{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,24]],"date-time":"2026-01-24T17:25:09Z","timestamp":1769275509628,"version":"3.49.0"},"reference-count":58,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2023,4,20]],"date-time":"2023-04-20T00:00:00Z","timestamp":1681948800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JCM"],"abstract":"<jats:p>COVID-19 has a deteriorating impact on health which is especially important for endurance athletes (EAs) who need to maintain continuity of training. The illness affects sleep and psychology, which influence sport performance. The aims of this study were: (1) to assess the consequences of mild COVID-19 on sleep and psychology and (2) to assess the consequences of mild COVID-19 on cardiopulmonary exercise test (CPET) results. A total of 49 EAs (males = 43, 87.76%; females = 6, 12.24%; age = 39.9 \u00b1 7.8 years; height = 178.4 \u00b1 6.8 cm; weight = 76.3 \u00b1 10.4 kg; BMI = 24.0 \u00b1 2.6 kg\u00b7m\u22122) underwent a maximal cycling or running CPET pre- and post-COVID-19 and completed an original survey. Exercise performance deteriorated after COVID-19 (maximal oxygen uptake, VO2max = 47.81 \u00b1 7.81 vs. 44.97 \u00b1 7.00 mL\u00b7kg\u00b7min\u22121 pre- and post-infection, respectively; p &lt; 0.001). Waking up at night affected the heart rate (HR) at the respiratory compensation point (RCP) (p = 0.028). Sleep time influenced pulmonary ventilation (p = 0.013), breathing frequency (p = 0.010), and blood lactate concentration (Lac) (p = 0.013) at the RCP. The maximal power\/speed (p = 0.046) and HR (p = 0.070) were linked to the quality of sleep. Stress management and relaxation techniques were linked with VO2max (p = 0.046), maximal power\/speed (p = 0.033), and maximal Lac (p = 0.045). Cardiorespiratory fitness deteriorated after mild COVID-19 and was correlated with sleep and psychological indices. Medical professionals should encourage EAs to maintain proper mental health and sleep after COVID-19 infection to facilitate recovery.<\/jats:p>","DOI":"10.3390\/jcm12083002","type":"journal-article","created":{"date-parts":[[2023,4,21]],"date-time":"2023-04-21T02:05:31Z","timestamp":1682042731000},"page":"3002","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Impact of COVID-19 Infection on Cardiorespiratory Fitness, Sleep, and Psychology of Endurance Athletes\u2014CAESAR Study"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5917-8119","authenticated-orcid":false,"given":"Daniel","family":"\u015ali\u017c","sequence":"first","affiliation":[{"name":"3rd Department of Internal Medicine and Cardiology, Medical University of Warsaw, 04-749 Warsaw, Poland"},{"name":"School of Public Health, Postgraduate Medical Education Center, 01-813 Warsaw, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Szczepan","family":"Wiecha","sequence":"additional","affiliation":[{"name":"Department of Physical Education and Health, Faculty in Biala Podlaska, Jozef Pilsudski University of Physical Education in Warsaw, 21-500 Biala Podlaska, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2009-2200","authenticated-orcid":false,"given":"Jakub S.","family":"G\u0105sior","sequence":"additional","affiliation":[{"name":"Department of Pediatric Cardiology and General Pediatrics, Medical University of Warsaw, 02-091 Warsaw, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0303-6135","authenticated-orcid":false,"given":"Przemys\u0142aw Seweryn","family":"Kasiak","sequence":"additional","affiliation":[{"name":"Students\u2019 Scientific Group of Lifestyle Medicine, 3rd Department of Internal Medicine and Cardiology, Medical University of Warsaw, 04-749 Warsaw, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2941-4878","authenticated-orcid":false,"given":"Katarzyna","family":"Ulaszewska","sequence":"additional","affiliation":[{"name":"Students\u2019 Scientific Group of Lifestyle Medicine, 3rd Department of Internal Medicine and Cardiology, Medical University of Warsaw, 04-749 Warsaw, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marcin","family":"Lewandowski","sequence":"additional","affiliation":[{"name":"Department of Pharmacology and Clinical Pharmacology Collegium Medicum, Cardinal Stefan Wyszy\u0144ski University in Warsaw, 00-927 Warsaw, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7245-9724","authenticated-orcid":false,"given":"Marcin","family":"Barylski","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine and Cardiac Rehabilitation, Medical University of Lodz, 90-419 \u0141\u00f3d\u017a, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9569-1486","authenticated-orcid":false,"given":"Artur","family":"Mamcarz","sequence":"additional","affiliation":[{"name":"3rd Department of Internal Medicine and Cardiology, Medical University of Warsaw, 04-749 Warsaw, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,4,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1287","DOI":"10.1007\/s42399-020-00439-1","article-title":"The \u201cPandemic\u201d of Disinformation in COVID-19","volume":"2","author":"Tagliabue","year":"2020","journal-title":"SN Compr. 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