5, 2012
What do we learn from motor unit action potentials in surface electromyography?
Karin Roeleveld1, Dick F Stegeman
1Program for Sport Sciences, Faculty of Social Sciences and Technology Management, Norwegian University of Science and Technology, N-7491 Trondheim, Norway. karin.roeleveld@svt.ntnu.no
Abstract:
This article gives an overview of what multichannel surface electromyography can teach us about a motor unit. Background information is given about the generation of surface electromyography in general and surface motor unit potentials in particular. Furthermore, we describe how surface motor unit potentials are related to several motor unit characteristics, such as size, location, neuromuscular junction position, fiber length, fiber type, and metabolic fiber properties. In addition, we show how the spatial characteristics of multichannel surface electromyography can be used to obtain single-surface motor unit potentials. The possibilities, challenges, and problems are discussed. Finally, several examples of surface motor unit potential analyses are given.
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