{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,11]],"date-time":"2026-05-11T11:19:05Z","timestamp":1778498345190,"version":"3.51.4"},"reference-count":8,"publisher":"SAGE Publications","issue":"2","license":[{"start":{"date-parts":[[2025,11,17]],"date-time":"2025-11-17T00:00:00Z","timestamp":1763337600000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/journals.sagepub.com\/page\/policies\/text-and-data-mining-license"}],"content-domain":{"domain":["journals.sagepub.com"],"crossmark-restriction":true},"short-container-title":["High Altitude Medicine &amp; Biology"],"published-print":{"date-parts":[[2026,6,1]]},"abstract":"<jats:p>\n                    \u00c1lvarez-Herms, Jes\u00fas, Kilian Jornet, Martin Burtscher, Adriana Gonz\u00e1lez, and Adri\u00e1n Odriozola. Gut microbiota dynamics during extreme altitude climbing: a longitudinal case report.\n                    <jats:italic toggle=\"yes\">High Alt Med Biol.<\/jats:italic>\n                    27:123\u2013127, 2026.\u2014The present case study would explore the acute changes of gut microbiota (GM) and some physiological responses of a world-class mountaineer during a 4-week stay at altitudes between 3,600 and 4,200 m, with four rapid ascents to different extreme altitudes, that is, 6,700, 7,000, 8,000, and 8,400 m. Severe hypoxemia, hyperglycemia, ketoacidosis, and sympathetic dominance were found to be proportionally higher with increasing altitude. Thus, the GM changed during the acclimatization period, decreasing bacterial diversity (Shannon index from 5.88 to 4.56). Remarkably, during the third week, a transient increase of the pathogenic bacteria\n                    <jats:italic toggle=\"yes\">Ruminococcus gnavus<\/jats:italic>\n                    (+2,800%) was found. Thus, this significant elevation coincided with the impaired systemic health and gastrointestinal and respiratory complications. In conclusion, the present exploratory study found that a favorable and healthy GM profile, characterized by elevated mucolytic and short-chain fatty acids-producing bacteria, may improve hypoxic tolerance, reduce the risk of developing gut leakage syndrome and systemic endotoxemia, and protect against acute mountain sickness.\n                  <\/jats:p>","DOI":"10.1177\/15578682251396447","type":"journal-article","created":{"date-parts":[[2025,11,18]],"date-time":"2025-11-18T05:04:01Z","timestamp":1763442241000},"page":"123-127","update-policy":"https:\/\/doi.org\/10.1177\/sage-journals-update-policy","source":"Crossref","is-referenced-by-count":1,"title":["Gut Microbiota Dynamics During Extreme Altitude Climbing: A Longitudinal Case Report"],"prefix":"10.1177","volume":"27","author":[{"given":"Jes\u00fas","family":"\u00c1lvarez-Herms","sequence":"first","affiliation":[{"name":"Phymolab, Exercise Physiology Laboratory, Collado Hermoso (Segovia), Spain."},{"name":"Departamento de Gen\u00e9tica, Antropolog\u00eda F\u00edsica y Fisiolog\u00eda Animal, Facultad de Ciencia y Tecnolog\u00eda, Universidad del Pa\u00eds Vasco, Campus de Leioa (Vizkaia), Spain."}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kilian","family":"Jornet","sequence":"additional","affiliation":[{"name":"Mountain Life, M\u00e5ndalen, Norway."}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Martin","family":"Burtscher","sequence":"additional","affiliation":[{"name":"Department of Sport Science, University of Inssbruck, Inssbruck, Austria."}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Adriana","family":"Gonz\u00e1lez","sequence":"additional","affiliation":[{"name":"Departamento de Gen\u00e9tica, Antropolog\u00eda F\u00edsica y Fisiolog\u00eda Animal, Facultad de Ciencia y Tecnolog\u00eda, Universidad del Pa\u00eds Vasco, Campus de Leioa (Vizkaia), Spain."}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Adri\u00e1n","family":"Odriozola","sequence":"additional","affiliation":[{"name":"Departamento de Gen\u00e9tica, Antropolog\u00eda F\u00edsica y Fisiolog\u00eda Animal, Facultad de Ciencia y Tecnolog\u00eda, Universidad del Pa\u00eds Vasco, Campus de Leioa (Vizkaia), Spain."}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"179","published-online":{"date-parts":[[2025,11,17]]},"reference":[{"key":"e_1_3_2_2_1","doi-asserted-by":"publisher","DOI":"10.3389\/fphys.2023.1284423"},{"key":"e_1_3_2_3_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.smhs.2023.03.003"},{"key":"e_1_3_2_4_1","doi-asserted-by":"publisher","DOI":"10.3389\/fmicb.2021.690600"},{"key":"e_1_3_2_5_1","doi-asserted-by":"publisher","DOI":"10.3389\/fmicb.2024.1371247"},{"key":"e_1_3_2_6_1","doi-asserted-by":"publisher","DOI":"10.1152\/ajpgi.00253.2018"},{"key":"e_1_3_2_7_1","doi-asserted-by":"publisher","DOI":"10.1249\/01.mss.0000174888.22930.e0"},{"key":"e_1_3_2_8_1","doi-asserted-by":"publisher","DOI":"10.3389\/fmicb.2024.1369627"},{"key":"e_1_3_2_9_1","doi-asserted-by":"publisher","DOI":"10.1152\/ajpregu.00270.2021"}],"container-title":["High Altitude Medicine &amp; Biology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/journals.sagepub.com\/doi\/pdf\/10.1177\/15578682251396447","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.sagepub.com\/doi\/full-xml\/10.1177\/15578682251396447","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.sagepub.com\/doi\/pdf\/10.1177\/15578682251396447","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,5,11]],"date-time":"2026-05-11T10:46:24Z","timestamp":1778496384000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.sagepub.com\/doi\/10.1177\/15578682251396447"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,11,17]]},"references-count":8,"journal-issue":{"issue":"2","published-print":{"date-parts":[[2026,6,1]]}},"alternative-id":["10.1177\/15578682251396447"],"URL":"https:\/\/doi.org\/10.1177\/15578682251396447","relation":{},"ISSN":["1527-0297","1557-8682"],"issn-type":[{"value":"1527-0297","type":"print"},{"value":"1557-8682","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,11,17]]}}}