{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,10]],"date-time":"2026-09-10T22:25:08Z","timestamp":1789079108691,"version":"build-2803163510"},"reference-count":55,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,7,1]],"date-time":"2026-07-01T00:00:00Z","timestamp":1782864000000},"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>This research demonstrates how two distinct training modalities, high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT), influence oxygen transport dynamics and microvascular remodeling.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>\n                      Twenty-five healthy sedentary men and women (median age 21 years) were randomly assigned to HIIT or MICT for 8 weeks. VO\n                      <jats:sub>2max<\/jats:sub>\n                      improvement was assessed in all participants. Non-invasive maximal cardiac output measurements (Q\n                      <jats:sub>max<\/jats:sub>\n                      ) were performed in 15 participants. Biopsies from vastus lateralis were obtained, cleared and immunolabeled for VE-cadherin and alpha-smooth muscle actin, in 10 subjects, to observe microvasculature architecture. A computational hemodynamic model was constructed to estimate muscle flow dynamics.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      VO\n                      <jats:sub>2max<\/jats:sub>\n                      and Q\n                      <jats:sub>max<\/jats:sub>\n                      increased significantly in both training groups, with a greater improvement for VO\n                      <jats:sub>2max<\/jats:sub>\n                      in HIIT that was accompanied by a significant increase in capillaries pericyte coverage. No formation of new capillaries nor anastomoses (angiogenesis) was detected in either group. Modelisation estimated higher shear stress during HIIT than MICT and pericyte recruitment was modelized to adapt to shear stress level limiting excessive capillary dilation.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>\n                      HIIT induces superior improvements in VO\n                      <jats:sub>2max<\/jats:sub>\n                      and distinct microvascular structural adaptations rather than angiogenesis. HIIT is thought to induce protective capillary adaptation, limiting dilation during maximal effort and improving oxygen diffusion.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Clinical trial registration<\/jats:title>\n                    <jats:p>\n                      <jats:uri>https:\/\/clinicaltrials.gov\/study\/NCT07237854<\/jats:uri>\n                      , identifier NCT07237854.\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fphys.2026.1840439","type":"journal-article","created":{"date-parts":[[2026,7,1]],"date-time":"2026-07-01T15:52:39Z","timestamp":1782921159000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":1,"title":["Vascular remodeling enhances high-flow muscle oxygen delivery following aerobic exercise training"],"prefix":"10.3389","volume":"17","author":[{"given":"E.","family":"Maufroy","sequence":"first","affiliation":[{"name":"Research Unit in Rehabilitation Sciences, Faculty of Human Movement Sciences, Universit\u00e9 libre de Bruxelles (ULB)","place":["Brussels, Belgium"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"C.","family":"Rigaut","sequence":"additional","affiliation":[{"name":"Transferts, Interfaces and Processes, Ecole Polytechnique de Bruxelles, Universit\u00e9 libre de Bruxelles (ULB)","place":["Brussels, Belgium"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"C.","family":"Maufroy","sequence":"additional","affiliation":[{"name":"Research Unit in Rehabilitation Sciences, Faculty of Human Movement Sciences, Universit\u00e9 libre de Bruxelles (ULB)","place":["Brussels, Belgium"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"N.","family":"Baeyens","sequence":"additional","affiliation":[{"name":"Laboratoire de Physiologie et Pharmacologie, Faculty of Medicine, Universit\u00e9 libre de Bruxelles (ULB)","place":["Brussels, Belgium"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"G.","family":"Deboeck","sequence":"additional","affiliation":[{"name":"Research Unit in Rehabilitation Sciences, Faculty of Human Movement Sciences, Universit\u00e9 libre de Bruxelles (ULB)","place":["Brussels, Belgium"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,7,1]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"311","DOI":"10.1111\/micc.12279","article-title":"A microvascular wall shear rate function derived from In Vivo hemodynamic and geometric parameters in continuously branching arterioles","volume":"23","author":"Al-Khazraji","year":"2016","journal-title":"Microcirculation"},{"key":"B2","doi-asserted-by":"publisher","first-page":"279","DOI":"10.1007\/s40279-014-0272-9","article-title":"Exercise modalities and endothelial function: a systematic review and dose\u2013response meta-analysis of randomized controlled trials","volume":"45","author":"Ashor","year":"2015","journal-title":"Sports Med."},{"key":"B3","doi-asserted-by":"publisher","first-page":"1991","DOI":"10.1249\/mss.0000000000002993","article-title":"Change in central cardiovascular function in response to intense interval training: a systematic review and meta-analysis","volume":"54","author":"Astorino","year":"2022","journal-title":"Med. 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