{
  "abstract": "Introduction\n\nTraining load, expressed as a percentage of one-repetition maximum (%1RM), is an important variable in resistance training. Prior studies comparing low- and high-load training on muscle fiber hypertrophy reported conflicting findings, and the load-specific relationship has not been analyzed in a continuous manner. This systematic review and meta-regression explored the relationship between training load and muscle fiber hypertrophy.Methods\n\nA systematic search was conducted in PubMed/MEDLINE, Scopus, and SPORTDiscus databases. Standardized mean changes (SMC) were calculated and analyzed using multilevel meta-regressions with cluster-robust variance estimation, with exploratory sensitivity and interacting moderator analyses. Eight studies involving 195 participants were included.Results\n\nIn the fiber-type specific model, pairwise contrast estimates were negative at low loads (20-30% 1RM: -0.147 to -0.088 SMC) and positive at higher loads (60-90% 1RM: 0.089-0.265 SMC). However, the 95% confidence intervals included zero for all pairwise contrasts.Conclusion\n\nThe observed model estimates suggested a potential fiber-type specific pattern across loading ranges. However, these findings should be considered preliminary and interpreted with caution given the small number of included studies and wide 95% confidence and prediction intervals, indicating a degree of uncertainty and imprecision.",
  "abstract_shown": true,
  "affiliations": [
    "Faculty of Kinesiology, University of Zagreb, Zagreb, Croatia.",
    "Department of Sports Science and Physical Education, Nord University, Levanger, Norway.",
    "Academy for Personal Training, Fredrikstad, Norway.",
    "Department of Sports Science and Physical Education, Faculty of Education, The Chinese University of Hong Kong, Hong Kong, Hong Kong SAR, China."
  ],
  "article_type": "systematic review",
  "arxiv": null,
  "author_total": 3,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Dorian Varovic"
    },
    {
      "affs": [
        1,
        2
      ],
      "name": "Stian Larsen"
    },
    {
      "affs": [
        3
      ],
      "name": "Jozo Grgic"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/722tznphm62pa.bib",
  "cited_by": 0,
  "doi": "10.3389/fphys.2026.1953601",
  "fulltext_url": "https://europepmc.org/articles/PMC13680249",
  "id": "722tznphm62pa",
  "issns": [
    "1664-042X"
  ],
  "landing_url": "https://europepmc.org/article/MED/42903128",
  "language": "eng",
  "licence": "CC-BY",
  "licence_label": "CC BY",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "openalex",
      "2732|Sports Performance and Training"
    ]
  ],
  "openalex": "W7161523155",
  "pdf_url": "https://europepmc.org/articles/PMC13680249?pdf=render",
  "pmcid": "PMC13680249",
  "pmid": "42903128",
  "published": "2026-10-06",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/722tznphm62pa.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:19:57Z",
      "native_id": "MED:42903128",
      "source": "europepmc",
      "url": "https://europepmc.org/article/MED/42903128"
    }
  ],
  "subjects": [
    {
      "field": "medicine",
      "origin": "openalex:2732|Sports Performance and Training",
      "subfield": "surgery"
    }
  ],
  "title": "Heavy or light: is muscle fiber growth load-specific? A systematic review and meta-regression.",
  "title_text": "Heavy or light: is muscle fiber growth load-specific? A systematic review and meta-regression.",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:19:57Z",
  "url": "https://research.draconitic.com/paper/722tznphm62pa",
  "venue": "Frontiers in physiology",
  "versions": []
}