{
  "abstract": "Low energy availability (LEA) is commonly studied under tightly controlled laboratory conditions. However, its induction and monitoring in free-living athletes remain poorly understood, partly due to challenges in measuring energy intake (EI), exercise energy expenditure (EEE) and daily behavioural variability. This study examined whether a prescribed LEA intervention leads to a consistent energy deficit and described the variability in energy availability (EA) and associated physiological and performance responses. In this pilot case series with a repeated-measures control-intervention structure, trained male endurance athletes (n = 3) completed a 14-day intervention targeting LEA (~20 kcal (~84 kJ)·kg fat-free mass (FFM)⁻¹·day⁻¹) by increasing EEE while maintaining habitual EI. EA was estimated daily using image-based dietary assessment, heart rate-derived EEE and dual-energy X-ray absorptiometry-derived FFM; resting metabolic rate (RMR), performance and well-being were assessed pre- and post-intervention. Despite the target, achieved EA varied substantially within and between participants (day-to-day SD 7-20 kcal·kg FFM⁻¹·day⁻¹), reflecting the magnitude and distribution of EEE rather than a uniform deficiency. Responses were heterogeneous: RMR showed no consistent direction, haemoglobin decreased modestly in all athletes, body-composition changes were small, and performance ranged from decline to improvement. Mean EA interpreted in isolation may obscure intra-individual variability, indicating a need for methods that capture it in free-living research.",
  "abstract_shown": true,
  "affiliations": [
    "School of Allied Health, Curtin University, Bentley, WA 6102, Australia.",
    "School of Population Health, Curtin University, Bentley, WA 6102, Australia."
  ],
  "article_type": "research article",
  "arxiv": null,
  "author_total": 4,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Fabricio Forchino",
      "orcid": "0000-0001-9314-7199"
    },
    {
      "affs": [
        0
      ],
      "name": "Carly J Brade",
      "orcid": "0000-0001-9341-1412"
    },
    {
      "affs": [
        1
      ],
      "name": "Deborah A Kerr",
      "orcid": "0000-0002-1094-1299"
    },
    {
      "affs": [
        0
      ],
      "name": "Dale W Chapman",
      "orcid": "0000-0002-3393-1261"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/4rnrnv8ztssrg.bib",
  "cited_by": 0,
  "doi": "10.3390/sports14100446",
  "fulltext_url": "https://europepmc.org/articles/PMC13709522",
  "id": "4rnrnv8ztssrg",
  "issns": [
    "2075-4663"
  ],
  "landing_url": "https://europepmc.org/article/MED/42931583",
  "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": "W7221199074",
  "pdf_url": "https://europepmc.org/articles/PMC13709522?pdf=render",
  "pmcid": "PMC13709522",
  "pmid": "42931583",
  "published": "2026-10-09",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/4rnrnv8ztssrg.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:22:01Z",
      "native_id": "MED:42931583",
      "source": "europepmc",
      "url": "https://europepmc.org/article/MED/42931583"
    }
  ],
  "subjects": [
    {
      "field": "medicine",
      "origin": "openalex:2732|Sports Performance and Training",
      "subfield": "surgery"
    }
  ],
  "title": "Variable Energy Availability Exposure and Heterogeneous Physiological Responses to a Prescribed Low Energy Availability Intervention in Free-Living Male Endurance Athletes: A Pilot Case-Series.",
  "title_text": "Variable Energy Availability Exposure and Heterogeneous Physiological Responses to a Prescribed Low Energy Availability Intervention in Free-Living Male Endurance Athletes: A Pilot Case-Series.",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:22:01Z",
  "url": "https://research.draconitic.com/paper/4rnrnv8ztssrg",
  "venue": "Sports (Basel, Switzerland)",
  "versions": []
}