{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,31]],"date-time":"2026-08-31T06:18:36Z","timestamp":1788157116675,"version":"build-2803163510"},"reference-count":50,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T00:00:00Z","timestamp":1787788800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100007757","name":"Agencia Canaria De Investigaci\u00f3n Innovaci\u00f3n y Sociedad De La Informaci\u00f3n","doi-asserted-by":"publisher","award":["ProID2024010002 (SKINCAL)"],"award-info":[{"award-number":["ProID2024010002 (SKINCAL)"]}],"id":[{"id":"10.13039\/501100007757","id-type":"DOI","asserted-by":"publisher"}]},{"award":["ProID2024010002 (SKINCAL)"],"award-info":[{"award-number":["ProID2024010002 (SKINCAL)"]}],"id":[{"id":"https:\/\/ror.org\/01eeqch44","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Spanish Ministry of Science, Innovation and Universities","award":["PDC2025-165723-I00 (ISCHENIRS)"],"award-info":[{"award-number":["PDC2025-165723-I00 (ISCHENIRS)"]}]},{"award":["PDC2025-165723-I00 (ISCHENIRS)"],"award-info":[{"award-number":["PDC2025-165723-I00 (ISCHENIRS)"]}],"id":[{"id":"https:\/\/ror.org\/05r0vyz12","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biosensors"],"abstract":"<jats:p>In this study, we examined the thermal response of the vastus lateralis muscle using a skin calorimeter designed for localized measurements. Five healthy young male participants (20\u201323 years old) performed an incremental test on a cycle ergometer at 20 W\u00b7min\u22121 until exhaustion. The calorimeter\u2019s thermostat was maintained at 30 \u00b0C. Ambient temperature was 23 \u00b1 1 \u00b0C, and relative humidity ranged from 55% to 60%. The measured heat flow was modeled using functions relating mechanical power output to the thermal response. The model included the exercise phase, recovery, and sweat evaporation. The proposed model accurately reproduced the experimental data and supported a physiological interpretation of the main thermal effects. Two major contributions were identified and physiologically interpreted as muscle warming due to increased metabolic activity and a cooling effect likely linked to changes in blood perfusion. For an area of 2 \u00d7 2 cm2 and an incremental exercise of 20 W\u00b7min\u22121, the following values were obtained: (1) a resting heat loss of 150 \u00b1 20 mW; (2) an exponential increase due to exercise of 0.4 \u00b1 0.1 mW\u00b7W\u22121, with a time constant of 1.0 \u00b1 0.3 min; and (3) a negative blood-flow contribution described by a function that, in the steady state, has an amplitude of \u221220 \u00b1 9 mW. Since only five participants were included, correlations with anthropometric variables were treated as exploratory consistency checks. These results demonstrate the usefulness of the calorimeter for decomposing and quantifying muscle thermal dynamics during exercise.<\/jats:p>","DOI":"10.3390\/bios16090471","type":"journal-article","created":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T12:03:43Z","timestamp":1787832223000},"page":"471","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Skin Calorimetry of the Vastus Lateralis During Incremental Exercise: Thermal Analysis and Modeling"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6343-6683","authenticated-orcid":false,"given":"Pedro Jes\u00fas","family":"Rodr\u00edguez de Rivera","sequence":"first","affiliation":[{"name":"Department of Physics, Universidad de Las Palmas de Gran Canaria (ULPGC), 35017 Las Palmas de Gran Canaria, Spain"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"software","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"visualization","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-1724-0789","authenticated-orcid":false,"given":"Miriam","family":"Rodr\u00edguez de Rivera","sequence":"additional","affiliation":[{"name":"Cardiology Service, Hospital Universitario Marqu\u00e9s de Valdecilla, 39008 Santander, Spain"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"software","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4890-5947","authenticated-orcid":false,"given":"Fabiola","family":"Socorro","sequence":"additional","affiliation":[{"name":"Department of Physics, Universidad de Las Palmas de Gran Canaria (ULPGC), 35017 Las Palmas de Gran Canaria, Spain"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"software","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0872-9889","authenticated-orcid":false,"given":"Eduardo","family":"Garcia-Gonzalez","sequence":"additional","affiliation":[{"name":"Department of Physical Education and Research Institute of Biomedical and Health Sciences (IUIBS), University of Las Palmas de Gran Canaria, 35016 Las Palmas de Gran Canaria, Spain"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-5745-4161","authenticated-orcid":false,"given":"Elisabetta","family":"De Nigris","sequence":"additional","affiliation":[{"name":"Department of Physical Education and Research Institute of Biomedical and Health Sciences (IUIBS), University of Las Palmas de Gran Canaria, 35016 Las Palmas de Gran Canaria, Spain"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"methodology","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9215-6234","authenticated-orcid":false,"given":"Jose A. L.","family":"Calbet","sequence":"additional","affiliation":[{"name":"Department of Physical Education and Research Institute of Biomedical and Health Sciences (IUIBS), University of Las Palmas de Gran Canaria, 35016 Las Palmas de Gran Canaria, Spain"},{"name":"School of Kinesiology, Faculty of Education, The University of British Columbia, Vancouver, BC V6T 1Z1, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6737-4096","authenticated-orcid":false,"given":"Manuel","family":"Rodr\u00edguez de Rivera","sequence":"additional","affiliation":[{"name":"Department of Physics, Universidad de Las Palmas de Gran Canaria (ULPGC), 35017 Las Palmas de Gran Canaria, Spain"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"software","vocabulary":"credit"},{"role":"funding-acquisition","vocabulary":"credit"},{"role":"project-administration","vocabulary":"credit"},{"role":"resources","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Wissler, E.H. 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