{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,11]],"date-time":"2026-06-11T17:58:57Z","timestamp":1781200737668,"version":"3.54.1"},"reference-count":32,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2024,9,11]],"date-time":"2024-09-11T00:00:00Z","timestamp":1726012800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Zagreb University Support","award":["101106-22-3113"],"award-info":[{"award-number":["101106-22-3113"]}]}],"content-domain":{"domain":["www.mdpi.com"],"crossmark-restriction":true},"short-container-title":["Diagnostics"],"abstract":"<jats:p>AIM: Our goal was to examine the effect of high-intensity physical activity on changes in the lipid profile, complete blood count (CBC), iron metabolism, and kidney and liver function tests of professional water polo players. METHODS: This study included twenty professional male water polo players. Blood sampling was carried out at the beginning of the season and during periods of high-intensity training. CBCs were determined with a Siemens Advia 2120i hematology analyzer. A Beckman CoulterAU680 chemistry analyzer was used to determine the serum concentrations\/activities of lipid profiles and liver and kidney function test analytes. The lipid athlete scores were also determined. RESULTS: The mean corpuscular volume (p = 0.006), platelet count (p = 0.008), and mean platelet volume (p &lt; 0.001) significantly decreased during the high-intensity period, compared with the beginning of the season. The total iron-binding capacity increased (p = 0.001), and ferritin concentrations significantly declined (p = 0.017). The lipid profiles revealed a significant difference between phases, with slight increases in serum total (p = 0.025) and LDL cholesterol (p = 0.002) levels and a decrease in triglyceride concentrations (p = 0.040) in the high-intensity period. During the high-intensity period, the liver and kidney function tests showed a substantial positive effect on lactate dehydrogenase levels (p &lt; 0.001), aspartate aminotransferase (p = 0.028) serum activity, and total protein concentrations (p = 0.033), compared with the beginning of the season. CONCLUSIONS: Water polo players might exhibit a decrease in some CBC parameters, an increase in LDL cholesterol, and a decrease in liver function biomarkers due to intense training at the peak of the competitive season. Kidney function biomarkers remain unchanged.<\/jats:p>","DOI":"10.3390\/diagnostics14182014","type":"journal-article","created":{"date-parts":[[2024,9,12]],"date-time":"2024-09-12T02:30:23Z","timestamp":1726108223000},"page":"2014","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Effects of High-Intensity Training on Complete Blood Count, Iron Metabolism, Lipid Profile, Liver, and Kidney Function Tests of Professional Water Polo Players"],"prefix":"10.3390","volume":"14","author":[{"given":"Frane","family":"Bukvi\u0107","sequence":"first","affiliation":[{"name":"Department of Orthopedics and Trauma Surgery, University Hospital \u2018Sveti Duh\u2019, 10000 Zagreb, Croatia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1735-1865","authenticated-orcid":false,"given":"Domagoj","family":"Marijan\u010devi\u0107","sequence":"additional","affiliation":[{"name":"Department of Clinical Chemistry, University Hospital Centre \u2018Sestre Milosrdnice\u2019, 10000 Zagreb, Croatia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Helena","family":"\u010ci\u010dak","sequence":"additional","affiliation":[{"name":"Department of Medical Laboratory Diagnostics, University Hospital \u2018Sveti Duh\u2019, 10000 Zagreb, Croatia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2391-5241","authenticated-orcid":false,"given":"Ana-Maria","family":"\u0160imundi\u0107","sequence":"additional","affiliation":[{"name":"Unit for Preanalytics, Department of Global Medical & Clinical Affairs, Business Greiner Bio-One GmbH, 4550 Kremsm\u00fcnster, Austria"},{"name":"Faculty of Pharmacy and Medical Biochemistry, Zagreb University, 10000 Zagreb, Croatia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5741-6168","authenticated-orcid":false,"given":"Daria","family":"Pa\u0161ali\u0107","sequence":"additional","affiliation":[{"name":"Department of Medical Chemistry, Biochemistry and Clinical Chemistry, University of Zagreb School of Medicine, 10000 Zagreb, Croatia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lora","family":"Duki\u0107","sequence":"additional","affiliation":[{"name":"Clinical Department of Laboratory Diagnostics, Clinical Hospital Center Rijeka, 51000 Rijeka, Croatia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,9,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"i3857","DOI":"10.1136\/bmj.i3857","article-title":"Physical Activity and Risk of Breast Cancer, Colon Cancer, Diabetes, Ischemic Heart Disease, and Ischemic Stroke Events: Systematic Review and Dose-Response Meta-Analysis for the Global Burden of Disease Study 2013","volume":"354","author":"Kyu","year":"2016","journal-title":"BMJ"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Eime, R., Harvey, J., Charity, M., Casey, M., van Uffelen, J., and Payne, W. 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