{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,19]],"date-time":"2025-11-19T19:27:40Z","timestamp":1763580460452,"version":"build-2065373602"},"reference-count":42,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2025,3,12]],"date-time":"2025-03-12T00:00:00Z","timestamp":1741737600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Research Center in Physical Activity, Health, and Leisure\u2014CIAFEL, Faculty of Sport University of Porto","award":["UIDB\/00617\/2020","LA\/P\/OO64\/2020"],"award-info":[{"award-number":["UIDB\/00617\/2020","LA\/P\/OO64\/2020"]}]},{"name":"Portuguese Foundation for Science and Technology","award":["UIDB\/00617\/2020","LA\/P\/OO64\/2020"],"award-info":[{"award-number":["UIDB\/00617\/2020","LA\/P\/OO64\/2020"]}]},{"name":"Integrative and Translational Research in Population Health (ITR), Porto, Portugal","award":["UIDB\/00617\/2020","LA\/P\/OO64\/2020"],"award-info":[{"award-number":["UIDB\/00617\/2020","LA\/P\/OO64\/2020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sports"],"abstract":"<jats:p>Background: The effective monitoring of athletes\u2019 adaptation is crucial to optimize the outcomes of altitude camps and minimize the risk of maladaptation to the hypoxic stress and intensive training. This case report assessed the hematological adaptations in 22 world-class female water polo players during a 16-day \u2018live high-train high\u2019 (LHTH) altitude camp (2320 m) and evaluated the differences between selected (n = 13) and non-selected (n = 9) players and between playing positions. Methods: Hematological parameters, including total hemoglobin mass (tHBmass) and blood volume, were measured before and after the camp. Resting heart rate, peripheral oxygen saturation, body mass, fatigue, and sleep were monitored daily. Results: Relative tHbmass increased PRE to POST (5.4 \u00b1 5.1%, range \u22123.9\u201320.2), but blood volume did not change (p = 0.797). Erythrocyte count, hemoglobin concentration, hematocrit, and red cell distribution width increased PRE\u2013POST (p &lt; 0.001, ES = 1.21\u20132.69), while mean corpuscular volume and hemoglobin decreased (p &lt; 0.001, ES = 0.51 and 0.72, respectively). No substantial differences were observed in the hematological parameters between selected and non-selected players. There was a large difference in the change in relative blood volume between centers (n = 4, PRE 74.1 \u00b1 5.4, POST 69.7 \u00b1 5.9 mL\/kg; mean \u00b1 SD) and field players (n = 15, PRE 80.8 \u00b1 10.6, POST 82.8 \u00b1 6.8 mL\/kg; adj p = 0.046, ES = 1.15) and between centers and goalkeepers (n = 3, PRE 89.7 \u00b1 9.6, POST 82.0 \u00b1 7.1 mL\/kg; adj p = 0.046, ES = 1.62). Conclusions: A 16-day LHTH camp can induce favorable hematological adaptations in world-class women\u2019s water polo players, without substantial differences between selected and non-selected players, and larger increases in field players.<\/jats:p>","DOI":"10.3390\/sports13030086","type":"journal-article","created":{"date-parts":[[2025,3,12]],"date-time":"2025-03-12T04:55:44Z","timestamp":1741755344000},"page":"86","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Hematological Adaptations to Altitude Training in Female Water Polo Players: A Case Report of a World Championships Medal-Winning Team"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8143-9132","authenticated-orcid":false,"given":"I\u00f1igo","family":"Mujika","sequence":"first","affiliation":[{"name":"Department of Physiology, Faculty of Medicine and Nursing, University of the Basque Country, 48940 Leioa, Spain"},{"name":"Exercise Science Laboratory, School of Kinesiology, Faculty of Medicine, Universidad Finis Terrae, Santiago 7501014, Chile"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2091-2608","authenticated-orcid":false,"given":"Jocelyn","family":"Mara","sequence":"additional","affiliation":[{"name":"Research Institute for Sport and Exercise, University of Canberra, Canberra, ACT 2617, Australia"}]},{"given":"Irina","family":"Zelenkova","sequence":"additional","affiliation":[{"name":"Growth, Exercise, Nutrition and Development (GENUD) Research Group, Faculty of Health and Sport Sciences, University of Zaragoza, 50009 Zaragoza, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0494-0000","authenticated-orcid":false,"given":"Rodrigo","family":"Zacca","sequence":"additional","affiliation":[{"name":"Research Center in Physical Activity, Health and Leisure (CIAFEL), Faculty of Sports, University of Porto (FADEUP), 4200-450 Porto, Portugal"},{"name":"Laboratory for Integrative and Translational Research in Population Health (ITR), 4050-600 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1555-5079","authenticated-orcid":false,"given":"David B.","family":"Pyne","sequence":"additional","affiliation":[{"name":"Research Institute for Sport and Exercise, University of Canberra, Canberra, ACT 2617, Australia"}]}],"member":"1968","published-online":{"date-parts":[[2025,3,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"11","DOI":"10.1111\/j.1600-0838.2008.00828.x","article-title":"Classical altitude training","volume":"18","year":"2008","journal-title":"Scand. 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