{
  "abstract": "Purpose Breast cancer remains the most common cancer among women and risk varies by race/ethnicity. Physical activity has been shown to reduce risk by 10–21% in White women but this reduction has not been established in other races/ethnicities. This study explores the association between physical activity and breast cancer risk in a large cohort of multiethnic women. Methods We analyzed data from 93,137 African American, White, Japanese American, Latina, and Native Hawaiian women who participated in the Hawaii-California Multiethnic Cohort Study. Data on physical activity (hours and METs) was based on a self-administered questionnaire at baseline (1993–1996) and a 10-year follow-up questionnaire (2003–2007). Multivariate Cox proportional hazards models provided estimates of hazard ratios (HRs) and 95% confidence intervals (CIs). Results We observed an inverse association between breast cancer risk and METs of total activity per day (HR = 0.92, 95% CI: 0.87–0.98, P trend =0.01) but not for total hours of moderate/vigorous activity per day (HR = 0.95, 95% CI: 0.89–1.02, P trend = 0.08) when comparing the highest quartile to the lowest in all women. After stratification, Latina women in the highest quartile of METs of total activity per day had a statistically significant reduction in breast cancer risk (HR = 0.84, 95% CI: 0.72–0.98, P trend =0.05) compared to the lowest quartile. For others, HRs were below one for the highest METs quartile; there was no evidence of heterogeneity across race/ethnicity (p = 0.76). Conclusion This research confirms an overall protective association between physical activity and breast cancer risk, and suggests protection across races/ethnicities.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": "research article",
  "arxiv": null,
  "author_total": 8,
  "authors": [
    {
      "name": "Jasmeet K. Gill"
    },
    {
      "name": "Chloe Holm"
    },
    {
      "name": "Song-Yi Park"
    },
    {
      "name": "Yurii Shvetsov"
    },
    {
      "name": "Christopher Haiman"
    },
    {
      "name": "Lynne R. Wilkens"
    },
    {
      "name": "Loïc LeMarchand"
    },
    {
      "name": "Gertraud Maskarinec"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/4wqgg6xmtf21w.bib",
  "cited_by": 0,
  "doi": "10.21203/rs.3.rs-11177770/v1",
  "fulltext_url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC13734262/",
  "id": "4wqgg6xmtf21w",
  "issns": [
    "2693-5015"
  ],
  "landing_url": "https://doi.org/10.21203/rs.3.rs-11177770/v1",
  "language": "en",
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "heading",
      "Article"
    ],
    [
      "openalex",
      "2730|Cancer Risks and Factors"
    ]
  ],
  "openalex": "W7223699155",
  "pdf_url": "https://www.researchsquare.com/article/rs-11177770/latest.pdf",
  "pmcid": "PMC13734262",
  "pmid": "42990784",
  "published": "2026-10-26",
  "publisher": "American Journal Experts",
  "ris": "https://research.draconitic.com/paper/4wqgg6xmtf21w.ris",
  "sources": [
    {
      "first_seen": "2026-11-08T12:23:53Z",
      "native_id": "PMC13734262",
      "source": "pmc",
      "url": "https://doi.org/10.21203/rs.3.rs-11177770/v1"
    }
  ],
  "subjects": [
    {
      "field": "medicine",
      "origin": "openalex:2730|Cancer Risks and Factors",
      "subfield": "oncology"
    }
  ],
  "title": "Physical activity and breast cancer in the Multiethnic Cohort Study",
  "title_text": "Physical activity and breast cancer in the Multiethnic Cohort Study",
  "type": "preprint",
  "updated_at": "2026-11-08T12:23:53Z",
  "url": "https://research.draconitic.com/paper/4wqgg6xmtf21w",
  "venue": "Research Square",
  "versions": []
}