{
  "abstract": "Feedforward control is impaired after stroke, but whether practice improves it in the chronic stage remains unclear. In fast single-joint movements, feedforward control scales initial acceleration to movement amplitude. Feedback-error-learning theory predicts that fast practice should promote recalibration. We tested whether speed-emphasized reach training improved this scaling in the more-affected arm. Thirty-six individuals with mild-to-moderate chronic stroke completed 2,080 reaches over four sessions emphasizing Speed (n = 17) or Accuracy (n = 19). At baseline, 3 days, and 1 month after training, participants performed single-joint elbow movements of three amplitudes without online visual feedback. The slope relating initial peak acceleration to target amplitude quantified feedforward scaling. At baseline, scaling was reduced on the more-affected side for extension ({Delta}{beta} = -17.1 {+/-} 3.5 s-{superscript 2}, P < 0.001) and flexion ({Delta}{beta} = -21.9 {+/-} 3.2 s-{superscript 2}, P < 0.001). Speed training increased flexion scaling at 3 days ({Delta}{beta} = 14.7 {+/-} 3.6 s-{superscript 2}, P = 0.00029), with 14 of 17 participants improving. The group-by-session interaction showed a greater increase after Speed than Accuracy training ({Delta}{beta} = 14.13 {+/-} 4.9 s-{superscript 2}, P = 0.0053). Scaling declined by 1 month (P = 0.02); no training-related changes occurred for extension. Peak acceleration occurred within 100 ms. Time to peak velocity, an index of pulse width, showed no group-specific training effect. Thus, speed-emphasized training produced a short-term improvement in early flexion acceleration scaling that transferred to an untrained single-joint task and was consistent with improved feedforward control. Transfer primarily reflected acceleration pulse-height rather than pulse-width modulation.",
  "abstract_shown": true,
  "affiliations": [
    "Biokinesiology & Physical Therapy, University of Southern California, Los Angeles, CA, USA"
  ],
  "article_type": "PUBLISHAHEADOFPRINT",
  "arxiv": null,
  "author_total": 8,
  "authors": [
    {
      "name": "Y. Darmon"
    },
    {
      "name": "G. Hayrapetian"
    },
    {
      "name": "S. Kantak"
    },
    {
      "name": "V. R. Barradas"
    },
    {
      "name": "G. E. Loeb"
    },
    {
      "name": "C. Winstein"
    },
    {
      "name": "E. R. Rosario"
    },
    {
      "affs": [
        0
      ],
      "name": "N. Schweighofer"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/e46rfbtdc1h74.bib",
  "cited_by": 0,
  "doi": "10.64898/2026.10.02.26364609",
  "fulltext_url": "https://www.medrxiv.org/content/10.64898/2026.10.02.26364609v1.full",
  "id": "e46rfbtdc1h74",
  "issns": [],
  "landing_url": "https://www.medrxiv.org/content/10.64898/2026.10.02.26364609v1",
  "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",
      "2742|Stroke Rehabilitation and Recovery"
    ]
  ],
  "openalex": "W7220391019",
  "pdf_url": "https://www.medrxiv.org/content/10.64898/2026.10.02.26364609v1.full.pdf",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-02",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/e46rfbtdc1h74.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:20:07Z",
      "native_id": "10.64898/2026.10.02.26364609",
      "source": "medrxiv",
      "url": "https://www.medrxiv.org/content/10.64898/2026.10.02.26364609v1"
    }
  ],
  "subjects": [
    {
      "field": "medicine",
      "origin": "medrxiv:neurology",
      "subfield": "neurology"
    }
  ],
  "title": "Speed-emphasized arm training is consistent with improved feedforward control of rapid elbow flexion in chronic stroke",
  "title_text": "Speed-emphasized arm training is consistent with improved feedforward control of rapid elbow flexion in chronic stroke",
  "type": "preprint",
  "updated_at": "2026-10-30T12:20:07Z",
  "url": "https://research.draconitic.com/paper/e46rfbtdc1h74",
  "venue": "medRxiv",
  "versions": []
}