{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,4]],"date-time":"2026-05-04T09:39:44Z","timestamp":1777887584743,"version":"3.51.4"},"reference-count":35,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,5,1]],"date-time":"2026-05-01T00:00:00Z","timestamp":1777593600000},"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>Background<\/jats:title>\n                    <jats:p>Left bundle branch block (LBBB) is a heart rate (HR)\u2013dependent cardiac conduction disorder that may occur in the absence of structural heart disease and can be associated with painful episodes. Evidence supporting exercise-based interventions in this setting is limited. We report the case of a 41-year-old woman with paroxysmal, painful LBBB, with onset occurring marginally above resting HR.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>\n                      After a diagnostic evaluation demonstrating preserved biventricular function, absence of myocardial ischemia, and normal hemodynamic responses, a 10-month supervised training program was implemented in three sequential phases: (1) diaphragmatic breathing exercise; (2) aerobic exercise performed below the individual LBBB HR threshold; (3) interval and steady-state aerobic exercise prescribed according to individually determined ventilatory thresholds (VT1 and VT2). Resting HR, HR at LBBB onset, maximal oxygen consumption (V\u02d9O\n                      <jats:sub>2<\/jats:sub>\n                      max), ventilatory thresholds, and their associated HRs were longitudinally assessed.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      After training, resting HR decreased by 15 bpm, while HR at LBBB onset increased by 50 bpm, markedly expanding the safe exertional window. V\u02d9O\n                      <jats:sub>2<\/jats:sub>\n                      max improved progressively, together with upward shifts in VT1 and VT2, and reductions in corresponding HRs. Importantly, the patient reported resolution of LBBB-related pain during daily activities and even when LBBB was occasionally elicited at higher exercise intensities.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>This case suggests that a tailored respiratory and aerobic training program may safely improve cardiovascular efficiency, functional capacity, and symptom control in a patient with painful, HR-dependent LBBB. Individualized exercise training may represent a non-invasive adjunct or alternative to pharmacological or pacing strategies in selected patients.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fphys.2026.1793253","type":"journal-article","created":{"date-parts":[[2026,5,1]],"date-time":"2026-05-01T04:18:01Z","timestamp":1777609081000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Case Report: Integrated cardiovascular and respiratory training as a novel therapeutic approach in a case of painful left bundle branch block"],"prefix":"10.3389","volume":"17","author":[{"given":"Oscar","family":"Crisafulli","sequence":"first","affiliation":[{"name":"Centtro di Ricerca Interdipartimentale Attivit\u00e0 Motorie e Sportive (CRIAMS)-Sport Medicine Centre Voghera, University of Pavia","place":["Voghera, Italy"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Venere","family":"Quintiero","sequence":"additional","affiliation":[{"name":"Centtro di Ricerca Interdipartimentale Attivit\u00e0 Motorie e Sportive (CRIAMS)-Sport Medicine Centre Voghera, University of Pavia","place":["Voghera, Italy"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Caio V.","family":"Spaggiari","sequence":"additional","affiliation":[{"name":"Cardiac Pacing Unit of the Heart Institute (InCor), Hospital das Cl\u00ednicas, Faculty of Medicine, University of S\u00e3o Paulo (HCFMUSP)","place":["S\u00e3o Paulo, Brazil"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Anna","family":"Odone","sequence":"additional","affiliation":[{"name":"Department of Public Health, Experimental and Forensic Medicine, University of Pavia","place":["Pavia, Italy"]},{"name":"Medical Direction, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Policlinico San Matteo","place":["Pavia, Italy"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Giuseppe","family":"D\u2019Antona","sequence":"additional","affiliation":[{"name":"Centtro di Ricerca Interdipartimentale Attivit\u00e0 Motorie e Sportive (CRIAMS)-Sport Medicine Centre Voghera, University of Pavia","place":["Voghera, Italy"]},{"name":"Department of Public Health, Experimental and Forensic Medicine, University of Pavia","place":["Pavia, Italy"]}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1965","published-online":{"date-parts":[[2026,5,1]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"1796","DOI":"10.1111\/sms.14007","article-title":"The importance of ventilatory thresholds to define aerobic exercise intensity in cardiac patients and healthy subjects","volume":"31","author":"Anselmi","year":"2021","journal-title":"Scand. 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