{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,2]],"date-time":"2026-09-02T22:05:09Z","timestamp":1788386709104,"version":"build-2803163510"},"reference-count":35,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,7,8]],"date-time":"2026-07-08T00:00:00Z","timestamp":1783468800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Physiol."],"abstract":"\n Background<\/jats:title>\n During Ski mountaineering (SkiMo), athletes are exposed to multiple environmental stressors, notably cold temperatures and reduced oxygen availability. However, how athletes thermoregulate under such conditions remains unknown.<\/jats:p>\n <\/jats:sec>\n \n Methods<\/jats:title>\n \n This observational study investigated the thermal response of elite SkiMo athletes exercising under cold\/windy conditions at altitude. Core (T\n core<\/jats:sub>\n ) and skin (T\n skin<\/jats:sub>\n ) temperature were continuously recorded in 11 elite and 2 national SkiMo athletes (10 males, 3 females) during simulated races performed at an altitude of 2600m above sea level using ingestible electronic pills and T\n skin<\/jats:sub>\n sensors placed on the chest, arm, thigh, shin and hand, respectively. Each athlete completed four 15-minute uphill skiing runs at 85-90% HR\n max<\/jats:sub>\n , each separated by a 2-3-minute downhill ski back to the starting position. Heart rate and speed were continuously recorded. Ambient temperature ranged from -8.3\u00a0\u00b0C to 1.3\u00a0\u00b0C, with wind chill temperatures reaching -11\u00a0\u00b0C.\n <\/jats:p>\n <\/jats:sec>\n \n Results<\/jats:title>\n \n T\n core<\/jats:sub>\n significantly increased from baseline (37.4\u00a0\u00b1\u00a00.2\u00a0\u00b0C) to warm-up (38.2\u00a0\u00b1\u00a00.2\u00a0\u00b0C, p \u2264 0.001). Thereafter, 46% of athletes maintained their T\n core<\/jats:sub>\n (+0.2\u00a0\u00b1\u00a00.3\u00a0\u00b0C, p=0.225), with a peak of 39.4\u00a0\u00b0C in one athlete, while the remaining 54% showed a decrease of 0.8\u00a0\u00b1\u00a00.5\u00a0\u00b0C (p=0.003; minimum 36.5\u00a0\u00b0C). T\n skin<\/jats:sub>\n largely decreased on all locations (all p&lt;0.001), reaching lowest mean temperatures on the hand (21.2\u00a0\u00b1\u00a02.5\u00a0\u00b0C) and thigh (22.3\u00a0\u00b1\u00a02.7\u00a0\u00b0C). Changes in T\n core<\/jats:sub>\n and T\n skin<\/jats:sub>\n were not related to uphill speed.\n <\/jats:p>\n <\/jats:sec>\n \n Conclusion<\/jats:title>\n \n SkiMo performed under cold and hypoxic conditions clearly lowers T\n skin<\/jats:sub>\n of elite athletes, especially at the extremities. Contrarily, we observed a high inter-individual variability in T\n core<\/jats:sub>\n responses, showing that half of athletes were unable to maintain their T\n core<\/jats:sub>\n despite high exercise intensities, whereas the other half increased their temperatures. The observation that some athletes increased whereas others decreased their T\n core<\/jats:sub>\n suggests differences in net heat balance, with some having a positive heat balance (heat gain) and others a negative heat balance (heat loss).\n <\/jats:p>\n <\/jats:sec>","DOI":"10.3389\/fphys.2026.1831717","type":"journal-article","created":{"date-parts":[[2026,7,8]],"date-time":"2026-07-08T04:51:41Z","timestamp":1783486301000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":2,"title":["Thermoregulatory responses of elite ski mountaineers during simulated races under cold, hypoxic conditions"],"prefix":"10.3389","volume":"17","author":[{"given":"Tobias","family":"D\u00fcnnwald","sequence":"first","affiliation":[{"name":"Institute for Sports Medicine, Alpine Medicine & Health Tourism (ISAG), Private University for Health Sciences and Health Technology, UMIT Tirol","place":["Hall in Tirol, Austria"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wolfgang","family":"Schobersberger","sequence":"additional","affiliation":[{"name":"Institute for Sports Medicine, Alpine Medicine & Health Tourism (ISAG), Private University for Health Sciences and Health Technology, UMIT Tirol","place":["Hall in Tirol, Austria"]},{"name":"Tirol Kliniken GmbH Innsbruck","place":["Innsbruck, Austria"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anika","family":"K\u00f6ck","sequence":"additional","affiliation":[{"name":"Institute for Sports Medicine, Alpine Medicine & Health Tourism (ISAG), Private University for Health Sciences and Health Technology, UMIT Tirol","place":["Hall in Tirol, Austria"]},{"name":"Tirol Kliniken GmbH Innsbruck","place":["Innsbruck, Austria"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yannis","family":"Pitsiladis","sequence":"additional","affiliation":[{"name":"Department of Biology, Hong Kong Baptist University","place":["Hong Kong, Hong Kong SAR, China"]},{"name":"Centre for Exercise Science and Medicine (CESAME), Hong Kong Baptist University","place":["Hong Kong, Hong Kong SAR, China"]},{"name":"Human Telemetrics LTD","place":["London, United Kingdom"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Panagiotis","family":"Verdoukas","sequence":"additional","affiliation":[{"name":"Human Telemetrics LTD","place":["London, United Kingdom"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hanns-Christian","family":"Gunga","sequence":"additional","affiliation":[{"name":"Institute of Physiology, Center for Space Medicine and Extreme Environments Berlin, Charit\u00e9 \u2013Universit\u00e4tsmedizin Berlin","place":["Berlin, Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sebastien","family":"Racinais","sequence":"additional","affiliation":[{"name":"CREPS Montpellier - Font-Romeu, Environmental Stress Unit","place":["Montpellier, France"]},{"name":"DMEM, University of Montpellier, INRAE","place":["Montpellier, France"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,7,8]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"400","DOI":"10.1080\/17461391.2020.1754470","article-title":"Thermoregulation and shivering responses in elite alpine skiers","volume":"21","author":"Alhammoud","year":"2021","journal-title":"Eur. 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