{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,9]],"date-time":"2026-09-09T05:36:26Z","timestamp":1788932186556,"version":"build-2803163510"},"reference-count":48,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2024,12,4]],"date-time":"2024-12-04T00:00:00Z","timestamp":1733270400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Muscles"],"abstract":"<jats:p>Background: Surface mechanomyographic (sMMG) signals have been used to examine sex-specific differences in the mechanical behavior of muscle during fatiguing exercise. However, studies often utilize simple amplitude- and frequency-based analyses, which only reveal the static components of the sMMG signal. Methods: Thus, a wavelet-based analysis was used to examine changes in the spectral intensity of the non-dominant limb\u2019s vastus lateralis during a fatiguing, maximal, unilateral isometric leg extension in recreationally active men (n = 11) and women (n = 10). Relative changes in spectral intensities and instantaneous mean frequency (IMF) were examined using linear mixed-effect models. Time-to-task failure was compared using an independent sample t-test. Results: The neuromuscular responses demonstrated parallel decreases in IMF (p &lt; 0.001). Further, there were parallel, nonlinear, decreases in spectral intensity across wavelets (p &lt; 0.001) and there were no sex differences in time-to-task failure (p = 0.15). Conclusions: These data showed no sex-specific differences in exercise fatigability or muscle mechanics during fatiguing exercise of the leg extensors. However, when collapsed across sex, wavelet-specific changes in spectral intensity over time reveal novel insights into the interplay between low- and high-frequency components during fatigue.<\/jats:p>","DOI":"10.3390\/muscles3040035","type":"journal-article","created":{"date-parts":[[2024,12,4]],"date-time":"2024-12-04T11:03:08Z","timestamp":1733310188000},"page":"417-430","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Examination of Sex-Related Differences in Fatigability and Frequency Components of Mechanomyographic Signals During Sustained Exercise"],"prefix":"10.3390","volume":"3","author":[{"given":"Brian","family":"Benitez","sequence":"first","affiliation":[{"name":"Department of Kinesiology and Health Promotion, University of Kentucky, Lexington, KY 40536, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Minyoung","family":"Kwak","sequence":"additional","affiliation":[{"name":"Department of Kinesiology and Health Promotion, University of Kentucky, Lexington, KY 40536, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pasquale J.","family":"Succi","sequence":"additional","affiliation":[{"name":"Department of Kinesiology and Health Promotion, University of Kentucky, Lexington, KY 40536, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Clara J.","family":"Mitchinson","sequence":"additional","affiliation":[{"name":"Department of Kinesiology and Health Promotion, University of Kentucky, Lexington, KY 40536, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Haley C.","family":"Bergstrom","sequence":"additional","affiliation":[{"name":"Department of Kinesiology and Health Promotion, University of Kentucky, Lexington, KY 40536, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,12,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.jelekin.2005.12.002","article-title":"Does the Frequency Content of the Surface Mechanomyographic Signal Reflect Motor Unit Firing Rates? 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