{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T02:48:25Z","timestamp":1787021305368,"version":"build-2736575974"},"reference-count":52,"publisher":"The Company of Biologists","license":[{"start":{"date-parts":[[2020,1,1]],"date-time":"2020-01-01T00:00:00Z","timestamp":1577836800000},"content-version":"am","delay-in-days":0,"URL":"http:\/\/www.biologists.com\/user-licence-1-1\/"}],"funder":[{"DOI":"10.13039\/100000006","name":"Office of Naval Research","doi-asserted-by":"publisher","award":["N000141010514"],"award-info":[{"award-number":["N000141010514"]}],"id":[{"id":"10.13039\/100000006","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000001","name":"National Science Foundation","doi-asserted-by":"publisher","award":["1159123"],"award-info":[{"award-number":["1159123"]}],"id":[{"id":"10.13039\/100000001","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"abstract":"<jats:p>The dive response, bradycardia (decreased heart rate) and peripheral vasoconstriction, is the key mechanism allowing breath-hold divers to perform long-duration dives while actively swimming and hunting prey. This response is variable and modulated by factors such as dive duration, depth, exercise and cognitive control. This study assesses the potential role of exercise and relative lung volume in the regulation of heart rate (fH) during dives of adult female California sea lions instrumented with ECG, depth, and 3-axis acceleration data loggers. A positive relationship between activity (minimum specific acceleration) and fH throughout dives suggested increased muscle perfusion associated with exercise. However, apart from late ascent, fH during dives was still less than or equal to resting heart rate (on land). In addition, the activity-fH relationship was weaker in long, deep dives consistent with prioritization of blood oxygen conservation over blood oxygen delivery to muscle in those dives. Pulmonary stretch receptor reflexes may also contribute to fH regulation as fH profiles generally paralleled changes in relative lung volume, especially in shallower dives and during early descent and late ascent of deeper dives. Overall, these findings support the concept that both exercise and pulmonary stretch receptor reflexes may influence the dive response in sea lions.<\/jats:p>","DOI":"10.1242\/jeb.214163","type":"journal-article","created":{"date-parts":[[2020,2,25]],"date-time":"2020-02-25T15:19:22Z","timestamp":1582643962000},"source":"Crossref","is-referenced-by-count":9,"title":["Stroke effort and relative lung volume influence heart rate in diving sea lions"],"prefix":"10.1242","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5028-066X","authenticated-orcid":false,"given":"Birgitte I.","family":"McDonald","sequence":"first","affiliation":[{"name":"Moss Landing Marine Laboratories, San Jose State University. 8272 Moss Landing Rd, Moss Landing, CA 95039, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0563-0509","authenticated-orcid":false,"given":"Michael S.","family":"Tift","sequence":"additional","affiliation":[{"name":"Department of Biology and Marine Biology, University of North Carolina Wilmington, 601 S. College Rd., Wilmington, NC 28403, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Luis A.","family":"H\u00fcckst\u00e4dt","sequence":"additional","affiliation":[{"name":"Institute of Marine Sciences, University of California Santa Cruz. 115 McAllister Way, Santa Cruz CA, 95060, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8789-2627","authenticated-orcid":false,"given":"Michael","family":"Jeffko","sequence":"additional","affiliation":[{"name":"United States Coast Guard Academy, 27 Mohegan Way, New London, CT, 06320 USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1556-770X","authenticated-orcid":false,"given":"Paul J.","family":"Ponganis","sequence":"additional","affiliation":[{"name":"Scripps Institution of Oceanography - University of California San Diego. 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