{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,5]],"date-time":"2026-08-05T05:44:57Z","timestamp":1785908697694,"version":"3.56.0"},"reference-count":50,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,8,5]],"date-time":"2026-08-05T00:00:00Z","timestamp":1785888000000},"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":"<jats:sec>\n                    <jats:title>Introduction<\/jats:title>\n                    <jats:p>Hot-dry (HD) and warm-humid (WH) environments with equivalent wet-bulb globe temperature (WBGT) may be expected to produce similar physiological strain; however, previous studies have reported divergent thermoregulatory and cardiovascular responses. This study compared heat storage, thermal, and cardiovascular responses between HD and WH conditions with matched WBGT during cycling.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>\n                      Ten healthy, active, non-heat-acclimatized males completed two randomized crossover trials consisting of 60 minutes of cycling at an individualized workload corresponding to 55% of peak power output in HD (39.2\u00b0C, 30% relative humidity [RH]) and WH (34.2\u00b0C, 55% RH) conditions with equivalent WBGT (~30\u00b0C). Heat storage, dry heat loss (DHL), and evaporative heat loss (EHL) were estimated using partitional calorimetry. Rectal temperature (T\n                      <jats:sub>re<\/jats:sub>\n                      ), mean skin temperature (T\n                      <jats:sub>sk<\/jats:sub>\n                      ), and cardiovascular responses were measured throughout the trials.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>No condition differences were observed for cumulative heat storage, Tre, heart rate, blood pressure, or forearm skin blood flux (all p &amp;gt; .050). Tsk (HD: 36.28 \u00b1 0.67\u00b0C, WH: 35.89 \u00b1 0.70\u00b0C; p = .030, \u03b7p\u00b2 = .465) and EHL (HD: 450 \u00b1 53 W, WH: 319 \u00b1 30 W; p &amp;lt; .001, \u03b7p\u00b2 = .932) were greater in HD, whereas DHL was greater in WH (HD: \u221280 \u00b1 25 W; WH: 48 \u00b1 25 W; p &amp;lt; .001, \u03b7p\u00b2 = .950). Conclusion: Despite similar heat storage and cardiovascular strain, matched-WBGT environments altered the mechanisms of heat exchange. Thus, ambient temperature, humidity, and workload should be considered alongside WBGT when monitoring heat strain and selecting heat-mitigation strategies.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Despite similar heat storage and cardiovascular strain, matched-WBGT environments altered the mechanisms of heat exchange. Thus, ambient temperature, humidity, and workload should be considered alongside WBGT when monitoring heat strain and selecting heat-mitigation strategies.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fphys.2026.1856143","type":"journal-article","created":{"date-parts":[[2026,8,5]],"date-time":"2026-08-05T04:51:59Z","timestamp":1785905519000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Thermoregulation in hot-dry and warm-humid heat stress during cycling among males"],"prefix":"10.3389","volume":"17","author":[{"given":"Xiujing","family":"Zhao","sequence":"first","affiliation":[{"name":"Heat & Hydration Optimization (H2O) Lab , University of Arkansas","place":["Fayetteville, AR, United States"]},{"name":"Exercise Science Research Center, University of Arkansas","place":["Fayetteville, AR, United States"]},{"name":"Department of Health, Human Performance & Recreation, University of Arkansas","place":["Fayetteville, AR, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Brendon P.","family":"McDermott","sequence":"additional","affiliation":[{"name":"Heat & Hydration Optimization (H2O) Lab , University of Arkansas","place":["Fayetteville, AR, United States"]},{"name":"Exercise Science Research Center, University of Arkansas","place":["Fayetteville, AR, United States"]},{"name":"Department of Health, Human Performance & Recreation, University of Arkansas","place":["Fayetteville, AR, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cory L.","family":"Butts","sequence":"additional","affiliation":[{"name":"Department of Health, Human Performance & Recreation, University of Arkansas","place":["Fayetteville, AR, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,8,5]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"480","DOI":"10.1007\/BF00422956","article-title":"Efficiency of sweat evaporation in unacclimatized man working in a hot humid environment","volume":"54","author":"Alber-Wallerstr\u00f6m","year":"1985","journal-title":"Eur. 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