{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,20]],"date-time":"2026-08-20T19:15:43Z","timestamp":1787253343743,"version":"build-2736575974"},"reference-count":43,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2023,9,14]],"date-time":"2023-09-14T00:00:00Z","timestamp":1694649600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Research Council of Lithuania","award":["MIP-017\/2014"],"award-info":[{"award-number":["MIP-017\/2014"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Medicina"],"abstract":"<jats:p>Background and Objectives: To date, understanding age-related changes in cognitive processes during heat exposure still needs to be better-understood. Thus, the main aim of the current study was to evaluate the effects of whole-body hyperthermia (WBH), i.e., a \u2248 2.5 \u00b0C increase in rectal temperature (Tre) from overnight-fast baseline value, on cognitive functioning in old and young men and to explore factors, such as stress and thermophysiological strain, that could influence such changes. Materials and Methods: Ten young (19\u201321 years of age) and nine old (61\u201380 years of age) healthy men underwent an experimental trial with passive lower-body heating in hot water immersion (HWI) at 43 \u00b0C (HWI\u201343 \u00b0C) until Tre reached 39 \u00b0C in old adults and 39.5 \u00b0C in young adults. Cognitive performance and cortisol concentration were assessed before and after HWI, and the physiological strain index (PSI) was assessed during HWI\u201343 \u00b0C. Results: PSI was lower and cortisol concentration was greater after HWI\u201343 \u00b0C in the old group compared with the young group (p &lt; 0.05). Surprisingly, hyperthermia improved cognitive flexibility only in old adults, whereas short-term and visual recognition memories were maintained in both age groups. Conclusions: A \u2248 2.5 \u00b0C increase in rectal temperature can improve executive function in old adults, and this increase parallels the increased cortisol concentration and the lower thermophysiological strain under severe WBH conditions.<\/jats:p>","DOI":"10.3390\/medicina59091665","type":"journal-article","created":{"date-parts":[[2023,9,15]],"date-time":"2023-09-15T02:54:13Z","timestamp":1694746453000},"page":"1665","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Age-Related Difference in Cognitive Performance under Severe Whole-Body Hyperthermia Parallels Cortisol and Physical Strain Responses"],"prefix":"10.3390","volume":"59","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7863-7827","authenticated-orcid":false,"given":"Junli","family":"Wang","sequence":"first","affiliation":[{"name":"Institute of Sport Science and Innovations, Lithuanian Sports University, LT-44221 Kaunas, Lithuania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rima","family":"Solianik","sequence":"additional","affiliation":[{"name":"Institute of Sport Science and Innovations, Lithuanian Sports University, LT-44221 Kaunas, Lithuania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nerijus","family":"Eimantas","sequence":"additional","affiliation":[{"name":"Institute of Sport Science and Innovations, Lithuanian Sports University, LT-44221 Kaunas, Lithuania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Neringa","family":"Baranauskiene","sequence":"additional","affiliation":[{"name":"Institute of Sport Science and Innovations, Lithuanian Sports University, LT-44221 Kaunas, Lithuania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1369-7524","authenticated-orcid":false,"given":"Marius","family":"Brazaitis","sequence":"additional","affiliation":[{"name":"Institute of Sport Science and Innovations, Lithuanian Sports University, LT-44221 Kaunas, Lithuania"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,9,14]]},"reference":[{"key":"ref_1","unstructured":"(2023, June 28). 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