{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,9,11]],"date-time":"2025-09-11T21:59:37Z","timestamp":1757627977575,"version":"3.44.0"},"reference-count":47,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2025,9,10]],"date-time":"2025-09-10T00:00:00Z","timestamp":1757462400000},"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><jats:title>Objective<\/jats:title><jats:p>This study aimed to investigate the dynamic relationship between chest temperature entropy, physiological load indicators, and excess post-exercise oxygen consumption (EPOC) during incremental cycling exercise using high-sampling-rate infrared thermography (IRT).<\/jats:p><\/jats:sec><jats:sec><jats:title>Methods<\/jats:title><jats:p>Twenty-four healthy young male participants (23.7 \u00b1 3.3 years; 178.6 \u00b1 9.8 cm; 78.5 \u00b1 6.4 kg; 237.8 \u00b1 48.7 min\/week training duration; maximal oxygen uptake 44.06 \u00b1 5.9 ml\/kg\/min; maximal power output 263.8 \u00b1 27.4 W) performed an incremental cycling test starting at 60 W with workload increases of 30 W every 2 minutes until exhaustion. Chest thermography, oxygen consumption (VO\u2082), blood lactate, and external load were simultaneously measured, and entropy was used to quantify the spatial complexity of temperature distribution.<\/jats:p><\/jats:sec><jats:sec><jats:title>Results<\/jats:title><jats:p>Significant non-linear positive correlations were found between standardized entropy increase and VO\u2082 (<jats:italic>R<\/jats:italic>\u00b2 = 0.809), blood lactate (<jats:italic>R<\/jats:italic>\u00b2 = 0.719), and external load (<jats:italic>R<\/jats:italic>\u00b2 = 0.841), while individual-level analyses confirmed strong associations with VO\u2082 (r = 0.874\u20130.977), lactate (r = 0.692\u20130.989), and external load (r = 0.889\u20130.986) (all p &amp;lt; 0.05). Hierarchical clustering identified three clusters corresponding to low, moderate, and high metabolic load states. During recovery, entropy was significantly associated with EPOC (<jats:italic>R<\/jats:italic>\u00b2 = 0.151), though substantial inter-individual variation was observed (r = \u20130.288 to 0.907).<\/jats:p><\/jats:sec><jats:sec><jats:title>Conclusion<\/jats:title><jats:p>Chest temperature entropy dynamically reflects exercise-induced metabolic changes and partially explains recovery processes, highlighting its potential as a novel, non-invasive marker for monitoring exercise load and recovery.<\/jats:p><\/jats:sec>","DOI":"10.3389\/fphys.2025.1631729","type":"journal-article","created":{"date-parts":[[2025,9,10]],"date-time":"2025-09-10T05:27:26Z","timestamp":1757482046000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Dynamic correlation between chest temperature entropy and physiological load indicators, and excess post-exercise oxygen consumption during incremental cycling exercise"],"prefix":"10.3389","volume":"16","author":[{"given":"Songzi","family":"Cui","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ning","family":"Du","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhongqian","family":"Liu","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chenxi","family":"Hu","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1965","published-online":{"date-parts":[[2025,9,10]]},"reference":[{"key":"B1","first-page":"186","article-title":"Thermographic evaluation of lactate level in capillary blood during post-exercise recovery","volume":"2014","author":"Adamczyk","year":"2014","journal-title":"Kinesiology"},{"key":"B2","doi-asserted-by":"publisher","first-page":"89","DOI":"10.1134\/S0362119710040109","article-title":"Human temperature portrait and its relations with aerobic working capacity and the level of blood lactate","volume":"36","author":"Akimov","year":"2010","journal-title":"Fiziol. 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