Reliability of surface electromyography in estimating muscle fiber conduction velocity: A systematic review

The purpose of this study was to review the literature (1) to determine whether surface electromyography (sEMG) is a reliable tool for estimating muscle fiber conduction velocity (CV) and (2) to identify the experimental conditions that allow highly reliable CV estimation. A literature search was performed using PubMed and Web of Science databases using the terms "reproducibility", "reliability", "agreement", "surface electromyography" and "conduction velocity". Reporting quality was assessed using the "Guidelines for the Reporting of Reliability and Agreement Studies" checklist. Seventeen papers met the eligibility criteria. Test-retest, intrasession and intersession reliability were investigated in four, three and 12 studies, respectively. Although none of the studies satisfied all the relevant quality criteria, in fifteen studies, it was possible to locate an appropriate description for up to five items of the checklist. High reliability (intraclass correlation coefficient >0.69) was reported in eight studies and was, in general, associated with using the initial or mean CV value, using several electrodes (3 to 8), ensuring appropriate electrode positioning, and evaluating muscles with fibers that run parallel to the skin. Consequently, sEMG is suitable for use when investigating CV across multiple sessions in sport science, rehabilitation, physiological and clinical studies.