{
  "abstract": "Fiber-type composition contributes to contractile behavior and fatigue resistance. Characterizing these physiological differences could help study and monitor disease-related changes. Direct fiber-type measurement requires biopsy, whereas animal findings may not fully translate to humans. High-density surface electromyography (HD-sEMG) may offer repeatable, noninvasive assessment. We recorded HD-sEMG from tibialis anterior (TA) and soleus, muscles with contrasting fast- and slow-twitch-like physiology, during sustained contractions at 30% and 50% maximum voluntary contraction in participants with amyotrophic lateral sclerosis (ALS; n = 7) and healthy controls (n = 10). Given fast-fatigable motor unit vulnerability in ALS models, we compared TA-soleus profiles and fatigue-related changes. Amplitude, spectral, motor unit firing, and motor unit action potential (MUAP) features were quantified in the first 10 s of stable contraction, with firing and MUAP features derived from decomposition. Exploratory fatigue analyses assessed early-to-late changes and trajectories. Early-window root mean square (RMS), spectral power, firing rate, and MUAP amplitude were higher in TA than soleus in both groups. Group x Muscle interactions were nonsignificant. Despite higher early values, TA showed larger fatigue-related declines in high-frequency power, RMS, and firing rate than soleus, particularly in ALS-affected TA. These findings suggest HD-sEMG detects muscle-type-related electrophysiological differences, with ALS-related changes more evident during fatigue.",
  "abstract_shown": true,
  "affiliations": [
    "University of Pittsburgh"
  ],
  "article_type": "PUBLISHAHEADOFPRINT",
  "arxiv": null,
  "author_total": 7,
  "authors": [
    {
      "name": "E. H. Bedoy"
    },
    {
      "name": "M. Brown"
    },
    {
      "name": "B. Sullivan"
    },
    {
      "name": "M. A. Christofidis"
    },
    {
      "name": "T. Al-Lahham"
    },
    {
      "name": "D. Weber"
    },
    {
      "affs": [
        0
      ],
      "name": "C. L. Kolarcik"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/ezqffn81vmdk9.bib",
  "cited_by": 0,
  "doi": "10.64898/2026.10.20.26366045",
  "fulltext_url": "https://www.medrxiv.org/content/10.64898/2026.10.20.26366045v1.full",
  "id": "ezqffn81vmdk9",
  "issns": [],
  "landing_url": "https://www.medrxiv.org/content/10.64898/2026.10.20.26366045v1",
  "language": null,
  "licence": "CC-BY-NC-ND",
  "licence_label": "CC BY-NC-ND",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by-nc-nd/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "medrxiv",
      "neurology"
    ],
    [
      "openalex",
      "2204|Muscle activation and electromyography studies"
    ]
  ],
  "openalex": "W7223229374",
  "pdf_url": "https://www.medrxiv.org/content/10.64898/2026.10.20.26366045v1.full.pdf",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-20",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/ezqffn81vmdk9.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:21:28Z",
      "native_id": "10.64898/2026.10.20.26366045",
      "source": "medrxiv",
      "url": "https://www.medrxiv.org/content/10.64898/2026.10.20.26366045v1"
    }
  ],
  "subjects": [
    {
      "field": "medicine",
      "origin": "medrxiv:neurology",
      "subfield": "neurology"
    }
  ],
  "title": "High-Density Surface Electromyography Detects Fiber-Type-Related Profiles and Disease-Relevant Fatigue Trajectories in Amyotrophic Lateral Sclerosis",
  "title_text": "High-Density Surface Electromyography Detects Fiber-Type-Related Profiles and Disease-Relevant Fatigue Trajectories in Amyotrophic Lateral Sclerosis",
  "type": "preprint",
  "updated_at": "2026-10-30T12:21:28Z",
  "url": "https://research.draconitic.com/paper/ezqffn81vmdk9",
  "venue": "medRxiv",
  "versions": []
}