{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,30]],"date-time":"2026-01-30T09:39:13Z","timestamp":1769765953911,"version":"3.49.0"},"reference-count":66,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2020,1,28]],"date-time":"2020-01-28T00:00:00Z","timestamp":1580169600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Diagnostics"],"abstract":"<jats:p>The impact of ultramarathon (UM) runs on the organs of competitors, especially elite individuals, is poorly understood. We tested a 36-year-old UM runner before, 1\u20132 days after, and 10\u201311 days after winning a 24-h UM as a part of the Polish Championships (258.228 km). During each testing session, we performed an electrocardiogram (ECG), transthoracic echocardiography (TTE), cardiac magnetic resonance imaging (MRI), cardiac 31P magnetic resonance spectroscopy (31P MRS), and blood tests. Initially, increased cholesterol and low-density lipoprotein cholesterol (LDL-C) levels were identified. The day after the UM, increased levels of white blood cells, neutrophils, fibrinogen, alanine aminotransferase, aspartate aminotransferase, creatine kinase, C-reactive protein, and N-terminal type B natriuretic propeptide were observed. Additionally, decreases in hemoglobin, hematocrit, cholesterol, LDL-C, and hyponatremia were observed. On day 10, all measurements returned to normal levels, and cholesterol and LDL-C returned to their baseline abnormal values. ECG, TTE, MRI, and 31P MRS remained within the normal ranges, demonstrating physiological adaptation to exercise. The transient changes in laboratory test results were typical for the extreme efforts of the athlete and most likely reflected transient but massive striated muscle damage, liver cell damage, activation of inflammatory processes, effects on the coagulation system, exercise-associated hyponatremia, and cytoprotective or growth-regulatory effects. These results indicated that many years of intensive endurance training and numerous UMs (including the last 24-h UM) did not have a permanent adverse effect on this world-class UM runner\u2019s body and heart. Transient post-competition anomalies in laboratory test results were typical of those commonly observed after UM efforts.<\/jats:p>","DOI":"10.3390\/diagnostics10020073","type":"journal-article","created":{"date-parts":[[2020,1,28]],"date-time":"2020-01-28T09:37:09Z","timestamp":1580204229000},"page":"73","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Heart of the World\u2019s Top Ultramarathon Runner\u2014Not Necessarily Much Different from Normal"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8305-8130","authenticated-orcid":false,"given":"Robert","family":"Gajda","sequence":"first","affiliation":[{"name":"Center for Sports Cardiology at the Gajda-Med Medical Center in Pu\u0142tusk, ul. Piotra Skargi 23\/29, 06-100 Pu\u0142tusk, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Anna","family":"Klisiewicz","sequence":"additional","affiliation":[{"name":"The Cardinal Stefan Wyszy\u0144ski National Institute of Cardiology, ul. Alpejska 42, 04-628 Warszawa, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Vadym","family":"Matsibora","sequence":"additional","affiliation":[{"name":"The 2nd Department of Clinical Radiology, Medical University of Warsaw, ul. Banacha 1A, 02-097 Warsaw, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dorota","family":"Piotrowska-Kownacka","sequence":"additional","affiliation":[{"name":"The 1st Department of Radiology, Medical University of Warsaw, ul. \u017bwirki i Wigury 61, 02-091 Warsaw, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3215-5085","authenticated-orcid":false,"given":"El\u017cbieta Katarzyna","family":"Biernacka","sequence":"additional","affiliation":[{"name":"The Cardinal Stefan Wyszy\u0144ski National Institute of Cardiology, ul. Alpejska 42, 04-628 Warszawa, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,1,28]]},"reference":[{"key":"ref_1","unstructured":"Finn, A. (2018, April 02). When 26.2 Miles Just Isn\u2019t Enough\u2014The Phenomenal Rise of the Ultramarathon. 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