{
  "abstract": "Objectives and design: This exploratory single-case study examined whether repeated attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy of blood plasma is technically feasible during a short pre-competition period and whether spectral regions co-vary with conventionally assayed biochemical markers.\n\nMethods: One professional heavyweight boxer was monitored over a 13-day pre-competition period characterized by reduced training load (tapering). Morning fasting blood was collected on five occasions (10, 13, 17, 20, and 23 May 2024) into lithium-heparin tubes and centrifuged to obtain plasma. Creatine kinase (CK), C-reactive protein (CRP), glucose, cortisol, testosterone, total and reduced glutathione, malondialdehyde, and zinc were quantified by conventional laboratory assays; ATR-FTIR spectra were acquired separately from the same plasma aliquots and were not used to quantify any of these analytes. Each plasma sample was measured eight times, yielding 40 spectra from five biological observations; the technical replicates are presented to illustrate within-sample visual consistency. Associations between the intensities of 22 spectral peaks and 12 biochemical variables were explored using Pearson correlation.\n\nResults: Plasma biochemical parameters showed changes during the pre-competition tapering period, including decreases in CK and CRP and increases in glutathione and testosterone, whereas cortisol remained relatively stable. FTIR spectra exhibited consistent vibrational profiles with changes in selected band intensities over time. Linear regression identified strong associations between glutathione levels and FTIR bands at 671, 699, and 721 cm−1 (R2 = 0.80–0.92), as well as between cortisol and the 3,009 cm−1 band (R2 = 0.77). Because of the limited number of observations (n = 5), these findings are preliminary and require validation in larger cohorts.\n\nConclusions: Repeated plasma measurements using ATR-FTIR demonstrated technical feasibility and visual consistency during a short pre-competition period in the studied athlete, while identifying potential spectral regions worthy of further investigation. The obtained results should be treated as preliminary. However, they do not provide evidence that ATR-FTIR enables the quantitative determination of glutathione or cortisol, or that it can be used to assess an athlete’s competitive readiness. Confirmation of such capabilities requires studies involving adequately large and diverse groups of participants.",
  "abstract_shown": true,
  "affiliations": [
    "Faculty of Physical Culture Sciences, College of Medical Sciences, University of Rzeszow , ,",
    "Institute of Nuclear Physics, Polish Academy of Sciences , ,",
    "Department of Dermatology, Faculty of Medicine, Collegium Medicum, University of Rzeszow , ,",
    "Institute of Physics, Faculty of Exact and Technical Sciences, University of Rzeszow , ,",
    "Department of Endocrinology, Institute of Sport-National Research Institute , ,",
    "Department of Sport Theory and Motor Skills, Institute of Sport Sciences, University of Physical Culture in Kraków , ,"
  ],
  "article_type": "research article",
  "arxiv": null,
  "author_total": 9,
  "authors": [
    {
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        0
      ],
      "name": "Paweł Król"
    },
    {
      "affs": [
        1
      ],
      "name": "Joanna Depciuch"
    },
    {
      "affs": [
        2
      ],
      "name": "Adam Reich"
    },
    {
      "affs": [
        3
      ],
      "name": "Józef Cebulski"
    },
    {
      "affs": [
        4
      ],
      "name": "Zbigniew Obmiński"
    },
    {
      "affs": [
        5
      ],
      "name": "Krzysztof Kasicki"
    },
    {
      "affs": [
        0
      ],
      "name": "Wojciech Czarny"
    },
    {
      "affs": [
        0
      ],
      "name": "Łukasz Różański"
    },
    {
      "affs": [
        5
      ],
      "name": "Łukasz Rydzik"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/2ezh64h9ajbme.bib",
  "cited_by": 0,
  "doi": "10.3389/fphys.2026.1845333",
  "fulltext_url": "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13724598/?tool=EBI",
  "id": "2ezh64h9ajbme",
  "issns": [
    "1664-042X"
  ],
  "landing_url": "https://europepmc.org/article/PMC/PMC13724598",
  "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": [
    [
      "heading",
      "Original Research"
    ],
    [
      "openalex",
      "1304|Spectroscopy Techniques in Biomedical and Chemical Research"
    ]
  ],
  "openalex": "W7222954395",
  "pdf_url": "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13724598/pdf/?tool=EBI",
  "pmcid": "PMC13724598",
  "pmid": "42973887",
  "published": "2026-10-19",
  "publisher": "Frontiers Media SA",
  "ris": "https://research.draconitic.com/paper/2ezh64h9ajbme.ris",
  "sources": [
    {
      "first_seen": "2026-11-03T15:20:51Z",
      "native_id": "PMC:PMC13724598",
      "source": "europepmc",
      "url": "https://europepmc.org/article/PMC/PMC13724598"
    },
    {
      "first_seen": "2026-11-04T12:23:08Z",
      "native_id": "PMC13724598",
      "source": "pmc",
      "url": "https://doi.org/10.3389/fphys.2026.1845333"
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    {
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      "native_id": "MED:42973887",
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  "subjects": [
    {
      "field": "biochemistry",
      "origin": "openalex:1304|Spectroscopy Techniques in Biomedical and Chemical Research",
      "subfield": "biophysics"
    }
  ],
  "title": "Application of FTIR to detect changes in blood plasma during a pre-competition period in a professional heavyweight boxer",
  "title_text": "Application of FTIR to detect changes in blood plasma during a pre-competition period in a professional heavyweight boxer",
  "type": "peer-reviewed",
  "updated_at": "2026-11-05T12:21:19Z",
  "url": "https://research.draconitic.com/paper/2ezh64h9ajbme",
  "venue": "Frontiers in physiology",
  "versions": []
}