{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,4]],"date-time":"2026-06-04T01:29:20Z","timestamp":1780536560378,"version":"3.54.1"},"reference-count":22,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2024,1,26]],"date-time":"2024-01-26T00:00:00Z","timestamp":1706227200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/2.zoppoz.workers.dev:443\/https\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>(1) Background: It is important to monitor the body core temperature (Tc) of individuals with chronic heart failure (CHF) during rest or exercise, as they are susceptible to complications. Gastrointestinal capsules are a robust indicator of the Tc at rest and during exercise. A practical and non-invasive sensor called CALERA Research was recently introduced, promising accuracy, sensitivity, continuous real-time analysis, repeatability, and reproducibility. This study aimed to assess the validity of the CALERA Research sensor when monitoring patients with CHF during periods of rest, throughout brief cardiopulmonary exercise testing, and during their subsequent recovery. (2) Methods: Twelve male CHF patients volunteered to participate in a 70-min protocol in a laboratory at 28 \u00b0C and 39% relative humidity. After remaining calm for 20 min, they underwent a symptom-limited stress test combined with ergospirometry on a treadmill, followed by 40 min of seated recovery. The Tc was continuously monitored by both Tc devices. (3) Results: The Tc values from the CALERA Research sensor and the gastrointestinal sensor showed no associations at rest (r = 0.056, p = 0.154) and during exercise (r = \u22120.015, p = 0.829) and a weak association during recovery (r = 0.292, p &lt; 0.001). The Cohen\u2019s effect size of the differences between the two Tc assessment methods for rest, exercise, and recovery was 1.04 (large), 0.18 (none), and 0.45 (small), respectively. The 95% limit of agreement for the CALERA Research sensor was \u22120.057 \u00b1 1.03 \u00b0C. (4) Conclusions: The CALERA sensor is a practical and, potentially, promising device, but it does not provide an accurate Tc estimation in CHF patients at rest, during brief exercise testing, and during recovery.<\/jats:p>","DOI":"10.3390\/s24030807","type":"journal-article","created":{"date-parts":[[2024,1,30]],"date-time":"2024-01-30T12:06:58Z","timestamp":1706616418000},"page":"807","update-policy":"https:\/\/2.zoppoz.workers.dev:443\/https\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Validity of the CALERA Research Sensor to Assess Body Core Temperature during Maximum Exercise in Patients with Heart Failure"],"prefix":"10.3390","volume":"24","author":[{"ORCID":"https:\/\/2.zoppoz.workers.dev:443\/https\/orcid.org\/0000-0003-2610-4900","authenticated-orcid":false,"given":"Antonia","family":"Kaltsatou","sequence":"first","affiliation":[{"name":"FAME Laboratory, Department of Physical Education and Sport Science, University of Thessaly, 42100 Trikala, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maria","family":"Anifanti","sequence":"additional","affiliation":[{"name":"Sportsmedicine Laboratory, Department of Physical Education and Sport Science, Aristotle University of Thessaloniki, 57000 Thermi, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/2.zoppoz.workers.dev:443\/https\/orcid.org\/0000-0002-9823-3915","authenticated-orcid":false,"given":"Andreas D.","family":"Flouris","sequence":"additional","affiliation":[{"name":"FAME Laboratory, Department of Physical Education and Sport Science, University of Thessaly, 42100 Trikala, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Georgia","family":"Xiromerisiou","sequence":"additional","affiliation":[{"name":"Department of Neurology, University Hospital of Larissa, University of Thessaly, 41110 Larissa, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/2.zoppoz.workers.dev:443\/https\/orcid.org\/0000-0002-5023-2542","authenticated-orcid":false,"given":"Evangelia","family":"Kouidi","sequence":"additional","affiliation":[{"name":"Sportsmedicine Laboratory, Department of Physical Education and Sport Science, Aristotle University of Thessaloniki, 57000 Thermi, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,1,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"99","DOI":"10.1001\/jama.291.1.99","article-title":"Health effects of climate change","volume":"291","author":"Haines","year":"2004","journal-title":"JAMA"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"3357","DOI":"10.1038\/s41467-020-16970-7","article-title":"Increasing trends in regional heatwaves","volume":"11","author":"Lewis","year":"2020","journal-title":"Nat. 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