Last Word on Point:Counterpoint: Spectral properties of the surface EMG can characterize/do not provide information about motor unit recruitment strategies and muscle fiber type

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POINT-COUNTERPOINTLast Word on Point:Counterpoint: Spectral properties of the surface EMG can characterize/do not provide information about motor unit recruitment strategies and muscle fiber typeVinzenz von Tscharner, and Benno M. NiggVinzenz von Tscharner, and Benno M. NiggPublished Online:01 Nov 2008https://doi.org/10.1152/japplphysiol.91181.2008MoreSectionsPDF (22 KB)Download PDF ToolsExport citationAdd to favoritesGet permissionsTrack citations ShareShare onFacebookTwitterLinkedInEmailWeChat to the editor: A large number of researchers have constructively contributed to the debate (2). They addressed topics that because of the limited length of the article were left out and were therefore not discussed. However, one argument should be discussed here. Stegeman (see Ref. 1) argued in his comments that animal results should be taken with care. A type-frequency relationship emerged based solely on studies on animals and in accordance with classical views on interference EMG. The type-frequency relationship states that slow type I and fast type II fibers contribute more low- and high-frequency components to the power spectrum, respectively. Experimental evidence leads Wakeling (see Ref. 1) to warn that it is likely that this will not necessarily be the case for all physiological situations and restricted recruitment tasks. Merletti (see Ref. 1) in his comments presented conceivable cases where two groups of fibers could contribute to a result showing an inverted type-frequency relationship. In these examples, two groups of muscle fibers may be activated separately but the one consisting of type II fibers would generate more power at low frequencies and the one consisting of type I fibers would generate more power at high frequencies. Although Mayer (see Ref. 1), based on a very narrow view of wavelets, questions its usefulness in an unsubstantiated way, the presented time-frequency analysis would most likely be able to detect an inverted type-frequency condition. In fact, yet unpublished results were discussed in our laboratory that might be explained by an inverted type-frequency situation. One should therefore not be surprised finding inverted type-frequency situations in future studies and should openly discuss this possibility.REFERENCES1 Enoka RM, Bawa P, Wakeling JM, Gabriel DA, Kamen G, Meyer F, Stegeman DF, van Wessel T, Zwarts MJ, Rainoldi A, Dimitrova NA, Dimitrov GV, Merletti R, Creswell AG, Barry BK, Pincivero DM. Comments on Point:Counterpoint: Spectral properties of the surface EMG can characterize/do not provide information about motor unit recruitment strategies and muscle fiber type. J Appl Physiol; doi:10.1152/japplphysiol.zdg-8232-pcpcomm.2008.Link | ISI | Google Scholar2 Von Tscharner V, Nigg BM. Spectral properties of the surface EMG can characterize motor unit recruitment strategies and muscle fiber types. J Appl Physiol; doi:10.1152/japplphysiol.90598.2008.Link | ISI | Google Scholar Download PDF Previous Back to Top Next FiguresReferencesRelatedInformationCited ByThe Assessment of Muscular Effort, Fatigue, and Physiological Adaptation Using EMG and Wavelet Analysis11 August 2015 | PLOS ONE, Vol. 10, No. 8The extraction of neural strategies from the surface EMG: an updateDario Farina, Roberto Merletti, and Roger M. Enoka1 December 2014 | Journal of Applied Physiology, Vol. 117, No. 11Last Word on Point:Counterpoint: Spectral properties of the surface EMG can characterize/do not provide information about motor unit recruitment and muscle fiber typeDario Farina1 November 2008 | Journal of Applied Physiology, Vol. 105, No. 5 More from this issue > Volume 105Issue 5November 2008Pages 1682-1682 Copyright & PermissionsCopyright © 2008 the American Physiological Societyhttps://doi.org/10.1152/japplphysiol.91181.2008PubMed18984915History Published online 1 November 2008 Published in print 1 November 2008 Metrics